Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 11/12/11
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
1030 AM PST SAT NOV 12 2011
.SYNOPSIS...
AN AREA OF LOW PRESSURE OFF THE SOUTHERN CALIFORNIA COAST WILL
CONTINUE TO MOVE SOUTH TOWARDS BAJA CALIFORNIA TODAY. WRAP AROUND
MOISTURE COMBINED WITH INCREASING INSTABILITY WILL CONTINUE TO BRING
SCATTERED SHOWERS SOUTH OF POINT CONCEPTION TODAY...WITH ISOLATED
THUNDERSTORMS OVER THE COASTAL WATERS. A WARMING AND DRYING TREND
WILL START ON MONDAY AND SHOULD REACH SEASONAL NORMALS AROUND
MIDWEEK.
&&
.SHORT TERM (TODAY-MON)...
CUTOFF LOW PRESSURE SYSTEM CURRENTLY CENTERED NEAR 31N/123W...WITH
INFRARED SATELLITE IMAGERY SHOWING AN AREA OF COOLING CLOUD TOPS ON
THE NORTHEAST QUADRANT OF THE LOW CENTER. SEVERAL LIGHTNING STRIKES
HAVE ALSO BEEN DETECTED WITH THIS AREA OF CONVECTION...ABOUT 130
MILES SOUTHWEST OF SAN NICHOLAS ISLAND. THE CUTOFF LOW CENTER IS
EXPECTED TO CONTINUE NUDGE GRADUALLY EASTWARD TOWARDS BAJA THROUGH
THIS EVENING...WITH SOME WRAP AROUND MOISTURE CONTINUING TO STREAM
INTO SOUTHERN CALIFORNIA.
MAIN FORECAST CONCERN TODAY WILL BE EXTENT OF SHOWER ACTIVITY ACROSS
LOS ANGELES AND VENTURA COUNTIES...AS WELL AS THE CONVECTIVE
POTENTIAL FOR THE COASTAL WATERS. LATEST 12Z NAM MODEL SHOWS A GOOD
SURGE OF UPPER LEVEL SOUTHERLY WINDS AT 500 MB THIS AFTERNOON...WITH
AN AREA OF GOOD VORTICITY ADVECTION POINTED TOWARDS LOS ANGELES
COUNTY AND THE ADJACENT COASTAL WATERS. THERE IS ALSO SOME COLD AIR
ADVECTION ALOFT TODAY ACROSS THESE AREAS...WITH 500 MB TEMPERATURES
DROPPING TO -22 DEGREES CELSIUS THIS AFTERNOON. THE COLD AIR
ADVECTION WILL BRING INCREASING INSTABILITY THIS AFTERNOON...WITH
THE NAM BRINGING A LARGE AREA OF NEGATIVE LIFTED INDICES INTO OUR
COASTAL WATERS THIS AFTERNOON. IN FACT...THERE IS A LIFTED INDEX
BULLSEYE OF -5 CENTERED JUST WEST OF CATALINA! LATEST RUC SOLUTION
ALSO SHOWS THE INCREASING INSTABILITY FOR THE COASTAL WATERS THIS
AFTERNOON. FOR THE ABOVE MENTIONED REASONS...AND BASED ON LATEST NAM
MOS GUIDANCE...HAVE BUMPED UP POPS A BIT FOR THIS AFTERNOON AND
EVENING ACROSS LOS ANGELES AND VENTURA COUNTIES...WITH GENERALLY
SCATTERED COVERAGE. ALSO INTRODUCED A SLIGHT CHANCE OF THUNDERSTORMS
ACROSS THE COASTAL WATERS FOR THIS AFTERNOON...INCLUDING CATALINA
ISLAND. HAVE ISSUED A MARINE WEATHER STATEMENT (LAXMWSLOX) TO
HIGHLIGHT THIS CONVECTIVE POTENTIAL FOR THE COASTAL WATERS...AND
ALSO MENTIONED THAT CONDITIONS ARE FAVORABLE FOR ISOLATED
WATERSPOUTS. SNOW LEVELS WILL GENERALLY RANGE BETWEEN 6000 AND 6500
FEET TODAY...WITH ONLY SMALL ACCUMULATIONS EXPECTED.
*** FROM PREVIOUS DISCUSSION ***
BY SUNDAY...THE UPPER LOW WILL BE WELL SOUTH COMING ASHORE ACROSS
CENTRAL BAJA. THIS WILL BRING HIGHER HEIGHTS AND THICKNESS LVLS
ACROSS THE REGION. TEMPS WILL REMAIN QUITE MILD WITH A FEW DEGREES
OF WARMING ON SUNDAY AND A FEW VALLEY AREAS REACHING THE LOWER 70S.
THERE WILL CONTINUE TO BE PARTLY CLOUDY SKIES DUE TO SOME LINGERING
LOW LEVEL MOISTURE BUT NO SHOWERS ARE EXPECTED. THERE WILL BE PATCHY
LOW CLOUDS AND FOG DEVELOPING ACROSS THE CENTRAL COAST AND LA/VTU
COASTAL AREAS BY LATE SUNDAY NIGHT INTO MONDAY. THERE WILL BE SOME
ADDITIONAL WARMING ON MONDAY WITH HIGHS STILL RANGING IN THE 60S TO
MID 70S. EXPECT MOSTLY SUNNY SKIES.
.LONG TERM (TUE-FRI)...BOTH GFS AND ECMWF ARE IN GENERALLY GOOD
AGREEMENT THROUGH THE LONG TERM FOR THE MOST PART. BROAD NW FLOW
ALOFT ON TUE WILL BECOME MORE ZONAL WED AND THU CONTINUING FAIR
WEATHER CONDITIONS. ANOTHER UPPER LOW WILL BEGIN TO DESCEND OUT OF
THE GULF OF ALASKA TOWARDS THE PAC NW. THIS WILL DEEPEN A TROUGH
OVER MUCH OF CALIFORNIA WITH A COOLING TREND LIKELY. THERE COULD BE
ANOTHER ROUND OF RAIN ON TAP FOR NEXT WEEKEND...BUT WAY TOO EARLY TO
INTRODUCE POPS.
&&
.AVIATION...12/1800Z.
MID/UPPER LEVEL LOW PRESSURE SYSTEM CENTERED APPROXIMATELY 270 MILES
SOUTHWEST OF KLAX WILL CONTINUE TO SHIFT SOUTHEAST. MODERATE UPPER
LEVEL SOUTHWEST WINDS WILL BECOME STRONG NORTHEAST AND LIGHT MID
LEVEL SOUTH WINDS BECOME LIGHT EAST AFTER 13/05Z. ISOLATED
THUNDERSTORMS OVER THE OUTER WATERS WILL MOVE NORTHEAST AT 30KT WITH
TOPS APPROXIMATELY 30KFT BETWEEN 12/20-12/23Z THEN MOVE NORTH AT
10KT BETWEEN 12/23-13/01Z . FREEZING LEVEL WAS APPROXIMATELY 8KFT
AND WILL DIFFER BY PLUS 1KFT BY 13/18Z.
KLAX...CIGS 035 LIKELY THROUGH 13/03Z WITH -SHRA. CHANCE BKN060
BETWEEN 13/03-13/06Z.
KBUR...CIGS 035 LIKELY THROUGH 12/21Z...THEN BKN050 AND -SHRA
THROUGH 13/03Z.
VIRTUALLY CERTAIN - 95-100%
VERY LIKELY - 80-95%
LIKELY - 60-80%
CHANCE - 30-60%
VERY UNLIKELY - 20% OR LESS
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).
&&
$$
PUBLIC...GOMBERG/KAPLAN
SYNOPSIS...GOMBERG
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
348 PM PST FRI NOV 11 2011
.DISCUSSION...AS OF 1:40 PM PST VETERANS DAY...RADAR AND SFC OBS
ARE INDC PLENTY OF SHOWERS ACROSS THE DISTRICT...MAINLY SOUTH OF
THE SAN JOSE AREA. SATL IMAGERY IS STILL SHOWING THE FRONT
OFFSHORE...WITH THE BUOYS AND SFC OBS STILL SHOWING A SE WIND.
THERE HAS BEEN SOME ENHANCEMENT OF THE FRONT WITH COOLING CLOUD
TOPS DUE TO A JET STREAK. THE MAIN UPPER LOW IS MOVING ESE...AND
IS CURRENTLY NEAR 33.5/128.5. MOST OF THE 12Z MODELS HAD A POOR
HANDLE ON THE UPPER LOW AND THE EXTENT OF THE SHOWER
ACTIVITY...WITH THE HRRR AND THE ECMWF HAVING THE BEST HANDLE.
SOME LOCATIONS IN MONTEREY COUNTY HAD MORE THAN 0.50 INCHES OF
RAIN TODAY. IN THE SF BAY AREA RAINFALL TOTALS WERE GENERALLY LESS
THAN 0.10 INCHES.
THE UPPER LOW WILL CONTINUE TO MOVE TO THE SE TONIGHT AND SATURDAY.
THERE WILL BE A CHANCE OF SHOWERS THIS EVENING...WITH LIKELY POPS
IN THE SOUTH. SHOWERS WILL END FROM THE NORTH AFTER MIDNIGHT.
THERE COULD BE A FEW LEFT OVER SHOWERS SAT MORNING IN THE SOUTHERN
PORTIONS OF THE DISTRICT...BUT WITH HIGH PRESSURE BUILDING IN FROM
THE PACIFIC SHOWERS WILL END BY MID MORNING.
HIGH PRESSURE OVER THE EASTERN PACIFIC WILL RESULT IN A DRY NW
FLOW OVER THE DISTRICT. TEMPS WILL BE NEAR NORMAL WITH MOSTLY
CLEAR SKIES FROM SUNDAY THOUGH WEDNESDAY NIGHT.
TOWARDS THE END OF THE WEEK THE PATTERN WILL CHANGE ONCE AGAIN AS
BOTH THE GFS AND ECMWF BEGIN TO DEEPEN A LONG WAVE TROF OVER THE
WEST COAST AS A DEEP UPPER LOW MOVES SE FROM SOUTHERN ALASKA. IT
LOOKS LIKE THIS DEEPENING TROF AND ASSOCIATED COLD FRONT WILL
BRING AN INCREASING CHANCE OF SHOWERS TO THE DISTRICT STARTING IN
THE NORTH BAY ON THURSDAY WITH SHOWERS POSSIBLE FURTHER SOUTH
THURSDAY NIGHT. THE PATTERN LOOKS UNSETTLED THROUGH NEXT WEEKEND
WITH SHOWERS POSSIBLE. THE GFS ALSO DROPS MUCH COLDER AIR OVER THE
DISTRICT...WITH 850 MB TEMPS BELOW ZERO NEXT WEEKEND...AS LOW AS
-4C IN THE NORTH BAY.
&&
.AVIATION...AS OF 3:45 PM PST FRIDAY...BAND OF RAIN SEEN ON KMUX
RADAR IS BEGINNING TO MOVE ONSHORE ACROSS THE SAN FRANCISCO
PENINSULA. NORTHERN MONTEREY COUNTY WILL ALSO BE IMPACTED SOON.
LOCALLY WINDS ARE GUSTY FROM THE SE FOR EXAMPLE KSNS REPORTS GUSTS
TO 32 KNOTS AT THE MOMENT. ELSEWHERE ON AVERAGE WINDS ARE MUCH
LIGHTER AND THE TREND TONIGHT IS FOR THEM TO DECREASE.
VICINITY OF KSFO...MVFR TO VFR CONDITIONS WILL PREVAIL TONIGHT.
MORE RAIN IS ON THE DOORSTEP. SURFACE WINDS WILL TREND TO WESTERLY
ON SATURDAY. BY SATURDAY AFTERNOON WEST WINDS TO 15 KNOTS ARE FORECAST.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MORE STEADY RAINS ARRIVING SOON.
GENERALLY VFR CONDITIONS BUT LOCAL MVFR IS POSSIBLE IN HEAVIER
SHOWERS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...ROUGH BAR ADVISORY FOR SF BAR UNTIL 6 PM
&&
$$
PUBLIC FORECAST: STROBIN
AVIATION/MARINE: CANEPA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
152 PM PST FRI NOV 11 2011
.DISCUSSION...AS OF 1:40 PM PST VETERANS DAY...RADAR AND SFC OBS
ARE INDC PLENTY OF SHOWERS ACROSS THE DISTRICT...MAINLY SOUTH OF
THE SAN JOSE AREA. SATL IMAGERY IS STILL SHOWING THE FRONT
OFFSHORE...WITH THE BUOYS AND SFC OBS STILL SHOWING A SE WIND.
THERE HAS BEEN SOME ENHANCEMENT OF THE FRONT WITH COOLING CLOUD
TOPS DUE TO A JET STREAK. THE MAIN UPPER LOW IS MOVING ESE...AND
IS CURRENTLY NEAR 33.5/128.5. MOST OF THE 12Z MODELS HAD A POOR
HANDLE ON THE UPPER LOW AND THE EXTENT OF THE SHOWER
ACTIVITY...WITH THE HRRR AND THE ECMWF HAVING THE BEST HANDLE.
SOME LOCATIONS IN MONTEREY COUNTY HAD MORE THAN 0.50 INCHES OF
RAIN TODAY. IN THE SF BAY AREA RAINFALL TOTALS WERE GENERALLY LESS
THAN 0.10 INCHES.
THE UPPER LOW WILL CONTINUE TO MOVE TO THE SE TONIGHT AND SATURDAY.
THERE WILL BE A CHANCE OF SHOWERS THIS EVENING...WITH LIKELY POPS
IN THE SOUTH. SHOWERS WILL END FROM THE NORTH AFTER MIDNIGHT.
THERE COULD BE A FEW LEFT OVER SHOWERS SAT MORNING IN THE SOUTHERN
PORTIONS OF THE DISTRICT...BUT WITH HIGH PRESSURE BUILDING IN FROM
THE PACIFIC SHOWERS WILL END BY MID MORNING.
HIGH PRESSURE OVER THE EASTERN PACIFIC WILL RESULT IN A DRY NW
FLOW OVER THE DISTRICT. TEMPS WILL BE NEAR NORMAL WITH MOSTLY
CLEAR SKIES FROM SUNDAY THOUGH WEDNESDAY NIGHT.
TOWARDS THE END OF THE WEEK THE PATTERN WILL CHANGE ONCE AGAIN AS
BOTH THE GFS AND ECMWF BEGIN TO DEEPEN A LONG WAVE TROF OVER THE
WEST COAST AS A DEEP UPPER LOW MOVES SE FROM SOUTHERN ALASKA. IT
LOOKS LIKE THIS DEEPENING TROF AND ASSOCIATED COLD FRONT WILL
BRING AN INCREASING CHANCE OF SHOWERS TO THE DISTRICT STARTING IN
THE NORTH BAY ON THURSDAY WITH SHOWERS POSSIBLE FURTHER SOUTH
THURSDAY NIGHT. THE PATTERN LOOKS UNSETTLED THROUGH NEXT WEEKEND
WITH SHOWERS POSSIBLE. THE GFS ALSO DROPS MUCH COLDER AIR OVER THE
DISTRICT...WITH 850 MB TEMPS BELOW ZERO NEXT WEEKEND...AS LOW AS
-4C IN THE NORTH BAY.
&&
.AVIATION...AS OF 9:45 AM PST FRIDAY...DIFFICULT FORECAST OVER THE
NEXT 6 HOURS...AS NONE OF THE SHORT TERM MODELS ARE HANDLING THE
CURRENT SURFACE LOW PROPERLY. LIGHT TO MODERATE RAIN EXTENDS FROM
KSTS...SOUTH THROUGH KMRY...WITH MODERATE SOUTHEAST WINDS AND
OCCASIONAL MVFR VIS. CIGS CONTINUE TO DROP ACROSS THE
REGION...WITH MVFR POSSIBLE THROUGH MANY OF THE TERMINALS OVER THE
NEXT FEW HOURS. STEADY RAIN SHOULD BECOMING MORE SHOWERY IN
ACTIVITY BY 21Z...WITH AN INCREASE IN CIGS AND WEAKER WINDS AS THE
COLD FRONT MOVES EAST. THE NAM HINTS AT MVFR TO IFR CIGS EARLY
SATURDAY MORNING...LOW CONFIDENCE.
VICINITY OF KSFO...MAINLY VFR CONDITIONS WILL PREVAIL...EXCEPT
OVER THE NEXT 2 HOURS...WHERE MVFR CIGS AND VIS WILL BE POSSIBLE.
GUSTY SOUTHEAST WINDS WILL BE PRESENT AT THE TERMINALS AHEAD OF A
COLD FRONT...CURRENTLY OFFSHORE. THESE WINDS WILL VEER AND WEAKEN LATE THIS
MORNING INTO THE AFTERNOON HOURS. OTHERWISE...MVFR CIGS WILL BE
POSSIBLE OVERNIGHT INTO THE EARLY MORNING HOURS ON SATURDAY...LOW
CONFIDENCE.
KSFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...LIGHT TO MODERATE RAIN WILL CONTINUE
THROUGH THE EARLY AFTERNOON HOURS...POSSIBLY EXTENDING INTO THE
EVENING HOURS. STRONG SOUTHEAST WINDS AT KSNS WILL CONTINUE INTO
THE AFTERNOON HOURS...BEFORE SUBSIDING. A FEW OF THE SHORT TERM
MODELS INDICATE THAT THE MONTEREY BAY TERMINALS WILL SEE THE MOST
RAIN ACTIVITY TODAY...SO AT LEAST LIGHT SHOWERS WERE KEPT IN THE
FORECAST OVER THE NEXT 24 HOURS.
&&
.MARINE/BEACH...AS OF 3:45 AM PST FRIDAY...THE PERSISTENT LOW PRESSURE
SYSTEM POSITIONED APPROX 450 NM OFFSHORE HAS PRODUCED A LONG
PERIOD WESTERLY SWELL. THE SWELL IS BETWEEN 8 AND 10 FEET WITH A
DOMINANT PERIOD OF 15 SECONDS. ALTHOUGH...THIS SWELL WILL PRODUCE
SUB HIGH SURF ADVISORY CONDITIONS THOSE VENTURING INTO THE WATER
ALONG CENTRAL COAST BEACHES SHOULD BE AWARE OF A HEIGHTENED RISK
OF RIP CURRENTS AS A RESULT OF THIS LONGER PERIOD WESTERLY SWELL.
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...SF BAY UNTIL 9 PM
SCA...MRY BAY UNTIL 9 PM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 9 PM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 9 PM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 9 PM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 9 PM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM UNTIL 1 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 1 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR UNTIL 4 PM
&&
$$
PUBLIC FORECAST: STROBIN
AVIATION/MARINE: RILEY
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
252 PM MST SAT NOV 12 2011
.SHORT TERM /TONIGHT THROUGH MONDAY/...
AT 2 PM THE SURFACE FRONT WAS THROUGH SLC AND APPROACHING PROVO AND
VERNAL...WITH SNOW FALLING AT HILL AFB AND EVANSTON WY...SO IT IS
RIGHT ON TRACK ACCORDING TO MODEL TIMING. ALSO AS PROJECTED THE
ACTIVE AREA OF THE FRONT IS DIMINISHING IN SIZE AND THE FRONTAL ZONE
IS GROWING THINNER IN SATELLITE IMAGERY AND RUC ANALYSIS. THE PERIOD
OF MAXIMUM ACTIVE WEATHER IN NE UT AND NW CO WILL BE RELATIVELY BRIEF
TONIGHT. PRIME TIME FOR BEST SNOWFALL AND STRONGEST WINDS SHOULD BE
BETWEEN 9 PM AND MIDNIGHT. HAVE INCREASED THE CHC OF PRECIP OVER THE
NORTHERN 2/3RDS OF THE AREA...VALLEYS AND MOUNTAINS...FOR THIS
EVENING AND OVERNIGHT...HAVING HIGHER CERTAINTY WITH THIS INITIAL
SPURT OF RAIN AND SNOW. THE SNOWFALL IN THE MOUNTAINS SHOULD BE
ENOUGH FOR SEVERAL INCHES TO ACCUMULATE...ALONG WITH STRONG WESTERLY
FLOW AT AND JUST BELOW MOUNTAINTOP LEVEL. THIS SHOULD BE ENOUGH FOR
THE BLIZZARD CONDITIONS TO MATERIALIZE. STILL EXPECT RABBIT EARS AND
VAIL PASSES TO SEE G50-60MPH THIS EVENING...WITH DRIFTING AND
WHITEOUT CONDITIONS MAKING TRAVEL DANGEROUS IF NOT IMPOSSIBLE.
AFTER THIS FRONT PASSES THERE WILL BE A LULL IN THE WINTER WEATHER
BETWEEN 06Z AND 12Z TONIGHT. THIS WILL BE FOLLOWED BY A SECOND SURGE
SUNDAY. THIS WEAKER FRONT WILL BRING COOLER AIR THAT WILL RUN INTO
SLIGHTLY WARMER AIR IN PLACE OVER THE AREA. SOME OVERRUNNING IS
POSSIBLE RESULTING IN WIDESPREAD SNOWFALL OVER NW AND CENTRAL CO...
INCLUDING THE LOWER ELEVATIONS.
COLDER CONDITIONS AND RAPID CLEARING WILL FOLLOW THE SECOND SYSTEM
SUNDAY NIGHT AND MONDAY.
THANKS TO BOU PUB AND ABQ FOR COORDINATION.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
SHORT-WAVE TRAIN FROM THE ALEUTIANS INTO THE NORTHERN PLAINS BEHIND
THIS STORM SYSTEM AND RE-ENFORCE THE NORTHWEST FLOW OVER THE
NORTHERN ROCKIES LATE MONDAY NIGHT INTO TUESDAY. 295K THETA SURFACE
NOT SHOWING A LARGE AMOUNT OF MOISTURE MOVING IN FROM THE
PACIFIC...BUT IT IS TAKING A FAVORABLE ROUTE AND NOT BEING SQUEEZED
OUT BY ANY BIG RANGES BEFORE HITTING THE NORTHERN COLORADO
MOUNTAINS. THE LARGE SCALE ASCENT INCREASES AFTER MIDNIGHT ON MONDAY
WHEN JET SUPPORT ARRIVES ALONG WITH THE STRONGEST OF THE EMBEDDED
WAVES. OROGRAPHICS SHOULD CONTINUE TO FAVOR THE WESTERN ASPECTS FROM
STEAMBOAT DOWN TO CRESTED BUTTE...AND HAVE NUDGED POPS UP SLIGHTLY
WITH ONLY A FEW INCHES OF ACCUMULATION STILL INDICATED.
THE UPPER FLOW PATTERN WILL BEGIN TO DE-AMPLIFY DURING THE MID WEEK
TIME FRAME BUT A BUILDING RIDGE INTO THE NORTHEAST PACIFIC/GULF OF
ALASKA REGION...WILL ALLOW FOR ANOTHER TROF TO BEGIN TO CARVE OUT
ACROSS THE NORTHWEST STATES BY LATE IN THE WEEK. THE TREND THE
WESTERN TROF FORMATION HAS BEEN SLOWED DOWN FROM PREVIOUS RUNS AND
THIS SHOULD KEEP MAINLY DRY CONDITIONS IN PLACE THROUGH LATE WEEK.
WITH THE STRONGER WESTERLY...THEN SOUTHWESTERLY FLOW IN PLACE A
REBOUND IN TEMPERATURES SHOULD OCCUR AND TEMPERATURES SHOULD RISE TO
AT LEAST SEASONAL LEVELS BY MID WEEK AND POSSIBLY ABOVE IN AN
INCREASING WARM AIR ADVECTION PATTERN. THERE ARE SOME TIMING
DIFFERENCES BY THE FIRST HALF OF NEXT WEEKEND WHEN THE FIRST LEADING
ENERGY EJECTS FROM THE TROF INTO THE EASTERN GREAT BASIN AND
THEREFORE PRECIPITATION CHANCES WILL REMAIN ON THE LOW SIDE.
&&
.AVIATION /FOR 00Z TAF ISSUANCE/...
VFR CONDITIONS CONTINUE TO PREVAIL AT FLIGHT TERMINAL SITES THIS
AFTERNOON AS MOISTURE CONTINUES TO STREAM INTO THE REGION AHEAD OF A
COLD STILL JUST OUTSIDE OUR NORTHEAST CWA. SOME PASSING SHOWERS HAVE
DROPPED CONDITIONS TO THE MVFR CATEGORY AT THE HIGH VALLEY AND
MOUNTAIN SITES. THIS TREND SHOULD INCREASE THROUGH THE EVENING AS
BROAD SCALE LIFT WORKS ON THIS MOISTURE AND FRONTAL PASSAGE INTO THE
NORTHERN CWA PROVIDE LOW LEVEL FOCUS. LOCAL IFR/LIFR CONDITIONS
EAST OF A LINE FROM KCAG TO KRIL TO KASE THE EVENING CAN BE EXPECTED
AS WELL AS STRONG WINDS AHEAD AND ALONG THE FRONT. THESE WINDS
WILL COMBINE WITH INCREASING SNOWFALL TO DROP VISIBILITIES WELL
UNDER A MILE AT TIMES. WINDS GUSTING 30-50KTS IN THIS AREA WILL ALSO
CREATE HAZARDOUS CONDITIONS TO LIGHT AIRCRAFT. THE HIGHER TERMINAL
SITES WILL MOST LIKELY SEE IFR/LIFR CONDITIONS THROUGH THE NIGHT IN
LIGHT TO MODERATE SNOW WITH THE MOUNTAINS AND HIGHER PASSES OBSCURED
BY LOW CLOUDS AND PRECIPITATION. LOWER ELEVATIONS TAF SITES SUCH AS
KGJT...KMTJ...KVEL WILL SLOWLY DEGRADE TOWARD SUNRISE ON SUNDAY WHEN
A SECONDARY SYSTEM PUSHES THROUGH WITH ADDITIONAL MOISTURE.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM MST
SUNDAY FOR ZONES 002-003-008-009-018-019.
WINTER STORM WARNING UNTIL MIDNIGHT MST SUNDAY NIGHT FOR ZONES
010-012.
BLIZZARD WARNING UNTIL MIDNIGHT MST SUNDAY NIGHT FOR ZONES 004-
013.
WINTER WEATHER ADVISORY UNTIL TO 6 PM MST SUNDAY FOR ZONE 005.
UT...NONE.
&&
$$
SHORT TERM...CJC
LONG TERM....15
AVIATION.....TGJT
AREA FORECAST DISCUSSION
NWS DENVER CO
1139 AM MST SAT NOV 12 2011
.UPDATE...HAVE BEEN GETTING WIND GUST REPORTS OF 65 TO 80 MPH THIS
MORNING OVER THE FOOTHILLS...EXPECT THIS TO CONTINUE THROUGH THE
DAY AND EVENING. HAVE UPDATED THE HIGH WIND WARNING TO EXTEND THE
FOOTHILLS WARNING UNTIL TOMORROW MORNING AND THE WESTERN URBAN
CORRIDOR UNTIL MIDNIGHT. MODEL CROSS SECTIONS ARE SHOWING STRONGER
WINDS COMING LATER THIS EVENING INTO THE NIGHT AS THE COLD FRONT
NEARS THEN ALSO AS THE UPPER DISTURBANCE PASSES AND STRONG
SUBSIDENCE WILL PUSH THE STRONGER WINDS DOWN TO THE SURFACE. LOOKS
LIKE THE NORTHERN BORDER AREA OUT TO THE KANSAS BORDER AS WELL
WILL SEE WINDS GUSTING TO ABOUT 50 MPH AFTER MIDNIGHT AS THE UPPER
TROUGH PASSES. DO NOT BELIEVE THEY WILL NEED A HIGHLIGHT AT THIS
TIME. WINTER HIGHLIGHTS LOOK ON TRACK AS WEBCAMS OVER THE HIGH
COUNTRY SHOW VISIBILITIES BEING REDUCED AND ROADS BECOMING SNOW
PACKED. SNOW RATES WILL BE INCREASING THROUGH THE AFTERNOON WITH
HEAVIEST RATES STILL EXPECTED THIS EVENING.
&&
.AVIATION...WINDS PROVING TO BE DIFFICULT AS MOUNTAIN WAVE MAKES
WINDS GUSTY ON AND OFF...BUT STILL EXPECTING MAINLY WEST WINDS AS
SURFACE TROUGH REMAINS OVER THE EAST PLAINS. THE STRONGEST WINDS
STILL EXPECTED AROUND 20-03Z. A COLD FRONT WILL PUSH THROUGH THE
AREA THIS EVENING CAUSING WINDS TO SHIFT NORTHWEST. AFTER
07Z...WINDS WILL BECOME EASTERLY AS A SURFACE HIGH MOVES IN BEHIND THE
FRONT...BEFORE BECOMING MORE SOUTHEASTERLY THROUGH THE NIGHT.
AIRPORTS WILL RETURN TO A WEST WIND TOMORROW MORNING...WITH KBJC
EXPECTED TO RETURN TO WEST SOONER. WIND SPEEDS TOMORROW SHOULD BE
LIGHTER THAN TODAY. ONLY EXPECT MID AND HIGH CLOUDS THROUGH
TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 353 AM MST SAT NOV 12 2011/
SHORT TERM...WATER VAPOR SATELLITE IMAGERY SHOWING A TIGHTLY WOUND
UPPER LEVEL TROUGH OVER EASTERN WASHINGTON AT THIS TIME. THIS TROUGH
WILL MOVE INTO WYOMING THIS AFTERNOON AND THEN ACROSS NEBRASKA
TONIGHT. VERY WINDY CONDITIONS STILL EXPECTED FOR THE MOUNTAINS AND
FRONT RANGE TODAY. A MOUNTAIN WAVE IS STARTING TO SET UP WILL BE IN
PLACE THROUGH LATE MORNING. WINDS ARE STARTING TO PICK UP WITH GUSTS
OF 40-60 MPH IN PART OF THE MOUNTAINS AND FOOTHILLS. MODELS INDICATE
THE STRONGEST WINDS ASSOCIATED WITH THE MOUNTAIN WAVE WILL OCCUR
BETWEEN 12Z AND 18Z. THE HRRR AND RUC13 ARE SHOWING SURFACE WINDS
SUSTAINED UP TO 50 KNOTS IN PARTS OF THE FOOTHILLS. BIGGEST QUESTION
WILL BE HOW FAR EAST THESE STRONG WINDS WILL SPREAD. MOUNTAIN WAVE
WILL DISSIPATE THIS AFTERNOON HOWEVER...STRONG WINDS WILL REMAIN
POSSIBLE AS DAYTIME MIXING WILL HELP WINDS ALOFT SURFACE. THE NAM12
SHOWS 700MB WINDS REACHING 40-70 KNOTS THIS AFTERNOON SO HIGH WINDS
WILL REMAIN POSSIBLE. THE THREAT FOR HIGH WINDS WILL END THIS
EVENING AS A COLD FRONT PUSHES ACROSS THE AREA. IT WILL REMAIN WINDY
BEHIND THE FRONT FOR A FEW HOURS BUT THE STRONG WINDS ALOFT WILL BE
UNABLE TO MIX TO THE SURFACE BECAUSE THE AIRMASS WILL DECOUPLE ALONG
THE FRONT RANGE.
ANOTHER BIG CONCERN WILL BE THE SNOW AND BLOWING SNOW IN THE
MOUNTAINS. AIRMASS IS QUITE DRY OVER THE NORTH CENTRAL MOUNTAINS
RIGHT NOW SO IT WILL TAKE A WHILE TO MOISTEN IT UP. MAY SEE A FEW
LIGHT SNOW SHOWERS THIS MORNING...BUT MOST LOCATIONS WILL HAVE TO
WAIT UNTIL THIS AFTERNOON FOR THE SNOW TO BEGIN. STRONG WINDS ALOFT
COMBINED WITH INCREASING MOISTURE WILL PRODUCE OROGRAPHIC SNOW.
EXPECT TO SEE A PERIOD OF MODERATE TO HEAVY SNOW THIS EVENING WHEN A
FEW FACTORS COME TOGETHER. COLD FRONT WILL PUSH ACROSS THE MOUNTAINS
EARLY THIS EVENING CAUSING WINDS TO TURN A MORE FAVORABLE NORTHWEST
DIRECTION. COLD AIR ADVECTION BEHIND THE FRONT WILL INCREASE LAPSE
RATES. THESE COMBINED WITH INCREASING MOISTURE SHOULD CREATE A
PERIOD OF WIDESPREAD MODERATE TO HEAVY SNOW. MODELS THEN SHOW RAPID
DRYING AFTER MIDNIGHT AND BY SUNDAY MORNING SNOW WILL HAVE STOPPED
MOST PLACES. WILL KEEP THE WARNINGS IN EFFECT THROUGH SUNDAY THOUGH
AS ANOTHER SURGE OF MOISTURE MOVE OVER THE MOUNTAINS AND PRODUCES
MORE SNOW ON SUNDAY.
WINTER STORM WARNINGS ARE CURRENTLY IN EFFECT FOR THE MOUNTAINS AND
ADVISORIES FOR THE VALLEYS. SNOWFALL AMOUNTS FOR THE NEXT 24 HOURS
ARE LOOKING LIKE 6-12" FOR ZONE 31...4-8 ZONE 33 AND 2-6" FOR ZONE
34. MAIN CONCERN WILL BE BLOWING AND DRIFTING SNOW DUE TO THE STRONG
WINDS. NOT CONFIDENT ENOUGH WIDESPREAD BLIZZARD CONDITIONS WILL
OCCUR TO UPGRADE TO A BLIZZARD WARNING. EXPECT SOME WIDESPREAD HARSH
CONDITIONS FOR A COUPLE HOURS BEHIND THE FRONT WITH THE MODERATE
SNOW...BUT THE SNOW WILL QUICKLY TAPER OFF. EXPOSED RIDGES SHOULD
SEE BLIZZARD CONDITIONS FOR MUCH OF THE NIGHT DUE TO VERY STRONG
WINDS ALOFT. MODELS WANT TO KEEP THE STRONG WINDS UP HIGH JUST OVER
THE RIDGES AFTER MIDNIGHT...THUS ANOTHER REASON TO NOT UPGRADE TO A
BLIZZARD WARNING AT THIS TIME.
TEMPERATURES ARE MILD NOW DUE TO THE DOWNSLOPE WINDS AND WILL REMAIN
MILD TODAY WITH HIGHS IN THE 60S FOR MOST OF NORTHEAST COLORADO. THE
FIRE DANGER WILL BE HIGH TODAY DUE TO THE STRONG WINDS. RELATIVE
HUMIDITIES ARE LOW RIGHT NOW WITH READINGS RUNNING IN THE 10-20%
RANGE. MODELS INDICATE THAT THE AIRMASS WILL MOISTEN THROUGH THE DAY
AND PUSH HUMIDITIES ABOVE 15%. THEREFORE WILL NOT ISSUE ANY RED FLAG
WARNING. IF THE DRY AIRMASS IS SLOW TO MOVE OUT A RED FLAG WARNING
WILL BE NEED FOR THE PLAINS.
LONG TERM...THE WEATHER ROLLER COASTER CONTINUES SUNDAY WITH
ANOTHER BOUT OF SNOW AND STRONG W-NWLY WINDS FOR THE HIGH COUNTY AND
GUSTY AND ERRATIC CHINOOK WINDS FOR THE FRONT RANGE AND NEARBY
PLAINS. BROAD UPPER TROUGH WITHIN THE NRN STREAM OF VERY STRONG
W/NWLY FLOW ALOFT IS TETHERED TO A CLOSED LOW AT MID-LEVELS OFF THE
NRN BAJA COAST. THE UPR TROUGH PASSES OVER COLORADO DURING THE DAY
SUNDAY. MODEL CROSS SECTIONS SHOW A DEEP LAYER OF MARGINALLY
UNSTABLE SATURATED AIR FROM THE CONTINENTAL DIVIDE WESTWARD DURING
THE MORNING AND EARLY AFTERNOON HOURS. BY LATE IN THE DAY THE DEPTH
OF THE MOIST LAYER BEGINS TO DECREASE WITH INCREASING SUBSIDENCE AND
STABILITY ON THE BACK SIDE OF THE EXITING UPPER TROUGH. 750-500 MB
WINDS PREDOMINANTLY WESTERLY IN DIRECTION THROUGH THE DAY SUNDAY
WITH SPEEDS AT 700MB ON THE ORDER OF 40-45KTS....AND UP AROUND 80
KTS ABOVE TIMBERLINE SUNDAY MORNING. AFTER 18Z/SUN MODEL WIND SPDS
DECREASE BUT REMAIN ZONAL...ONLY TO INCREASE AGAIN SUNDAY NIGHT WITH
STRONG MID-UPPER LEVEL SUBSIDENCE OVER THE FRONT RANGE. OVERNIGHT
THE I-25 URBAN CORRIDOR COULD SEE STG AND GUSTY COLD BORA TYPE
DOWNSLOPE WINDS DEVELOPING WITH COLD AIR ADVECTION KICKING IN WITH
PASSAGE OF A WEAK SECONDARY TROUGH AXIS. PERIOD OF STRONGEST WINDS
OVER AND ALONG THE FRONT RANGE APPEARS TO BE FROM 06Z/MON TO
18Z/MON. AT THIS TIME...SPEEDS DO NOT APPEAR TO REACH HIGH WIND
CRITERIA...BUT WOULDN/T BE SURPRISED IF WE HEAR OF A FEW WIND PRONE
AREAS HITTING IT TOWARDS MORNING. ON MONDAY AIRMASS DRIES OUT WITH
MODERATE NWLY FLOW ALOFT. MOISTURE BANKED UP AGAINST THE MTNS WEST
OF THE CONT DIVIDE COULD KEEP SNOW SHOWERS GOING FOR A GOOD PART OF
THE DAY...BUT RESULTING IN LITTLE IF ANY ADDITIONAL ACCUMULATION.
DOWNSLOPE FLOW OFF THE FRONT RANGE ON MONDAY IS EXPECTED TO KEEP
DAYTIME TEMPS ON THE MILD SIDE WITH HIGHS IN THE LOWER/MID 50S ON
THE PLAINS. THAT/S ABOUT AVERAGE FOR THE DATE. SHOULD ALSO SEE
PLENTY OF SUNSHINE EAST OF THE MTNS THAT DAY.
LOOKING AHEAD...MODELS SHOW YET ANOTHER BATCH OF PACIFIC MOISTURE
RACING SEWRD ACROSS THE REGION ON TUESDAY. THE NORTHERN MTNS COULD
SEE A RESURGENCE IN SNOW SHOWER ACTIVITY DURING THE DAY...BUT ANY
ACCUMULATION SHOULD BE MINOR AND MAINLY CONFINED TO NORTHWEST SLOPES
NORTH OF I-70. OTHERWISE SHOULD SEE MORE MID-LEVEL CLOUD COVER EAST
OF THE MTNS ON TUESDAY...AND WITH COOLING ALOFT SHOULD SEE THE
COOLEST TEMPERATURES OF THE WEEK ON TUESDAY. STILL ABOUT AVERAGE FOR
THE DATE. MODELS SHOWS DRYING OVERNIGHT AND WINDS EASING AS THE JET
STREAM SHIFTS NORTHWARD WITH A BROAD ZONAL FLOW PATTERN SETTING UP
OVER THE WESTERN CONUS. REST OF THE WEEK LOOKS DRY WITH PERIODS OF
GUSTY WINDS AND SLIGHTLY ABOVE AVERAGE TEMPERATURES THE RULE.
AVIATION...A SURFACE TROUGH OVER THE EASTERN PLAINS OF COLORADO
WILL KEEP WINDS WEST TO SOUTHWEST THROUGH THE DAY TODAY. WINDS WILL
BECOME GUSTY DUE TO STRONG WINDS ALOFT. THE STRONGEST WINDS AT KDEN
AND KAPA WILL BE 20-03Z. A COLD FRONT WILL PUSH THROUGH THE AREA
THIS EVENING CAUSING WINDS TO SHIFT NORTHWEST. AFTER 06Z...WINDS
WILL BECOME EASTERLY AS A SURFACE MOVES IN BEHIND THE FRONT. ONLY
EXPECT MID AND HIGH CLOUDS THROUGH TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FOR THE FRONT RANGE FOOTHILLS UNTIL 6 AM MST
SUNDAY FOR COZ035-036.
HIGH WIND WARNING FOR THE WESTERN URBAN CORRIDOR UNTIL MIDNIGHT
MST TONIGHT FOR COZ038-039.
WINTER STORM WARNING UNTIL MIDNIGHT MST SUNDAY NIGHT FOR COZ031-
033-034.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 5 PM MST
SUNDAY FOR COZ030-032.
&&
$$
SHORT TERM...MEIER
LONG TERM....BAKER
UPDATE/AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS DENVER CO
353 AM MST SAT NOV 12 2011
.SHORT TERM...WATER VAPOR SATELLITE IMAGERY SHOWING A TIGHTLY WOUND
UPPER LEVEL TROUGH OVER EASTERN WASHINGTON AT THIS TIME. THIS TROUGH
WILL MOVE INTO WYOMING THIS AFTERNOON AND THEN ACROSS NEBRASKA
TONIGHT. VERY WINDY CONDITIONS STILL EXPECTED FOR THE MOUNTAINS AND
FRONT RANGE TODAY. A MOUNTAIN WAVE IS STARTING TO SET UP WILL BE IN
PLACE THROUGH LATE MORNING. WINDS ARE STARTING TO PICK UP WITH GUSTS
OF 40-60 MPH IN PART OF THE MOUNTAINS AND FOOTHILLS. MODELS INDICATE
THE STRONGEST WINDS ASSOCIATED WITH THE MOUNTAIN WAVE WILL OCCUR
BETWEEN 12Z AND 18Z. THE HRRR AND RUC13 ARE SHOWING SURFACE WINDS
SUSTAINED UP TO 50 KNOTS IN PARTS OF THE FOOTHILLS. BIGGEST QUESTION
WILL BE HOW FAR EAST THESE STRONG WINDS WILL SPREAD. MOUNTAIN WAVE
WILL DISSIPATE THIS AFTERNOON HOWEVER...STRONG WINDS WILL REMAIN
POSSIBLE AS DAYTIME MIXING WILL HELP WINDS ALOFT SURFACE. THE NAM12
SHOWS 700MB WINDS REACHING 40-70 KNOTS THIS AFTERNOON SO HIGH WINDS
WILL REMAIN POSSIBLE. THE THREAT FOR HIGH WINDS WILL END THIS
EVENING AS A COLD FRONT PUSHES ACROSS THE AREA. IT WILL REMAIN WINDY
BEHIND THE FRONT FOR A FEW HOURS BUT THE STRONG WINDS ALOFT WILL BE
UNABLE TO MIX TO THE SURFACE BECAUSE THE AIRMASS WILL DECOUPLE ALONG
THE FRONT RANGE.
ANOTHER BIG CONCERN WILL BE THE SNOW AND BLOWING SNOW IN THE
MOUNTAINS. AIRMASS IS QUITE DRY OVER THE NORTH CENTRAL MOUNTAINS
RIGHT NOW SO IT WILL TAKE A WHILE TO MOISTEN IT UP. MAY SEE A FEW
LIGHT SNOW SHOWERS THIS MORNING...BUT MOST LOCATIONS WILL HAVE TO
WAIT UNTIL THIS AFTERNOON FOR THE SNOW TO BEGIN. STRONG WINDS ALOFT
COMBINED WITH INCREASING MOISTURE WILL PRODUCE OROGRAPHIC SNOW.
EXPECT TO SEE A PERIOD OF MODERATE TO HEAVY SNOW THIS EVENING WHEN A
FEW FACTORS COME TOGETHER. COLD FRONT WILL PUSH ACROSS THE MOUNTAINS
EARLY THIS EVENING CAUSING WINDS TO TURN A MORE FAVORABLE NORTHWEST
DIRECTION. COLD AIR ADVECTION BEHIND THE FRONT WILL INCREASE LAPSE
RATES. THESE COMBINED WITH INCREASING MOISTURE SHOULD CREATE A
PERIOD OF WIDESPREAD MODERATE TO HEAVY SNOW. MODELS THEN SHOW RAPID
DRYING AFTER MIDNIGHT AND BY SUNDAY MORNING SNOW WILL HAVE STOPPED
MOST PLACES. WILL KEEP THE WARNINGS IN EFFECT THROUGH SUNDAY THOUGH
AS ANOTHER SURGE OF MOISTURE MOVE OVER THE MOUNTAINS AND PRODUCES
MORE SNOW ON SUNDAY.
WINTER STORM WARNINGS ARE CURRENTLY IN EFFECT FOR THE MOUNTAINS AND
ADVISORIES FOR THE VALLEYS. SNOWFALL AMOUNTS FOR THE NEXT 24 HOURS
ARE LOOKING LIKE 6-12" FOR ZONE 31...4-8 ZONE 33 AND 2-6" FOR ZONE
34. MAIN CONCERN WILL BE BLOWING AND DRIFTING SNOW DUE TO THE STRONG
WINDS. NOT CONFIDENT ENOUGH WIDESPREAD BLIZZARD CONDITIONS WILL
OCCUR TO UPGRADE TO A BLIZZARD WARNING. EXPECT SOME WIDESPREAD HARSH
CONDITIONS FOR A COUPLE HOURS BEHIND THE FRONT WITH THE MODERATE
SNOW...BUT THE SNOW WILL QUICKLY TAPER OFF. EXPOSED RIDGES SHOULD
SEE BLIZZARD CONDITIONS FOR MUCH OF THE NIGHT DUE TO VERY STRONG
WINDS ALOFT. MODELS WANT TO KEEP THE STRONG WINDS UP HIGH JUST OVER
THE RIDGES AFTER MIDNIGHT...THUS ANOTHER REASON TO NOT UPGRADE TO A
BLIZZARD WARNING AT THIS TIME.
TEMPERATURES ARE MILD NOW DUE TO THE DOWNSLOPE WINDS AND WILL REMAIN
MILD TODAY WITH HIGHS IN THE 60S FOR MOST OF NORTHEAST COLORADO. THE
FIRE DANGER WILL BE HIGH TODAY DUE TO THE STRONG WINDS. RELATIVE
HUMIDITIES ARE LOW RIGHT NOW WITH READINGS RUNNING IN THE 10-20%
RANGE. MODELS INDICATE THAT THE AIRMASS WILL MOISTEN THROUGH THE DAY
AND PUSH HUMIDITIES ABOVE 15%. THEREFORE WILL NOT ISSUE ANY RED FLAG
WARNING. IF THE DRY AIRMASS IS SLOW TO MOVE OUT A RED FLAG WARNING
WILL BE NEED FOR THE PLAINS.
.LONG TERM...THE WEATHER ROLLER COASTER CONTINUES SUNDAY WITH
ANOTHER BOUT OF SNOW AND STRONG W-NWLY WINDS FOR THE HIGH COUNTY AND
GUSTY AND ERRATIC CHINOOK WINDS FOR THE FRONT RANGE AND NEARBY
PLAINS. BROAD UPPER TROUGH WITHIN THE NRN STREAM OF VERY STRONG
W/NWLY FLOW ALOFT IS TETHERED TO A CLOSED LOW AT MID-LEVELS OFF THE
NRN BAJA COAST. THE UPR TROUGH PASSES OVER COLORADO DURING THE DAY
SUNDAY. MODEL CROSS SECTIONS SHOW A DEEP LAYER OF MARGINALLY
UNSTABLE SATURATED AIR FROM THE CONTINENTAL DIVIDE WESTWARD DURING
THE MORNING AND EARLY AFTERNOON HOURS. BY LATE IN THE DAY THE DEPTH
OF THE MOIST LAYER BEGINS TO DECREASE WITH INCREASING SUBSIDENCE AND
STABILITY ON THE BACK SIDE OF THE EXITING UPPER TROUGH. 750-500 MB
WINDS PREDOMINANTLY WESTERLY IN DIRECTION THROUGH THE DAY SUNDAY
WITH SPEEDS AT 700MB ON THE ORDER OF 40-45KTS....AND UP AROUND 80
KTS ABOVE TIMBERLINE SUNDAY MORNING. AFTER 18Z/SUN MODEL WIND SPDS
DECREASE BUT REMAIN ZONAL...ONLY TO INCREASE AGAIN SUNDAY NIGHT WITH
STRONG MID-UPPER LEVEL SUBSIDENCE OVER THE FRONT RANGE. OVERNIGHT
THE I-25 URBAN CORRIDOR COULD SEE STG AND GUSTY COLD BORA TYPE
DOWNSLOPE WINDS DEVELOPING WITH COLD AIR ADVECTION KICKING IN WITH
PASSAGE OF A WEAK SECONDARY TROUGH AXIS. PERIOD OF STRONGEST WINDS
OVER AND ALONG THE FRONT RANGE APPEARS TO BE FROM 06Z/MON TO
18Z/MON. AT THIS TIME...SPEEDS DO NOT APPEAR TO REACH HIGH WIND
CRITERIA...BUT WOULDN/T BE SURPRISED IF WE HEAR OF A FEW WIND PRONE
AREAS HITTING IT TOWARDS MORNING. ON MONDAY AIRMASS DRIES OUT WITH
MODERATE NWLY FLOW ALOFT. MOISTURE BANKED UP AGAINST THE MTNS WEST
OF THE CONT DIVIDE COULD KEEP SNOW SHOWERS GOING FOR A GOOD PART OF
THE DAY...BUT RESULTING IN LITTLE IF ANY ADDITIONAL ACCUMULATION.
DOWNSLOPE FLOW OFF THE FRONT RANGE ON MONDAY IS EXPECTED TO KEEP
DAYTIME TEMPS ON THE MILD SIDE WITH HIGHS IN THE LOWER/MID 50S ON
THE PLAINS. THAT/S ABOUT AVERAGE FOR THE DATE. SHOULD ALSO SEE
PLENTY OF SUNSHINE EAST OF THE MTNS THAT DAY.
LOOKING AHEAD...MODELS SHOW YET ANOTHER BATCH OF PACIFIC MOISTURE
RACING SEWRD ACROSS THE REGION ON TUESDAY. THE NORTHERN MTNS COULD
SEE A RESURGENCE IN SNOW SHOWER ACTIVITY DURING THE DAY...BUT ANY
ACCUMULATION SHOULD BE MINOR AND MAINLY CONFINED TO NORTHWEST SLOPES
NORTH OF I-70. OTHERWISE SHOULD SEE MORE MID-LEVEL CLOUD COVER EAST
OF THE MTNS ON TUESDAY...AND WITH COOLING ALOFT SHOULD SEE THE
COOLEST TEMPERATURES OF THE WEEK ON TUESDAY. STILL ABOUT AVERAGE FOR
THE DATE. MODELS SHOWS DRYING OVERNIGHT AND WINDS EASING AS THE JET
STREAM SHIFTS NORTHWARD WITH A BROAD ZONAL FLOW PATTERN SETTING UP
OVER THE WESTERN CONUS. REST OF THE WEEK LOOKS DRY WITH PERIODS OF
GUSTY WINDS AND SLIGHTLY ABOVE AVERAGE TEMPERATURES THE RULE.
&&
.AVIATION...A SURFACE TROUGH OVER THE EASTERN PLAINS OF COLORADO
WILL KEEP WINDS WEST TO SOUTHWEST THROUGH THE DAY TODAY. WINDS WILL
BECOME GUSTY DUE TO STRONG WINDS ALOFT. THE STRONGEST WINDS AT KDEN
AND KAPA WILL BE 20-03Z. A COLD FRONT WILL PUSH THROUGH THE AREA
THIS EVENING CAUSING WINDS TO SHIFT NORTHWEST. AFTER 06Z...WINDS
WILL BECOME EASTERLY AS A SURFACE MOVES IN BEHIND THE FRONT. ONLY
EXPECT MID AND HIGH CLOUDS THROUGH TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 6 PM MST THIS EVENING FOR COZ035-036-038-
039.
WINTER STORM WARNING FROM NOON TODAY TO MIDNIGHT MST SUNDAY
NIGHT FOR COZ031-033-034.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 5 PM MST
SUNDAY FOR COZ030-032.
&&
$$
SHORT TERM...MEIER
LONG TERM....BAKER
AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS DENVER CO
811 PM MST FRI NOV 11 2011
.UPDATE...
&&
.SHORT TERM...A MTN WAVE IS SUPPOSED TO DVLP BY 09Z AND LINGER
THRU 15Z SAT MORNING. LATEST RUC SHOWS PEAK GUSTS IN THE 50-60 MPH
RANGE LATE TONIGHT IN AND NR THE FOOTHILLS WHILE THE NAM HAS
HIGHER GUSTS IN THE 65-75 MPH RANGE ALTHOUGH IT KEEPS THE
STRONGEST WINDS MAINLY IN THE HIGHER FOOTHILLS AND OVER THE MTNS.
MEANWHILE THE HRRR HAS WIND GUSTS MAINLY IN THE 55-65 MPH RANGE.
WILL LEAVE CURRENT WARNING IN PLACE SINCE MAY STILL SEE A FEW
HIGHER GUSTS MIX DOWN TO LOWER AREAS IN THE NORMALLY WINDY AREAS.
.AVIATION...WILL KEEP WINDS SSW OVERNIGHT AROUND 10-15 MPH HOWEVER
LATEST HRRR SHOWS WINDS MAY PICK UP AFTER 09Z FM THE WSW WITH SOME
GUSTS TO 20-25 MPH THRU 13Z OR S0. THUS WILL INCLUDE A TEMPO GROUP
FOR WIND GUSTS IN THE 06Z TAF.
&&
.PREV DISCUSSION... /ISSUED 303 PM MST FRI NOV 11 2011/
SHORT TERM...AS THE NEXT STORM SYSTEM FROM THE PACIFIC NORTHWEST
APPROACHES THE STATE TONIGHT...A STRONG SURFACE GRADIENT DEVELOPS AS
A SURFACE TROUGH DEEPENS ALONG THE LEESIDE OF THE ROCKIES. MODEL
CROSS SECTIONS CONTINUE TO SHOW WINDS INCREASING AFTER MIDNIGHT
THROUGH SATURDAY MORNING HOURS AND HAVE THE TREND AS STRONGER THAN
LAST NIGHT WHERE WE SAW GUSTS TO 74 MPH IN THE FOOTHILLS OF BOULDER
COUNTY AND TO 79 MPH OVER BERTHOUD PASS. WILL CONTINUE THE HIGH WIND
WARNING FOR THE FOOTHILLS AND URBAN CORRIDOR MAINLY WEST OF I25
STARTING AFTER MIDNIGHT THROUGH SATURDAY AFTERNOON. SOME RECENT
MODELS ARE SHOWING THE MAIN TIME FRAME OF STRONGEST WINDS A LITTLE
LATER...BUT WILL KEEP WHAT IS OUT AS STILL EXPECTING THE NORMAL
EARLY MORNING MAXIMUM GUST PATTERN.
MOISTURE WILL BE INCREASING OVER WESTERN COLORADO TONIGHT WITH SNOW
EXPECTED TO BEGIN OVER THE NORTHERN MOUNTAINS AFTER MIDNIGHT TONIGHT
WITH GENERALLY LIGHT AMOUNTS...THEN SNOW RATES ARE EXPECTED TO
INCREASE THROUGH THE REST OF THE MORNING AND TOMORROW AFTERNOON AS
THE UPPER DISTURBANCE NEARS. STRONG OROGRAPHIC FORCING AS WELL AS
DYNAMIC FORCING FROM THE DISTURBANCE PASSING OVERHEAD IS EXPECTED TO
BRING HEAVIER SNOWFALL BEGINNING TOMORROW AFTERNOON. 4 TO 7 INCHES
ARE EXPECTED TOMORROW OVER THE MOUNTAINS OF WESTERN GRAND AND
JACKSON COUNTIES...WITH AMOUNTS OF 3 TO 6 INCHES OVER THE REST OF
THE WESTERN FACES OF THE NORTHERN AND CENTRAL MOUNTAINS. THE FORCING
IN THE MORNING WILL BE MAINLY OROGRAPHIC LIMITING THE HIGH VALLEYS
OF GETTING MUCH SNOW UNTIL THE UPPER SHORTWAVE MOVES CLOSER IN THE
AFTERNOON. EXPECT A FEW INCHES POSSIBLE OVER NORTH AND MIDDLE PARKS
BY THE EVENING. WINDS IN EXCESS OF 40 MPH WITH GUSTS UP TO 75 MPH
WILL CAUSE EXTENDED PERIODS OF BLIZZARD CONDITIONS ABOVE TREE LINE.
THESE HIGHER WINDS HAVE THE POTENTIAL TO DIG FURTHER DOWN OVER THE
PASSES AT TIMES TO CAUSE BLIZZARD CONDITIONS FOR A SHORT TIME.
THE PLAINS ARE EXPECTED TO BE GENERALLY WINDY TOMORROW WITH THE
STRONG WEST WINDS SPREADING OVER THE EASTERN PLAINS IN THE
AFTERNOON. HIGHS WILL BE SIMILAR TO TODAY`S OVER THE FAR EASTERN
PLAINS WITH A FEW DEGREES COOLING CLOSER TO THE FOOTHILLS.
LONG TERM...SHORT WAVE TROUGH AXIS AND BEST Q-G VERTICAL MOTION
WILL BE PASSING ACROSS THE FORECAST AREA BY EARLY SATURDAY EVENING.
THEN BETTER COLD ADVECTION WILL OCCUR IN THE MOUNTAINS WITH THE
WINDS SHIFTING ALMOST DUE WESTERLY. WHILE THIS IS NOT A TERRIFIC
SETUP FOR OROGRAPHIC SNOWFALL IN THE HIGH COUNTRY...LAPSE RATES ARE
NEARLY MOIST ADIABATIC ALLOWING FOR GOOD OROGRAPHIC RESPONSE
ESPECIALLY CONSIDERING THE 40 KNOTS OF CROSS MOUNTAIN WIND. THERE
SHOULD ALSO BE A 2 TO 3 HOUR PERIOD OF RATHER HEAVY SNOWFALL
ASSOCIATED WITH THE ONSET OF COLD ADVECTION. IN ADDITION...WINDS
WILL BE HOWLING ESPECIALLY ABOVE TIMBERLINE WITH GUSTS TO 70 MPH OR
MORE LEADING TO CONSIDERABLE BLOWING AND DRIFTING SNOW AND NEAR
BLIZZARD CONDITIONS ESPECIALLY DURING THE PERIOD OF HEAVIER
SNOWFALL. THERE SHOULD BE A DECREASE IN SNOW DURING THE OVERNIGHT
HOURS SATURDAY NIGHT AS SHORT WAVE CONTINUES TO PUSH EASTWARD AND
SOME DRY AIR WORKS INTO THE STATE. HOWEVER...ANOTHER SHOT OF
MOISTURE NOW SEEN STREAMING ACROSS THE ALEUTIANS WILL REACH THE
STATE BY SUNDAY MORNING. THIS WILL BRING ANOTHER INCREASE IN
SNOWFALL WHICH SHOULD CONTINUE THROUGH THE DAY BEFORE DECREASING
SUNDAY EVENING. OROGRAPHIC SNOW MODELS SHOWS ANOTHER 4-8 INCHES OF
SNOW FOR THIS PERIOD SO GOING WEEKEND STORM TOTAL FORECAST OF 8-16
INCHES IN THE FRONT RANGE MOUNTAINS AND FOOTHILLS...AND 12-24 INCHES
NEAR THE RABBIT EARS PASS AREA IS ON TRACK. WE WILL CONTINUE ALL
WINTER STORM WARNINGS AS PREVIOUSLY ISSUED.
WITH REGARD TO THE WIND...THERE IS SOME THREAT OF HIGH WINDS INTO
SATURDAY EVENING AS SUBSIDENCE DEVELOPS BEHIND THE UPPER LEVEL
TROUGH. THIS STILL LOOKS LIKE MORE OF A BRUTE FORCE EVENT RATHER
THAN A MOUNTAIN WAVE EVENT WITH LACK OF A MOUNTAIN TOP STABLE
LAYER. GIVEN THE LACK OF CONFIDENCE...WE WILL REFRAIN FROM
EXTENDING THE WIND WARNING INTO SATURDAY EVENING AT THIS TIME.
EVEN THOUGH SNOW AND WINDS WILL GRADUALLY DECREASE SUNDAY NIGHT...
THERE WILL STILL BE PERIODS OF GUSTY WINDS AND MOUNTAIN SNOW SHOWERS
OFF AN ON THROUGH AT LEAST TUESDAY NIGHT. WE WILL ALSO HAVE TO
WATCH POTENTIAL FOR SHORT LIVED WIND EVENTS GIVEN THE STRENGTH OF
THE FLOW ALOFT AND BETTER POTENTIAL FOR MOUNTAIN WAVE ENHANCEMENT AS
MOUNTAIN TOP STABLE LAYER SHOULD GRADUALLY STRENGTHEN. BY
WEDNESDAY...EASING FLOW ALOFT...GRADIENT...AND UPPER RIDGING SHOULD
BRING MORE TRANQUIL WEATHER. NEXT CHANCE OF SNOW SHOULD REACH THE
MOUNTAINS BY THURSDAY NIGHT/FRIDAY AS A BROAD UPPER LEVEL TROUGH
CARVES OUT ACROSS THE U.S.
AVIATION...VFR CONDITIONS ARE EXPECTED...WITH SCT-BKN HIGH CLOUDS
FROM A STANDING WAVE CLOUDS. A SURFACE TROUGH HAS BASICALLY SET UP
RIGHT OVER KDEN WITH A FEW BOUNDARIES TO THE NORTH AND SOUTH.
SURFACE WINDS SHOULD REMAIN SOUTHEASTERLY AT KDEN AND KAPA WITH
SPEEDS LESS THAT 10 KTS UNTIL AN ENHANCED DRAINAGE WINDS KICK IN
THIS EVENING. WINDS ARE THEN EXPECTED TO BECOME WEST TOMORROW
MORNING WITH SPEEDS OF 15 TO 30 MPH ANTICIPATED IN THE AFTERNOON.
KBJC SHOULD BECOME WESTERLY THIS EVENING WITH SPEEDS INCREASING
THROUGH THE NIGHT INTO SATURDAY WITH SPEEDS OF 30 TO 50 MPH EXPECTED.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM MIDNIGHT TONIGHT TO 6 PM MST SATURDAY FOR
COZ035-036-038-039.
WINTER STORM WARNING FROM NOON SATURDAY TO MIDNIGHT MST SUNDAY
NIGHT FOR COZ031-033-034.
WINTER WEATHER ADVISORY FROM 3 PM SATURDAY TO 5 PM MST SUNDAY
FOR COZ030-032.
&&
$$
SHORT TERM...RPK
LONG TERM....BARJENBRUCH
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS DENVER CO
828 PM MST THU NOV 10 2011
.UPDATE...
&&
.SHORT TERM...MTN WAVE WAS DEVELOPING AND IS FCST TO REMAIN IN
PLACE OVERNIGHT SO HAVE INCREASED WINDS SOME IN AND NR THE
FOOTHILLS OVERNIGHT. WINDS SHOULD STAY BLO WARNING CRITERIA BUT A
FEW GUSTS FROM 60-65 MPH WILL CERTAINLY BE POSSIBLE.
.AVIATION...WINDS SHOULD BECOME SSW BY 05Z AND REMAIN THAT WAY
THRU FRU MORNING.
&&
.PREV DISCUSSION... /ISSUED 240 PM MST THU NOV 10 2011/
SHORT TERM...MODERATE NORTHWEST FLOW ALOFT ACROSS COLORADO WITH
UPPER LEVEL RIDGE OVER GREAT BASIN. CURRENTLY SOME WIND GUSTS TO
40 MPH OVER THE HIGHER MOUNTAIN PASSES. MODELS SHOW RIDGE MOVING
EAST ACROSS WESTERN COLORADO OVERNIGHT...WITH FLOW ALOFT BECOMING A
BIT MORE WESTERLY. BOTH NAM AND RUC CROSS SECTIONS INDICATE A WEAK
MOUNTAIN WAVE DEVELOPING OVERNIGHT...WITH CROSS MOUNTAIN FLOW
INCREASING TO AROUND 35 KTS. MAY SEE SOME GUSTS REACHING 50 MPH OVER
THE HIGHER RIDGES OVERNIGHT WITH GUSTS TO 40 MPH ALONG THE
FOOTHILLS. WILL BOOST THE WIND GRIDS A BIT OVERNIGHT. AS FOR
PLAINS...SHOULD SEE SOME ENHANCED DRAINAGE FLOW NEAR FOOTHILLS
TONIGHT WITH LIGHT WINDS ELSEWHERE AS AIRMASS DECOUPLES. WRF
SYNTHETIC SATELLITE IMAGERY SUGGESTS AN INCREASE IN WAVE CLOUD ALONG
FOOTHILLS OVERNIGHT. MAY BE A BIT OVERDONE...BUT WILL ADD A BIT MORE
CLOUD TO THE GRIDS. ON FRIDAY...MODERATE WESTERLY FLOW ALOFT TO
PREVAIL ACROSS REGION AS RIDGE SHIFTS INTO EASTERN COLORADO. NAM
CROSS SECTIONS SHOW CROSS MOUNTAIN FLOW INCREASES TO AROUND 40 KTS
AT MOUNTAIN TOP BY THE AFTERNOON. WILL NEED TO INCREASE THE WINDS A
BIT FOR THE MOUNTAINS AND FOOTHILLS. CROSS SECTIONS SHOW GRADUAL
SOME INCREASE IN MID AND HIGH LEVEL MOISTURE THROUGH THE DAY. NO
PRECIPITATION THROUGH FRIDAY. MODELS HINT AT A SURFACE DENVER
CYCLONE DEVELOPING BY THE AFTERNOON...WITH WEAK EASTERLY WINDS
ACROSS THE DENVER AREA. WILL ADJUST WINDS ACCORDINGLY. FORECAST
SOUNDS AS WELL AS GUIDANCE INDICATING HIGHS IN THE MID 50S TO MID
60S ACROSS THE PLAINS. CURRENT TEMPERATURE GRIDS IN LINE WITH
GUIDANCE AND LOOK REASONABLE. LITTLE CHANGES NEEDED AT THIS POINT.
HUMIDITY WILL BE LOW ACROSS THE PLAINS FRIDAY AFTERNOON...BUT WINDS
SHOULD PRECLUDE ANY RED FLAG HILITE.
LONG TERM...MAIN CONCERN WILL BE THE HIGH WIND POTENTIAL OVER EAST
SLOPES AND FRONT RANGE FOOTHILLS THIS WEEKEND ALONG WITH SNOW
POTENTIAL FOR THE MOUNTAINS FOR BOTH SATURDAY AND SUNDAY. THE RIDGE
ALOFT WILL FLATTEN ON FRIDAY AS THE FLOW ALOFT BACKS AROUND MORE
WESTERLY. A VIGOROUS UPPER LEVEL TROF WHICH IS NOW OVER ALASKA WILL
SWEEP ACROSS THE NORTHERN ROCKY MOUNTAIN STATES ON SATURDAY.
WESTERLY WINDS WILL INCREASE SUBSTANTIALLY LATE FRIDAY NIGHT AND
SATURDAY ACROSS COLORADO. THIS APPEARS LIKE A GOOD SETUP FOR A HIGH
WIND EVENT OVER OUR EAST SLOPES AS CROSS BARRIER FLOW OFF THE LATEST
NAM INCREASES TO 60 TO 80KT ON THE HIGHER EAST SLOPES. THE 12Z NAM
EVEN SHOWED 100KT OF WEST FLOW AROUND 700MB. I DON`T BELIEVE I HAVE
EVER SEEN A NUMBER THAT HIGH. GIVEN THE IMPACT OF THIS EVENT OVER
ALASKA THIS MIGHT BE SOMETHING TO MONITOR CLOSELY. THE SHEAR AND
STABILITY PROFILE ALSO LOOK GOOD FROM MOUNTAIN WAVE AMPLIFICATION.
LOCAL SANGSTER WINDS ALSO SHOW AREA FLIRTING IN THE WATCH/WARNING
WINDOW FOR LATE FRIDAY NIGHT AND SATURDAY. WILL GO WITH A HIGH WIND
WATCH FOR THE FRONT RANGE FOOTHILLS AND ADJ PLAINS FOR LATE FRI NITE
AND SATURDAY. THE WINDS SHOULD DECREASE LATE SATURDAY AS COLD FRONT
SWEEPS ACROSS AS MTN TOP INVERSION LAYER GOES AWAY AND PRECIP
INCREASES ALONG AND WEST OF THE DIVIDE. THERE MAY BE A SECONDARY
WINDY PERIOD LATE SATURDAY NIGHT AND SUNDAY WITH STRONG MID LEVEL
WARMING OCCURRING BEHIND THE TROF. TO KEEP THINGS SIMPLE WILL JUST
WORRY ABOUT ONE EVENT AT A TIME.
AS FOR THE SNOW POTENTIAL...MOISTURE WILL INCREASE OVER THE
MOUNTAINS LATE FRIDAY NIGHT AND SATURDAY. THIS SHOULD MAKE FOR A
GOOD OROGRAPHIC SNOW EVENT WITH 700MB WINDS IN THE 35-45KT RANGE.
WINDS WILL INITIALLY FAVOR ZONES 31..33 AND THEN EFFECT ZONE 34 MORE
AS WINDS SHIFT MORE WESTERLY BY SAT AFTERNOON. MOISTURE CONTINUES
WELL INTO SUNDAY AFTERNOON. WILL THEN GO WITH A WINTER STORM WATCH
FOR ALL OUR MOUNTAIN ZONES OF 31..33..34 FOR THE WEEKEND. THERE WILL
BE BREAKS AT TIMES BUT WILL BE HARD TO PINPOINT EXACT TIMING.
FOR MUCH OF NEXT WEEK COLORADO WILL BE UNDER A STRONG NORTHWEST FLOW
PATTERN WITH WINDY PERIODS IN THE MOUNTAINS WITH A SLIGHT CHANCE OF
SNOW SHOWERS EACH DAY. ACROSS LOWER ELEVATIONS...IT WILL BE
GENERALLY DRY AND MILD WITH BREEZY CONDITIONS.
AVIATION...LIGHT SOUTH TO SOUTHWEST WINDS ACROSS AREA AIRPORTS...
WITH SOME GUSTS TO AROUND 15 KTS AT KAPA. SOUTHWEST WINDS TO
CONTINUE OVERNIGHT. SHOULD SEE SOME ENHANCED DRAINAGE WINDS BY 04Z
WITH SPEEDS AROUND 15 KTS. SOME INCREASE IN MAINLY HIGH LEVEL CLOUD
OVERNIGHT WITH VFR CONDITIONS CONTINUING. WEAK DENVER CYCLONE TO
DEVELOP BY 15Z...EXPECTED TO PERSIST THROUGH THE DAY. AS A
RESULT...WINDS TO HAVE AN EASTERLY DIRECTION WITH SPEEDS LESS THAT
10 KTS. EXCEPTION WILL BE AT KBJC WITH A WESTERLY COMPONENT
PREVAILING. VFR CONDITIONS TO PERSIST...WITH SOME MID AND HIGH LEVEL
CLOUDS.
&&
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY
AFTERNOON FOR COZ035-036-038-039.
WINTER STORM WATCH FROM SATURDAY MORNING THROUGH SUNDAY
AFTERNOON FOR COZ031-033-034.
&&
$$
SHORT TERM...RPK
LONG TERM....ENTREKIN
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS ALBANY NY
107 AM EST SAT NOV 12 2011
.SYNOPSIS...
A STRONG UPPER LEVEL DISTURBANCE WILL PASS TO THE EAST OF REGION
EARLY TONIGHT...AND THE RAIN OR SNOW SHOWERS OVER THE REGION WILL
GRADUALLY TAPER OFF. DRY WEATHER...AND MILDER TEMPERATURES ARE
EXPECTED FOR THE WEEKEND AS A RIDGE OF HIGH PRESSURE BUILDS INTO THE
REGION FROM THE SOUTHWEST.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1230 AM...PARTLY TO MOSTLY CLOUDY SKIES AND COOL
TEMPERATURES PREVAILED ACROSS THE FA WITH READINGS MAINLY IN THE
30S. LAKE EFFECT ACTIVITY HAS DIMINISHED CONSIDERABLY AND THIS WILL
BE THE TREND FOR THE REMAINDER OF THE NIGHT AS WHAT IS LEFT OF THE
BAND DOWN THE MOHAWK VALLEY GRADUALLY LIFTS NORTH AND WEAKENS.
HAVE FOLLOWED THE HRRR COL MAX REF CLOSELY FOR THIS TRANSITION AND
BY LATE TONIGHT LITTLE IF ANY OF THE BAND WILL BE LEFT IN THE FA
AS THE LOW LEVEL FLOW BECOMES ANTICYLCONIC. STILL EXPECT LOW TEMPS
OVERNIGHT TO BE IN THE 20S IN MOST AREAS WITH PARTLY CLOUDY TO
MOSTLY CLOUDY SKIES WITH THE MOST CLOUDS NORTH. ANY ADDITIONAL
SNOW ACCUMULATION IS EXPECTED TO BE UNDER A QUARTER OF AN INCH AND
THIS WOULD LIKELY BE ACROSS THE WESTERN MOHAWK VALLEY AND SOUTHERN
ADIRONDACKS.
AS OF 955 PM...LAKE EFFECT ACTIVITY HAS GENERALLY CONSOLIDATED
INTO A COUPLE RELATIVELY NARROW BUT STILL SOMEWHAT LONG
BANDS...ALTHOUGH INTENSITY AND COVERAGE HAVE BEEN DECREASING IN
OUR AREA. HEAVIEST REFLECTIVITIES CONFINED TO CENTRAL NY AT THIS
TIME. THIS TREND SHOULD CONTINUE AS MIXED LAYER FLOW IS IN THE
PROCESS OF STARTING TO BACK TO A MORE WESTERLY TRAJECTORY AND
INVERSION HEIGHTS WILL BEGIN TO LOWER. SNOW BANDS WILL BECOME MORE
TRANSITORY AS FLOW IS EXPECTED TO BACK SIGNIFICANTLY OVERNIGHT.
TRENDS STILL LOOK ON TRACK FOR SNOW SHOWERS MOVING NORTH AND
GRADUALLY DISSIPATING THROUGH THE OVERNIGHT. ANY ADDITIONAL
ACCUMULATIONS FROM THIS POINT ON SHOULD BE VERY MINOR WITH
ISOLATED SPOTS UP TO AN INCH.
PREVIOUS NEAR TERM DISCUSSIONS...
AS OF 700 PM...SCATTERED TO NUMEROUS LAKE EFFECT RAIN/SNOW SHOWERS
CONTINUE ACROSS A CORRIDOR FROM MAINLY THE EXTREME SOUTHERN
ADIRONDACKS AND MOHAWK VALLEY SOUTHWARD THROUGH THE SCHOHARIE
VALLEY AND INTO THE EASTERN CATSKILLS. ACTIVITY HAS PRETTY MUCH
DEVELOPED INTO NARROW BANDS IN W-NW FLOW REGIME...RATHER THAN THE
CELLULAR CHARACTER OF SHOWERS BEFORE SUNSET. SOME OF THE MORE
PERSISTENT BANDS HAVE RESULTED IN ACCUMULATIONS OF 1-3
INCHES...ESPECIALLY FOR ELEVATIONS ABOVE 1000 FEET ACROSS THE
SOUTHERN HERKIMER COUNTY IN THE SAWTOOTH AS WELL AS IN PORTIONS OF
SCHOHARIE COUNTY. LOCAL HIRESWRF AND HRRR SHOWING NARROW BANDS OF
LAKE EFFECT SNOW SHOULD PERSIST THROUGH THE EVENING...ALTHOUGH THE
MIXED LAYER FLOW WILL START TO SHIFT TO MORE OF A WESTERLY
TRAJECTORY LATER THIS EVENING...THEN SOUTHWEST OVERNIGHT. THIS
WILL ALLOW BANDS TO TRANSLATE NORTHWARD SO THAT AREAS THAT ARE
EXPERIENCING ACTIVITY NOW WILL LIKELY TAPER OFF WITHIN A FEW HOURS
THIS EVENING. SO...ANY ADDITIONAL SNOW ACCUMULATIONS SHOULD BE
LIMITED TO AN INCH OR TWO AND MAINLY FOR THE AREAS PREVIOUSLY
MENTIONED. INVERSION HEIGHTS ARE EXPECTED TO LOWER OVERNIGHT...SO
ONLY A DUSTING TO A FEW TENTHS OF AN INCH CAN BE EXPECTED ACROSS
THE WESTERN ADIRONDACKS AS THE BANDS SHIFT NORTH.
AS OF 400 PM...LAKE ENHANCED MOISTURE CONTINUES TO PRODUCE
SCATTERED TO NUMEROUS RAIN/SNOW SHOWERS ACROSS THE
REGION...ESPECIALLY ACROSS HIGHER TERRAIN. NO WELL DEFINED BAND AS
OF 400 PM...BUT ACTIVITY APPEARS MORE CELLULAR. WOULD EXPECT A
BETTER DEFINED BAND WILL DEVELOP THIS EVENING AS DAYTIME HEATING
WANES. THIS BAND WOULD ALSO BE SHIFTING STEADILY NORTH DURING THE
NIGHT AND WEAKENING AS THE INVERSION BEGINS TO LOWER. LIKELY POPS
OVER THE WESTERN MOHAWK VALLEY AND SCHOHARIE VALLEY TO START THE
EVENING...WITH CHANCE TO SLIGHT CHANCE POPS ELSEWHERE. THESE POPS
ARE FORECAST TO SLOWLY DECREASE DURING THE NIGHT...REACHING ONLY
SLIGHT CHANCE POPS OVER THE SOUTHERN AND WESTERN ADIRONDACKS BY
SUNRISE SATURDAY. GUSTY SURFACE WINDS THIS EVENING WILL SLOWLY
DIMINISH TONIGHT...BUT AT LEAST A BREEZE SHOULD CONTINUE IN ALL OR
MOST AREAS. LOWS WILL BE IN THE 20S TO AROUND 30.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH SUNDAY NIGHT/...
LINGERING ISOLATED SNOW SHOWERS OVER THE SOUTHERN/WESTERN
ADIRONDACKS DURING SATURDAY MORNING...THEN DRY SATURDAY AFTERNOON
THROUGH SUNDAY AS THE EFFECTS OF A LARGE HIGH PRESSURE SYSTEM
MOVING OFF THE SOUTHEASTERN STATES BEGINS TO DOMINATE THE WEATHER
OVER THE REGION. THE POSITION OF THE HIGH AS IT MOVES OFF THE COAST
WILL ALSO RESULT IN A SOUTH TO SOUTHWEST FLOW OF MILDER AIR ON
SATURDAY...AND ESPECIALLY ON SUNDAY. HIGHS SATURDAY WILL BE IN THE
MID 40S TO MID 50S...LOWS SATURDAY NIGHT IN THE MID 20S TO MID
30S....AND HIGHS SUNDAY IN THE MID 50S TO AROUND 60.
FOR SUNDAY NIGHT...A WEAK FRONT APPROACHING FROM THE WEST MAY ALLOW
FOR SHOWERS TO DEVELOP LATE SUNDAY NIGHT...AND HAVE INDICATED ABOUT
A 40 PERCENT CHANCE OF SHOWERS AFTER MIDNIGHT. CLOUDS AND SOME WIND
SHOULD KEEP TEMPS QUITE MILD...ONLY FALLING TO BETWEEN 40 AND THE
MID 40S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
THERE IS STILL SOME DISCREPANCIES AMONGST THE LONG RANGE MODELS
IN THE TIMING OF SYSTEMS. HOWEVER...THE BIG PICTURE IS SIMILAR. IT
LOOKS AS THE POSITIVE NORTH ATLANTIC OSCILLATION/NEGATIVE PACIFIC
PATTERN WILL CONTINUE. WHAT THIS MEANS IS THAT TROUGHINESS IS
FAVORED ON THE WEST COAST OF THE US WHILE RIDGING IS FAVORED ON THE
EAST COAST.
MONDAY...THE GFS HAS A WEAK STALLED OUT FRONT DEPICTED TO THE SOUTH
OF OUR REGION. AT THE SAME TIME THE ECMWF AND CMC HAVE THIS FEATURE
FURTHER NORTH. EITHER WAY...THERE APPEARS TO BE A MARGINAL THREAT
FOR SHOWERS ON MONDAY. TEMPERATURES WILL LIKELY BE IN THE 50S...TO
AROUND
60 IN THE HUDSON VALLEY ON SOUTHWARD...ABOUT 10 DEGREES ABOVE
NORMAL.
THE SAME FRONT WILL CONTINUE TO BE THE CHALLENGE INTO TUESDAY. THE
GFS SLOWLY PUSHES THE FRONT FURTHER SOUTH AND EAST. HOWEVER...THE
CMC AND ECMWF FORECAST A WAVE TO FORM ALONG IT...THEN MOVE THROUGH
LATER ON TUESDAY. WILL CONTINUE CHANCES THROUGH TUESDAY...WITH
TEMPERATURES AGAIN REACHING 55 TO AROUND 60 DEGREES. WE WILL
CONTINUE WITH CHANCES FOR RAIN SHOWERS.
BY WEDNESDAY AND THURSDAY...ALL MODELS INDICATE A COOLER AIR MASS
MOVES FROM THE NORTHWEST. H850 TEMPERATURES DROP FROM ABOUT +8C TO
WELL BELOW 0C. IT LOOKS COLD ENOUGH FOR ANOTHER LAKE RESPONSE
ALTHOUGH THE OVERALL FLOW IS SOMEWHAT ANTICYCLONIC. FOR
NOW...CONFINE ANY CHANCES OF LAKE EFFECT TO THE HIGHER TERRAIN AND
KEEP IT OUT OF THE HUDSON VALLEY ON WEDNESDAY ONLY.
TEMPERATURES LOOK TO CHILL BACK TO NORMAL LEVELS...45-50 FOR HIGHS
AND LOWS IN THE 30S.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
FLIGHT CONDITIONS SHOULD MOSTLY BE VFR ACROSS THE REGION DURING
THE TAF PERIOD ENDING 06Z SUNDAY...HOWEVER A BAND OF LAKE EFFECT
MOISTURE WILL RESULT IN A BAND OF MVFR TO IFR CIGS ABOUT 25 SM
WIDE EXTENDING FROM EASTERN LAKE ONTARIO ESE TOWARD THE CAPITAL
DISTRICT BETWEEN 06Z AND AROUND 10Z. THIS BAND RESULTED IN IFR
CONDITIONS AT KRME DUE TO LOW CIG. AT KALB THERE MAY BE SOME
BRIEF PERIODS OF MVFR CIG...PERHAPS A BRIEF -SHSN/-SHPL BUT
VISBY SHOULD REMAIN VFR. LOCAL IFR CONDS MAY ALSO BE ENCOUNTERED
ACROSS THE HIGHER TERRAIN NORTH/SOUTH OF THE MOHAWK VALLEY AND
OVER THE HIGH PEAKS OF THE CATSKILLS...WITH MVFR-IFR CIGS OVER
THE HIGHER TERRAIN OF SRN VT AND WRN MASS.
THE BAND IS EXPECTED TO WEAKEN AND EVENTUALLY DISSIPATE AS
THE CIRCULATION BECOMES MORE ANTICYCLONIC AND WARMER AIR COMES
INTO THE REGION FROM THE OHIO VALLEY. AFTER THE SUN COMES UP
VFR CONDITIONS WILL PREVAIL WITH BKN MIDLEVEL CLDS BECOMING
SCTD LATER THIS MORNING.
WINDS DURING THE PREDAWN PERIOD WILL BE WEST OR SOUTHWEST
4 TO 8 KNOTS GRADUALLY TURNING TO A MORE SOUTHERLY DIRECTION.
LATER THIS MORNING THEY WILL PICK UP TO BETWEEN 8 AND 10 KNOTS
WITH GUSTS TO AROUND 20 KNOTS DURING THE MIDDAY PERIOD...THEN
DIMINISH TO LESS THAN 8 KNOTS DURING THE LATE AFTERNOON AND
EARLY EVENING HOURS.
OUTLOOK...
TONIGHT-SUN...VFR. NO SIG WX.
MON...VFR. SLIGHT CHC -SHRA.
TUE...VFR. CHC -SHRA.
WED...VFR. SLIGHT CHC -SHRA.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE ANTICIPATED FOR THE NEXT 5 DAYS ON THE MAIN
STEM RIVERS.
ANY PRECIPITATION THAT WILL FALL THROUGH TONIGHT WILL BE LIGHT...
GENERALLY UNDER A TENTH OF AN INCH. SOME OF THIS WILL FALL AS SNOW
ACROSS THE HIGHER TERRAIN.
SHOWERS WILL BE POSSIBLE SUNDAY NIGHT INTO MONDAY...BUT AMOUNTS
ARE EXPECTED TO REMAIN LIGHT. ADDITIONAL THREATS FOR SHOWERS WILL
CONTINUE INTO THE MIDDLE OF NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM
NEAR TERM...GJM/11/JPV
SHORT TERM...GJM
LONG TERM...HWJIV
AVIATION...RCK
HYDROLOGY...GJM
AREA FORECAST DISCUSSION
NWS ALBANY NY
1233 AM EST SAT NOV 12 2011
.SYNOPSIS...
A STRONG UPPER LEVEL DISTURBANCE WILL PASS TO THE EAST OF REGION
EARLY TONIGHT...AND THE RAIN OR SNOW SHOWERS OVER THE REGION WILL
GRADUALLY TAPER OFF. DRY WEATHER...AND MILDER TEMPERATURES ARE
EXPECTED FOR THE WEEKEND AS A RIDGE OF HIGH PRESSURE BUILDS INTO THE
REGION FROM THE SOUTHWEST.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1230 AM...PARTLY TO MOSTLY CLOUDY SKIES AND COOL
TEMPERATURES PREVAILED ACROSS THE FA WITH READINGS MAINLY IN THE
30S. LAKE EFFECT ACTIVITY HAS DIMINISHED CONSIDERABLY AND THIS WILL
BE THE TREND FOR THE REMAINDER OF THE NIGHT AS WHAT IS LEFT OF THE
BAND DOWN THE MOHAWK VALLEY GRADUALLY LIFTS NORTH AND WEAKENS.
HAVE FOLLOWED THE HRRR COL MAX REF CLOSELY FOR THIS TRANSITION AND
BY LATE TONIGHT LITTLE IF ANY OF THE BAND WILL BE LEFT IN THE FA
AS THE LOW LEVEL FLOW BECOMES ANTICYLCONIC. STILL EXPECT LOW TEMPS
OVERNIGHT TO BE IN THE 20S IN MOST AREAS WITH PARTLY CLOUDY TO
MOSTLY CLOUDY SKIES WITH THE MOST CLOUDS NORTH. ANY ADDITIONAL
SNOW ACCUMULATION IS EXPECTED TO BE UNDER A QUARTER OF AN INCH AND
THIS WOULD LIKELY BE ACROSS THE WESTERN MOHAWK VALLEY AND SOUTHERN
ADIRONDACKS.
AS OF 955 PM...LAKE EFFECT ACTIVITY HAS GENERALLY CONSOLIDATED
INTO A COUPLE RELATIVELY NARROW BUT STILL SOMEWHAT LONG
BANDS...ALTHOUGH INTENSITY AND COVERAGE HAVE BEEN DECREASING IN
OUR AREA. HEAVIEST REFLECTIVITIES CONFINED TO CENTRAL NY AT THIS
TIME. THIS TREND SHOULD CONTINUE AS MIXED LAYER FLOW IS IN THE
PROCESS OF STARTING TO BACK TO A MORE WESTERLY TRAJECTORY AND
INVERSION HEIGHTS WILL BEGIN TO LOWER. SNOW BANDS WILL BECOME MORE
TRANSITORY AS FLOW IS EXPECTED TO BACK SIGNIFICANTLY OVERNIGHT.
TRENDS STILL LOOK ON TRACK FOR SNOW SHOWERS MOVING NORTH AND
GRADUALLY DISSIPATING THROUGH THE OVERNIGHT. ANY ADDITIONAL
ACCUMULATIONS FROM THIS POINT ON SHOULD BE VERY MINOR WITH
ISOLATED SPOTS UP TO AN INCH.
PREVIOUS NEAR TERM DISCUSSIONS...
AS OF 700 PM...SCATTERED TO NUMEROUS LAKE EFFECT RAIN/SNOW SHOWERS
CONTINUE ACROSS A CORRIDOR FROM MAINLY THE EXTREME SOUTHERN
ADIRONDACKS AND MOHAWK VALLEY SOUTHWARD THROUGH THE SCHOHARIE
VALLEY AND INTO THE EASTERN CATSKILLS. ACTIVITY HAS PRETTY MUCH
DEVELOPED INTO NARROW BANDS IN W-NW FLOW REGIME...RATHER THAN THE
CELLULAR CHARACTER OF SHOWERS BEFORE SUNSET. SOME OF THE MORE
PERSISTENT BANDS HAVE RESULTED IN ACCUMULATIONS OF 1-3
INCHES...ESPECIALLY FOR ELEVATIONS ABOVE 1000 FEET ACROSS THE
SOUTHERN HERKIMER COUNTY IN THE SAWTOOTH AS WELL AS IN PORTIONS OF
SCHOHARIE COUNTY. LOCAL HIRESWRF AND HRRR SHOWING NARROW BANDS OF
LAKE EFFECT SNOW SHOULD PERSIST THROUGH THE EVENING...ALTHOUGH THE
MIXED LAYER FLOW WILL START TO SHIFT TO MORE OF A WESTERLY
TRAJECTORY LATER THIS EVENING...THEN SOUTHWEST OVERNIGHT. THIS
WILL ALLOW BANDS TO TRANSLATE NORTHWARD SO THAT AREAS THAT ARE
EXPERIENCING ACTIVITY NOW WILL LIKELY TAPER OFF WITHIN A FEW HOURS
THIS EVENING. SO...ANY ADDITIONAL SNOW ACCUMULATIONS SHOULD BE
LIMITED TO AN INCH OR TWO AND MAINLY FOR THE AREAS PREVIOUSLY
MENTIONED. INVERSION HEIGHTS ARE EXPECTED TO LOWER OVERNIGHT...SO
ONLY A DUSTING TO A FEW TENTHS OF AN INCH CAN BE EXPECTED ACROSS
THE WESTERN ADIRONDACKS AS THE BANDS SHIFT NORTH.
AS OF 400 PM...LAKE ENHANCED MOISTURE CONTINUES TO PRODUCE
SCATTERED TO NUMEROUS RAIN/SNOW SHOWERS ACROSS THE
REGION...ESPECIALLY ACROSS HIGHER TERRAIN. NO WELL DEFINED BAND AS
OF 400 PM...BUT ACTIVITY APPEARS MORE CELLULAR. WOULD EXPECT A
BETTER DEFINED BAND WILL DEVELOP THIS EVENING AS DAYTIME HEATING
WANES. THIS BAND WOULD ALSO BE SHIFTING STEADILY NORTH DURING THE
NIGHT AND WEAKENING AS THE INVERSION BEGINS TO LOWER. LIKELY POPS
OVER THE WESTERN MOHAWK VALLEY AND SCHOHARIE VALLEY TO START THE
EVENING...WITH CHANCE TO SLIGHT CHANCE POPS ELSEWHERE. THESE POPS
ARE FORECAST TO SLOWLY DECREASE DURING THE NIGHT...REACHING ONLY
SLIGHT CHANCE POPS OVER THE SOUTHERN AND WESTERN ADIRONDACKS BY
SUNRISE SATURDAY. GUSTY SURFACE WINDS THIS EVENING WILL SLOWLY
DIMINISH TONIGHT...BUT AT LEAST A BREEZE SHOULD CONTINUE IN ALL OR
MOST AREAS. LOWS WILL BE IN THE 20S TO AROUND 30.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH SUNDAY NIGHT/...
LINGERING ISOLATED SNOW SHOWERS OVER THE SOUTHERN/WESTERN
ADIRONDACKS DURING SATURDAY MORNING...THEN DRY SATURDAY AFTERNOON
THROUGH SUNDAY AS THE EFFECTS OF A LARGE HIGH PRESSURE SYSTEM
MOVING OFF THE SOUTHEASTERN STATES BEGINS TO DOMINATE THE WEATHER
OVER THE REGION. THE POSITION OF THE HIGH AS IT MOVES OFF THE COAST
WILL ALSO RESULT IN A SOUTH TO SOUTHWEST FLOW OF MILDER AIR ON
SATURDAY...AND ESPECIALLY ON SUNDAY. HIGHS SATURDAY WILL BE IN THE
MID 40S TO MID 50S...LOWS SATURDAY NIGHT IN THE MID 20S TO MID
30S....AND HIGHS SUNDAY IN THE MID 50S TO AROUND 60.
FOR SUNDAY NIGHT...A WEAK FRONT APPROACHING FROM THE WEST MAY ALLOW
FOR SHOWERS TO DEVELOP LATE SUNDAY NIGHT...AND HAVE INDICATED ABOUT
A 40 PERCENT CHANCE OF SHOWERS AFTER MIDNIGHT. CLOUDS AND SOME WIND
SHOULD KEEP TEMPS QUITE MILD...ONLY FALLING TO BETWEEN 40 AND THE
MID 40S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
THERE IS STILL SOME DISCREPANCIES AMONGST THE LONG RANGE MODELS
IN THE TIMING OF SYSTEMS. HOWEVER...THE BIG PICTURE IS SIMILAR. IT
LOOKS AS THE POSITIVE NORTH ATLANTIC OSCILLATION/NEGATIVE PACIFIC
PATTERN WILL CONTINUE. WHAT THIS MEANS IS THAT TROUGHINESS IS
FAVORED ON THE WEST COAST OF THE US WHILE RIDGING IS FAVORED ON THE
EAST COAST.
MONDAY...THE GFS HAS A WEAK STALLED OUT FRONT DEPICTED TO THE SOUTH
OF OUR REGION. AT THE SAME TIME THE ECMWF AND CMC HAVE THIS FEATURE
FURTHER NORTH. EITHER WAY...THERE APPEARS TO BE A MARGINAL THREAT
FOR SHOWERS ON MONDAY. TEMPERATURES WILL LIKELY BE IN THE 50S...TO
AROUND
60 IN THE HUDSON VALLEY ON SOUTHWARD...ABOUT 10 DEGREES ABOVE
NORMAL.
THE SAME FRONT WILL CONTINUE TO BE THE CHALLENGE INTO TUESDAY. THE
GFS SLOWLY PUSHES THE FRONT FURTHER SOUTH AND EAST. HOWEVER...THE
CMC AND ECMWF FORECAST A WAVE TO FORM ALONG IT...THEN MOVE THROUGH
LATER ON TUESDAY. WILL CONTINUE CHANCES THROUGH TUESDAY...WITH
TEMPERATURES AGAIN REACHING 55 TO AROUND 60 DEGREES. WE WILL
CONTINUE WITH CHANCES FOR RAIN SHOWERS.
BY WEDNESDAY AND THURSDAY...ALL MODELS INDICATE A COOLER AIR MASS
MOVES FROM THE NORTHWEST. H850 TEMPERATURES DROP FROM ABOUT +8C TO
WELL BELOW 0C. IT LOOKS COLD ENOUGH FOR ANOTHER LAKE RESPONSE
ALTHOUGH THE OVERALL FLOW IS SOMEWHAT ANTICYCLONIC. FOR
NOW...CONFINE ANY CHANCES OF LAKE EFFECT TO THE HIGHER TERRAIN AND
KEEP IT OUT OF THE HUDSON VALLEY ON WEDNESDAY ONLY.
TEMPERATURES LOOK TO CHILL BACK TO NORMAL LEVELS...45-50 FOR HIGHS
AND LOWS IN THE 30S.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS GENERALLY WILL PREVAIL THROUGH THE TAF PERIOD
ENDING 00Z SUNDAY. LAKE EFFECT CLOUDS AND RAIN/SNOW SHOWERS
PERSISTING AROUND KALB THIS EVENING WITH A W-NW FLOW. SOME BRIEF
MVFR CONDITIONS CAN BE EXPECTED THROUGH MUCH OF THE
EVENING...HOWEVER THE FLOW WILL BACK TO MORE OF A WEST THEN
SOUTHWEST DIRECTION...WHICH WILL CARRY ANY LAKE EFFECT SHOWERS
NORTH OF THE AREA AND WILL ALSO WEAKEN. SKIES WILL LIKELY REMAIN
BKN AT KALB/KGFL INTO THE OVERNIGHT...THEN BECOMING SCT LATE.
GENERALLY SCT CLOUDS WILL PREVAIL AT KPOU. DRY AND TRANQUIL
CONDITIONS EXPECTED ON SATURDAY WITH A SOUTHWEST FLOW DEVELOPING.
WINDS WILL SHIFT FROM THE WEST TO THE SOUTHWEST OVERNIGHT.
INITIALLY WIND SPEEDS WILL BE AROUND 10 TO 15 KT...DECREASING TO 5
TO 10 KT OVERNIGHT. WINDS ON SATURDAY WILL BE SOUTHWEST AROUND 10
KT.
OUTLOOK...
SAT-SUN...VFR. NO SIG WX.
MON...VFR. SLIGHT CHC -SHRA.
TUE...VFR. CHC -SHRA.
WED...VFR. SLIGHT CHC -SHRA.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE ANTICIPATED FOR THE NEXT 5 DAYS ON THE MAIN
STEM RIVERS.
ANY PRECIPITATION THAT WILL FALL THROUGH TONIGHT WILL BE LIGHT...
GENERALLY UNDER A TENTH OF AN INCH. SOME OF THIS WILL FALL AS SNOW
ACROSS THE HIGHER TERRAIN.
SHOWERS WILL BE POSSIBLE SUNDAY NIGHT INTO MONDAY...BUT AMOUNTS
ARE EXPECTED TO REMAIN LIGHT. ADDITIONAL THREATS FOR SHOWERS WILL
CONTINUE INTO THE MIDDLE OF NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM
NEAR TERM...GJM/11/JPV
SHORT TERM...GJM
LONG TERM...HWJIV
AVIATION...JPV
HYDROLOGY...GJM
AREA FORECAST DISCUSSION
NWS ALBANY NY
955 PM EST FRI NOV 11 2011
.SYNOPSIS...
A STRONG UPPER LEVEL DISTURBANCE WILL PASS TO THE EAST OF REGION
EARLY TONIGHT...AND THE RAIN OR SNOW SHOWERS OVER THE REGION WILL
GRADUALLY TAPER OFF. DRY WEATHER...AND MILDER TEMPERATURES ARE
EXPECTED FOR THE WEEKEND AS A RIDGE OF HIGH PRESSURE BUILDS INTO THE
REGION FROM THE SOUTHWEST.
&&
.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
AS OF 955 PM...LAKE EFFECT ACTIVITY HAS GENERALLY CONSOLIDATED
INTO A COUPLE RELATIVELY NARROW BUT STILL SOMEWHAT LONG
BANDS...ALTHOUGH INTENSITY AND COVERAGE HAVE BEEN DECREASING IN
OUR AREA. HEAVIEST REFLECTIVITIES CONFINED TO CENTRAL NY AT THIS
TIME. THIS TREND SHOULD CONTINUE AS MIXED LAYER FLOW IS IN THE
PROCESS OF STARTING TO BACK TO A MORE WESTERLY TRAJECTORY AND
INVERSION HEIGHTS WILL BEGIN TO LOWER. SNOW BANDS WILL BECOME MORE
TRANSITORY AS FLOW IS EXPECTED TO BACK SIGNIFICANTLY OVERNIGHT.
TRENDS STILL LOOK ON TRACK FOR SNOW SHOWERS MOVING NORTH AND
GRADUALLY DISSIPATING THROUGH THE OVERNIGHT. ANY ADDITIONAL
ACCUMULATIONS FROM THIS POINT ON SHOULD BE VERY MINOR WITH
ISOLATED SPOTS UP TO AN INCH.
PREVIOUS NEAR TERM DISCUSSIONS...
AS OF 700 PM...SCATTERED TO NUMEROUS LAKE EFFECT RAIN/SNOW SHOWERS
CONTINUE ACROSS A CORRIDOR FROM MAINLY THE EXTREME SOUTHERN
ADIRONDACKS AND MOHAWK VALLEY SOUTHWARD THROUGH THE SCHOHARIE
VALLEY AND INTO THE EASTERN CATSKILLS. ACTIVITY HAS PRETTY MUCH
DEVELOPED INTO NARROW BANDS IN W-NW FLOW REGIME...RATHER THAN THE
CELLULAR CHARACTER OF SHOWERS BEFORE SUNSET. SOME OF THE MORE
PERSISTENT BANDS HAVE RESULTED IN ACCUMULATIONS OF 1-3
INCHES...ESPECIALLY FOR ELEVATIONS ABOVE 1000 FEET ACROSS THE
SOUTHERN HERKIMER COUNTY IN THE SAWTOOTH AS WELL AS IN PORTIONS OF
SCHOHARIE COUNTY. LOCAL HIRESWRF AND HRRR SHOWING NARROW BANDS OF
LAKE EFFECT SNOW SHOULD PERSIST THROUGH THE EVENING...ALTHOUGH THE
MIXED LAYER FLOW WILL START TO SHIFT TO MORE OF A WESTERLY
TRAJECTORY LATER THIS EVENING...THEN SOUTHWEST OVERNIGHT. THIS
WILL ALLOW BANDS TO TRANSLATE NORTHWARD SO THAT AREAS THAT ARE
EXPERIENCING ACTIVITY NOW WILL LIKELY TAPER OFF WITHIN A FEW HOURS
THIS EVENING. SO...ANY ADDITIONAL SNOW ACCUMULATIONS SHOULD BE
LIMITED TO AN INCH OR TWO AND MAINLY FOR THE AREAS PREVIOUSLY
MENTIONED. INVERSION HEIGHTS ARE EXPECTED TO LOWER OVERNIGHT...SO
ONLY A DUSTING TO A FEW TENTHS OF AN INCH CAN BE EXPECTED ACROSS
THE WESTERN ADIRONDACKS AS THE BANDS SHIFT NORTH.
AS OF 400 PM...LAKE ENHANCED MOISTURE CONTINUES TO PRODUCE
SCATTERED TO NUMEROUS RAIN/SNOW SHOWERS ACROSS THE
REGION...ESPECIALLY ACROSS HIGHER TERRAIN. NO WELL DEFINED BAND AS
OF 400 PM...BUT ACTIVITY APPEARS MORE CELLULAR. WOULD EXPECT A
BETTER DEFINED BAND WILL DEVELOP THIS EVENING AS DAYTIME HEATING
WANES. THIS BAND WOULD ALSO BE SHIFTING STEADILY NORTH DURING THE
NIGHT AND WEAKENING AS THE INVERSION BEGINS TO LOWER. LIKELY POPS
OVER THE WESTERN MOHAWK VALLEY AND SCHOHARIE VALLEY TO START THE
EVENING...WITH CHANCE TO SLIGHT CHANCE POPS ELSEWHERE. THESE POPS
ARE FORECAST TO SLOWLY DECREASE DURING THE NIGHT...REACHING ONLY
SLIGHT CHANCE POPS OVER THE SOUTHERN AND WESTERN ADIRONDACKS BY
SUNRISE SATURDAY. GUSTY SURFACE WINDS THIS EVENING WILL SLOWLY
DIMINISH TONIGHT...BUT AT LEAST A BREEZE SHOULD CONTINUE IN ALL OR
MOST AREAS. LOWS WILL BE IN THE 20S TO AROUND 30.
&&
.SHORT TERM /7 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
LINGERING ISOLATED SNOW SHOWERS OVER THE SOUTHERN/WESTERN
ADIRONDACKS DURING SATURDAY MORNING...THEN DRY SATURDAY AFTERNOON
THROUGH SUNDAY AS THE EFFECTS OF A LARGE HIGH PRESSURE SYSTEM
MOVING OFF THE SOUTHEASTERN STATES BEGINS TO DOMINATE THE WEATHER
OVER THE REGION. THE POSITION OF THE HIGH AS IT MOVES OFF THE COAST
WILL ALSO RESULT IN A SOUTH TO SOUTHWEST FLOW OF MILDER AIR ON
SATURDAY...AND ESPECIALLY ON SUNDAY. HIGHS SATURDAY WILL BE IN THE
MID 40S TO MID 50S...LOWS SATURDAY NIGHT IN THE MID 20S TO MID
30S....AND HIGHS SUNDAY IN THE MID 50S TO AROUND 60.
FOR SUNDAY NIGHT...A WEAK FRONT APPROACHING FROM THE WEST MAY ALLOW
FOR SHOWERS TO DEVELOP LATE SUNDAY NIGHT...AND HAVE INDICATED ABOUT
A 40 PERCENT CHANCE OF SHOWERS AFTER MIDNIGHT. CLOUDS AND SOME WIND
SHOULD KEEP TEMPS QUITE MILD...ONLY FALLING TO BETWEEN 40 AND THE
MID 40S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
THERE IS STILL SOME DISCREPANCIES AMONGST THE LONG RANGE MODELS
IN THE TIMING OF SYSTEMS. HOWEVER...THE BIG PICTURE IS SIMILAR. IT
LOOKS AS THE POSITIVE NORTH ATLANTIC OSCILLATION/NEGATIVE PACIFIC
PATTERN WILL CONTINUE. WHAT THIS MEANS IS THAT TROUGHINESS IS
FAVORED ON THE WEST COAST OF THE US WHILE RIDGING IS FAVORED ON THE
EAST COAST.
MONDAY...THE GFS HAS A WEAK STALLED OUT FRONT DEPICTED TO THE SOUTH
OF OUR REGION. AT THE SAME TIME THE ECMWF AND CMC HAVE THIS FEATURE
FURTHER NORTH. EITHER WAY...THERE APPEARS TO BE A MARGINAL THREAT
FOR SHOWERS ON MONDAY. TEMPERATURES WILL LIKELY BE IN THE 50S...TO
AROUND
60 IN THE HUDSON VALLEY ON SOUTHWARD...ABOUT 10 DEGREES ABOVE
NORMAL.
THE SAME FRONT WILL CONTINUE TO BE THE CHALLENGE INTO TUESDAY. THE
GFS SLOWLY PUSHES THE FRONT FURTHER SOUTH AND EAST. HOWEVER...THE
CMC AND ECMWF FORECAST A WAVE TO FORM ALONG IT...THEN MOVE THROUGH
LATER ON TUESDAY. WILL CONTINUE CHANCES THROUGH TUESDAY...WITH
TEMPERATURES AGAIN REACHING 55 TO AROUND 60 DEGREES. WE WILL
CONTINUE WITH CHANCES FOR RAIN SHOWERS.
BY WEDNESDAY AND THURSDAY...ALL MODELS INDICATE A COOLER AIR MASS
MOVES FROM THE NORTHWEST. H850 TEMPERATURES DROP FROM ABOUT +8C TO
WELL BELOW 0C. IT LOOKS COLD ENOUGH FOR ANOTHER LAKE RESPONSE
ALTHOUGH THE OVERALL FLOW IS SOMEWHAT ANTICYCLONIC. FOR
NOW...CONFINE ANY CHANCES OF LAKE EFFECT TO THE HIGHER TERRAIN AND
KEEP IT OUT OF THE HUDSON VALLEY ON WEDNESDAY ONLY.
TEMPERATURES LOOK TO CHILL BACK TO NORMAL LEVELS...45-50 FOR HIGHS
AND LOWS IN THE 30S.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS GENERALLY WILL PREVAIL THROUGH THE TAF PERIOD
ENDING 00Z SUNDAY. LAKE EFFECT CLOUDS AND RAIN/SNOW SHOWERS
PERSISTING AROUND KALB THIS EVENING WITH A W-NW FLOW. SOME BRIEF
MVFR CONDITIONS CAN BE EXPECTED THROUGH MUCH OF THE
EVENING...HOWEVER THE FLOW WILL BACK TO MORE OF A WEST THEN
SOUTHWEST DIRECTION...WHICH WILL CARRY ANY LAKE EFFECT SHOWERS
NORTH OF THE AREA AND WILL ALSO WEAKEN. SKIES WILL LIKELY REMAIN
BKN AT KALB/KGFL INTO THE OVERNIGHT...THEN BECOMING SCT LATE.
GENERALLY SCT CLOUDS WILL PREVAIL AT KPOU. DRY AND TRANQUIL
CONDITIONS EXPECTED ON SATURDAY WITH A SOUTHWEST FLOW DEVELOPING.
WINDS WILL SHIFT FROM THE WEST TO THE SOUTHWEST OVERNIGHT.
INITIALLY WIND SPEEDS WILL BE AROUND 10 TO 15 KT...DECREASING TO 5
TO 10 KT OVERNIGHT. WINDS ON SATURDAY WILL BE SOUTHWEST AROUND 10
KT.
OUTLOOK...
SAT-SUN...VFR. NO SIG WX.
MON...VFR. SLIGHT CHC -SHRA.
TUE...VFR. CHC -SHRA.
WED...VFR. SLIGHT CHC -SHRA.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE ANTICIPATED FOR THE NEXT 5 DAYS ON THE MAIN
STEM RIVERS.
ANY PRECIPITATION THAT WILL FALL THROUGH TONIGHT WILL BE LIGHT...
GENERALLY UNDER A TENTH OF AN INCH. SOME OF THIS WILL FALL AS SNOW
ACROSS THE HIGHER TERRAIN.
SHOWERS WILL BE POSSIBLE SUNDAY NIGHT INTO MONDAY...BUT AMOUNTS
ARE EXPECTED TO REMAIN LIGHT. ADDITIONAL THREATS FOR SHOWERS WILL
CONTINUE INTO THE MIDDLE OF NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM
NEAR TERM...GJM/JPV
SHORT TERM...GJM
LONG TERM...HWJIV
AVIATION...JPV
HYDROLOGY...GJM
AREA FORECAST DISCUSSION
NWS ALBANY NY
704 PM EST FRI NOV 11 2011
.SYNOPSIS...
A STRONG UPPER LEVEL DISTURBANCE WILL PASS TO THE EAST OF REGION
EARLY TONIGHT...AND THE RAIN OR SNOW SHOWERS OVER THE REGION WILL
GRADUALLY TAPER OFF. DRY WEATHER...AND MILDER TEMPERATURES ARE
EXPECTED FOR THE WEEKEND AS A RIDGE OF HIGH PRESSURE BUILDS INTO THE
REGION FROM THE SOUTHWEST.
&&
.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
AS OF 700 PM...SCATTERED TO NUMEROUS LAKE EFFECT RAIN/SNOW SHOWERS
CONTINUE ACROSS A CORRIDOR FROM MAINLY THE EXTREME SOUTHERN
ADIRONDACKS AND MOHAWK VALLEY SOUTHWARD THROUGH THE SCHOHARIE
VALLEY AND INTO THE EASTERN CATSKILLS. ACTIVITY HAS PRETTY MUCH
DEVELOPED INTO NARROW BANDS IN W-NW FLOW REGIME...RATHER THAN THE
CELLULAR CHARACTER OF SHOWERS BEFORE SUNSET. SOME OF THE MORE
PERSISTENT BANDS HAVE RESULTED IN ACCUMULATIONS OF 1-3
INCHES...ESPECIALLY FOR ELEVATIONS ABOVE 1000 FEET ACROSS THE
SOUTHERN HERKIMER COUNTY IN THE SAWTOOTH AS WELL AS IN PORTIONS OF
SCHOHARIE COUNTY. LOCAL HIRESWRF AND HRRR SHOWING NARROW BANDS OF
LAKE EFFECT SNOW SHOULD PERSIST THROUGH THE EVENING...ALTHOUGH THE
MIXED LAYER FLOW WILL START TO SHIFT TO MORE OF A WESTERLY
TRAJECTORY LATER THIS EVENING...THEN SOUTHWEST OVERNIGHT. THIS
WILL ALLOW BANDS TO TRANSLATE NORTHWARD SO THAT AREAS THAT ARE
EXPERIENCING ACTIVITY NOW WILL LIKELY TAPER OFF WITHIN A FEW HOURS
THIS EVENING. SO...ANY ADDITIONAL SNOW ACCUMULATIONS SHOULD BE
LIMITED TO AN INCH OR TWO AND MAINLY FOR THE AREAS PREVIOUSLY
MENTIONED. INVERSION HEIGHTS ARE EXPECTED TO LOWER OVERNIGHT...SO
ONLY A DUSTING TO A FEW TENTHS OF AN INCH CAN BE EXPECTED ACROSS
THE WESTERN ADIRONDACKS AS THE BANDS SHIFT NORTH.
PREVIOUS NEAR TERM DISCUSSION...
LAKE ENHANCED MOISTURE CONTINUES TO PRODUCE SCATTERED TO NUMEROUS
RAIN/SNOW SHOWERS ACROSS THE REGION...ESPECIALLY ACROSS HIGHER
TERRAIN. NO WELL DEFINED BAND AS OF 400 PM...BUT ACTIVITY APPEARS
MORE CELLULAR. WOULD EXPECT A BETTER DEFINED BAND WILL DEVELOP THIS
EVENING AS DAYTIME HEATING WANES. THIS BAND WOULD ALSO BE SHIFTING
STEADILY NORTH DURING THE NIGHT AND WEAKENING AS THE INVERSION
BEGINS TO LOWER. LIKELY POPS OVER THE WESTERN MOHAWK VALLEY AND
SCHOHARIE VALLEY TO START THE EVENING...WITH CHANCE TO SLIGHT CHANCE
POPS ELSEWHERE. THESE POPS ARE FORECAST TO SLOWLY DECREASE DURING
THE NIGHT...REACHING ONLY SLIGHT CHANCE POPS OVER THE SOUTHERN AND
WESTERN ADIRONDACKS BY SUNRISE SATURDAY. GUSTY SURFACE WINDS THIS
EVENING WILL SLOWLY DIMINISH TONIGHT...BUT AT LEAST A BREEZE SHOULD
CONTINUE IN ALL OR MOST AREAS. LOWS WILL BE IN THE 20S TO AROUND 30.
&&
.SHORT TERM /7 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
LINGERING ISOLATED SNOW SHOWERS OVER THE SOUTHERN/WESTERN
ADIRONDACKS DURING SATURDAY MORNING...THEN DRY SATURDAY AFTERNOON
THROUGH SUNDAY AS THE EFFECTS OF A LARGE HIGH PRESSURE SYSTEM
MOVING OFF THE SOUTHEASTERN STATES BEGINS TO DOMINATE THE WEATHER
OVER THE REGION. THE POSITION OF THE HIGH AS IT MOVES OFF THE COAST
WILL ALSO RESULT IN A SOUTH TO SOUTHWEST FLOW OF MILDER AIR ON
SATURDAY...AND ESPECIALLY ON SUNDAY. HIGHS SATURDAY WILL BE IN THE
MID 40S TO MID 50S...LOWS SATURDAY NIGHT IN THE MID 20S TO MID
30S....AND HIGHS SUNDAY IN THE MID 50S TO AROUND 60.
FOR SUNDAY NIGHT...A WEAK FRONT APPROACHING FROM THE WEST MAY ALLOW
FOR SHOWERS TO DEVELOP LATE SUNDAY NIGHT...AND HAVE INDICATED ABOUT
A 40 PERCENT CHANCE OF SHOWERS AFTER MIDNIGHT. CLOUDS AND SOME WIND
SHOULD KEEP TEMPS QUITE MILD...ONLY FALLING TO BETWEEN 40 AND THE
MID 40S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
THERE IS STILL SOME DISCREPANCIES AMONGST THE LONG RANGE MODELS
IN THE TIMING OF SYSTEMS. HOWEVER...THE BIG PICTURE IS SIMILAR. IT
LOOKS AS THE POSITIVE NORTH ATLANTIC OSCILLATION/NEGATIVE PACIFIC
PATTERN WILL CONTINUE. WHAT THIS MEANS IS THAT TROUGHINESS IS
FAVORED ON THE WEST COAST OF THE US WHILE RIDGING IS FAVORED ON THE
EAST COAST.
MONDAY...THE GFS HAS A WEAK STALLED OUT FRONT DEPICTED TO THE SOUTH
OF OUR REGION. AT THE SAME TIME THE ECMWF AND CMC HAVE THIS FEATURE
FURTHER NORTH. EITHER WAY...THERE APPEARS TO BE A MARGINAL THREAT
FOR SHOWERS ON MONDAY. TEMPERATURES WILL LIKELY BE IN THE 50S...TO
AROUND
60 IN THE HUDSON VALLEY ON SOUTHWARD...ABOUT 10 DEGREES ABOVE
NORMAL.
THE SAME FRONT WILL CONTINUE TO BE THE CHALLENGE INTO TUESDAY. THE
GFS SLOWLY PUSHES THE FRONT FURTHER SOUTH AND EAST. HOWEVER...THE
CMC AND ECMWF FORECAST A WAVE TO FORM ALONG IT...THEN MOVE THROUGH
LATER ON TUESDAY. WILL CONTINUE CHANCES THROUGH TUESDAY...WITH
TEMPERATURES AGAIN REACHING 55 TO AROUND 60 DEGREES. WE WILL
CONTINUE WITH CHANCES FOR RAIN SHOWERS.
BY WEDNESDAY AND THURSDAY...ALL MODELS INDICATE A COOLER AIR MASS
MOVES FROM THE NORTHWEST. H850 TEMPERATURES DROP FROM ABOUT +8C TO
WELL BELOW 0C. IT LOOKS COLD ENOUGH FOR ANOTHER LAKE RESPONSE
ALTHOUGH THE OVERALL FLOW IS SOMEWHAT ANTICYCLONIC. FOR
NOW...CONFINE ANY CHANCES OF LAKE EFFECT TO THE HIGHER TERRAIN AND
KEEP IT OUT OF THE HUDSON VALLEY ON WEDNESDAY ONLY.
TEMPERATURES LOOK TO CHILL BACK TO NORMAL LEVELS...45-50 FOR HIGHS
AND LOWS IN THE 30S.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS GENERALLY WILL PREVAIL THROUGH THE TAF PERIOD
ENDING 00Z SUNDAY. LAKE EFFECT CLOUDS AND RAIN/SNOW SHOWERS
PERSISTING AROUND KALB THIS EVENING WITH A W-NW FLOW. SOME BRIEF
MVFR CONDITIONS CAN BE EXPECTED THROUGH MUCH OF THE
EVENING...HOWEVER THE FLOW WILL BACK TO MORE OF A WEST THEN
SOUTHWEST DIRECTION...WHICH WILL CARRY ANY LAKE EFFECT SHOWERS
NORTH OF THE AREA AND WILL ALSO WEAKEN. SKIES WILL LIKELY REMAIN
BKN AT KALB/KGFL INTO THE OVERNIGHT...THEN BECOMING SCT LATE.
GENERALLY SCT CLOUDS WILL PREVAIL AT KPOU. DRY AND TRANQUIL
CONDITIONS EXPECTED ON SATURDAY WITH A SOUTHWEST FLOW DEVELOPING.
WINDS WILL SHIFT FROM THE WEST TO THE SOUTHWEST OVERNIGHT.
INITIALLY WIND SPEEDS WILL BE AROUND 10 TO 15 KT...DECREASING TO 5
TO 10 KT OVERNIGHT. WINDS ON SATURDAY WILL BE SOUTHWEST AROUND 10
KT.
OUTLOOK...
SAT-SUN...VFR. NO SIG WX.
MON...VFR. SLIGHT CHC -SHRA.
TUE...VFR. CHC -SHRA.
WED...VFR. SLIGHT CHC -SHRA.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE ANTICIPATED FOR THE NEXT 5 DAYS ON THE MAIN
STEM RIVERS.
ANY PRECIPITATION THAT WILL FALL THROUGH TONIGHT WILL BE LIGHT...
GENERALLY UNDER A TENTH OF AN INCH. SOME OF THIS WILL FALL AS SNOW
ACROSS THE HIGHER TERRAIN.
SHOWERS WILL BE POSSIBLE SUNDAY NIGHT INTO MONDAY...BUT AMOUNTS
ARE EXPECTED TO REMAIN LIGHT. ADDITIONAL THREATS FOR SHOWERS WILL
CONTINUE INTO THE MIDDLE OF NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...GJM
NEAR TERM...GJM/JPV
SHORT TERM...GJM
LONG TERM...HWJIV
AVIATION...JPV
HYDROLOGY...GJM
AREA FORECAST DISCUSSION
NWS ALBANY NY
1254 AM EST FRI NOV 11 2011
.SYNOPSIS...
A COLD FRONT WILL SLOWLY MOVE TO OUR EAST TONIGHT. A DISTURBANCE
TO OUR EAST WILL WRAP SOME MOISTURE BACK ACROSS OUR
REGION...MAINLY EAST OF THE HUDSON VALLEY. HOWEVER...SOME LAKE
EFFECT MOISTURE WILL ALSO BRING SHOWERS OF RAIN AND SNOW...MAINLY
TO THE NORTHWEST OF ALBANY. A BRISK WESTERLY FLOW WILL CONTINUE
ON FRIDAY WITH MORE LAKE EFFECT RAIN AND SNOW SHOWERS MAINLY
ACROSS WESTERN AREAS.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1255 AM EST...THE BAND OF MAINLY LIGHT RAIN SHOWERS IS NOW
MOVING JUST E OF HUDSON RIVER...EXTENDING INTO WESTERN NEW
ENGLAND. THIS SHOULD CONTINUE MOVING E OVER THE NEXT 1-3
HOURS...WITH LITTLE IF ANY ADDITIONAL RAIN EXPECTED WEST OF THE
HUDSON RIVER THROUGH 4 OR 5 AM...EXCLUDING THE WESTERN
ADIRONDACKS/MOHAWK VALLEY...WHERE SOME DEVELOPING LAKE EFFECT
RAIN/SNOW SHOWERS MAY REACH. THESE LAKE EFFECT/ENHANCED SHOWERS
SHOULD THEN EXPAND FURTHER S/E TOWARD DAYBREAK.
HAVE ALSO LOWERED MINS A BIT...AS CURRENT TEMPS ALREADY NEARING
PREVIOUSLY INDICATED MINS.
OTHERWISE...JUST MINOR TWEAKS TO HOURLY TEMPS/DEWPOINTS BASED ON
RECENT OBS.
PREVIOUS DISCUSSIONS FOLLOW...
AS OF 1000 PM...BAND OF SHOWERS FINALLY MOVED EASTWARD INTO THE
HUDSON VALLEY BUT HAS ALSO BROKEN APART IN THE PROCESS. DRIER PUSH
OF AIR RAPIDLY MOVING THROUGH THE MOHAWK VALLEY AND WESTERN
ADIRONDACKS. WILL MENTION RELATIVELY HIGHER POPS FROM THE HUDSON
VALLEY EASTWARD FROM LATE THIS EVENING INTO THE EVENING HOURS
BEFORE TAPERING OFF DURING THE LATTER HALF OF THE OVERNIGHT. TEMPS
ARE ON TRACK...WITH SOME OF THE HIGHER TERRAIN SEEING SNOW SHOWERS
MIX IN WITH RAIN BUT PRECIP WILL CONTINUE TO BE LIGHT. SOME LAKE
EFFECT RESPONSE WILL BE POSSIBLE OFF ONTARIO AS COLDER AIR
CONTINUES TO FILTER IN AT THE SURFACE AND ALOFT...COOLING ENOUGH
FOR CONDITIONAL INSTABILITY TO DEVELOP WITH SCATTERED RAIN/SNOW
SHOWERS DEVELOPING IN THE WESTERN ADIRONDACKS/WESTERN MOHAWK
VALLEY CORRIDOR TOWARDS MORNING.
PREVIOUS NEAR TERM DISCUSSIONS...
AS OF 700 PM...BATCH OF RAIN TO THE EAST HAS EXITED INTO CENTRAL
AND EASTERN NEW ENGLAND...WHILE THE NARROW BUT PERSISTENT BAND OF
SHOWERS TO THE WEST OF ALBANY SLOWLY ADVANCES EASTWARD. WILL
MENTION DRY CONDITIONS FOR THE NEXT FEW HOURS ACROSS WESTERN NEW
ENGLAND...WITH POPS GRADUALLY INCREASING WESTWARD FROM TACONICS TO
THE HUDSON VALLEY. HIGHEST POPS EARLY THIS EVENING WILL REMAIN
OVER THE SOUTHERN ADIRONDACKS...THE MOHAWK AND SCHOHARIE
VALLEYS...AND THE EASTERN CATSKILLS. WHERE MEASURABLE RAINFALL
DOES OCCUR...AMOUNTS WILL BE LIGHT. THE SLOW EASTWARD PROGRESSION
IS DUE TO THE UPPER LEVEL TROF AXIS LAGGING WELL BACK TO THE WEST
ACROSS THE CENTRAL GREAT LAKES.
AS OF 430 PM...DOPPLER RADAR INDICATES TWO AREAS OF RAIN. THE FIRST
ONE TO OUR EAST IS TIED IN TO AN INVERTED TROUGH/DEVELOPING LOW
PRESSURE SPAWNED BY WEAKENING TROPICAL STORM SHAWN TO THE SOUTHEAST
OF CAPE COD. IT LOOKS AS IF ALL THIS MOISTURE WILL NOT ONLY STAY OFF
TO THE EAST OF MOST OF COUNTY WARNING AREA (EXCEPT PERHAPS EASTERN
WINDHAM WERE SHOWERS HAVE MOVED IN)...BUT INITIALLY AS THIS SYSTEM
DEVELOPS...WILL CONTINUE TO INDUCE WEAK SUBSIDENCE OVER THE HUDSON
VALLEY.
THEN TO THE WEST...WAS A LINE OF SHOWERS ASSOCIATED WITH UPWARD
MOTION...OVER THE MOHAWK VALLEY AND JUST INTO THE CATSKILLS...MAINLY
TIED IN THE RR ENTRANCE REGION OF A STRONG UPPER LEVEL JET OVER
125KTS AT THE H250 MB LEVEL. THIS LINE HAS BEEN VERY SLOW TO MOVE
EAST. HOWEVER...AS LOW PRESSURE DEEPENS AND MOVE TO THE GULF OF
MAINE...THE SUBSIDENCE SHOULD WEAKEN LATER THIS EVENING. THIS
WOULD ALLOW THIS LINE TO WORK EAST AND PRODUCE SCATTERED SHOWERS
ACROSS THE REMAINDER OF THE REGION. RAINFALL AMOUNTS WITH THESE
SHOWERS WILL BE LIGHT...GENERALLY UNDER A TENTH OF AN INCH...EXCEPT
A LITTLE HIGHER ACROSS THE MOHAWK VALLEY...MAYBE CLOSER TO A QUARTER
OF AN INCH.
THEN...AS THE STORM CONTINUES TO DEEPEN AND RACE OFF INTO THE
CANADIAN MARITIMES...THE FLOW WILL BECOME NORTHWESTERLY. H850 TEMPS
LOOK TO DROP TO AROUND -5C AND THIS WILL BE COLD ENOUGH TO TRIGGER A
RESPONSE OF LAKE ONTARIO WHERE WATER TEMPS ARE STILL CLOSE TO 50
DEGREES. HOWEVER INITIALLY THERE WILL BE A GOOD AMOUNT OF SHEAR SO
THE REAL LAKE EFFECT WILL LIKELY NOT HAPPEN UNTIL LATER FRIDAY.
OVERNIGHT LOWS WILL FALL BACK INTO THE 30S ACROSS MOST IF NOT ALL OF
THE COUNTY WARNING AREA. A BREEZE WILL PERSIST OUT OF THEN NORTHWEST
5 TO 15 MPH...WITH SOME GUSTS TO 25 MPH.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH SATURDAY NIGHT/...
FRIDAY/S WEATHER WILL FEATURE VERY TYPICAL MID NOVEMBER CONDITIONS
AS IT WILL BE BRISK WITH GENERALLY MORE CLOUDS THAN SUNSHINE AND
NUISANCE TYPE SHOWERS OR RAIN (OR SNOW IN THE HIGHER TERRAIN).
A STRONG...NEGATIVELY TILTING UPPER LEVEL TROUGH WILL MOVE ACROSS
DURING THE MORNING/EARLY AFTERNOON HOURS. THE MID LEVEL COLD POOL
ASSOCIATED WITH THIS FEATURE REMAINS IMPRESSIVE...WITH -30C AT 500
MB. THIS WILL PROMOTE ENOUGH INSTABILITY...IN COMBINATION WITH
INCREASING LAKE MOISTURE TO ALLOW FOR ISOLATED TO SCATTERED
RAIN/SNOW SHOWERS IN VALLEYS...WITH SCATTERED TO NUMEROUS...MAINLY
SNOW SHOWERS ACROSS HIGHER ELEVATIONS FROM MID MORNING INTO THE
AFTERNOON HOURS. THE SHOWERS MAY CONGEAL INTO MORE LAKE
EFFECT/ENHANCED BANDS DURING THE MID TO LATE AFTERNOON HOURS AFTER A
MORE CELLULAR NATURE DURING THE DAY WITH THE PASSAGE OF THE UPPER
LEVEL TROUGH. THE LOW LEVEL FLOW WOULD FAVOR ANY LATE DAY BANDS TO
OCCUR MAINLY ACROSS EXTREME SW HERKIMER CO...POSSIBLY INTO SCHOHARIE
CO AND THE EASTERN CATSKILLS...WHERE SOME VERY MINOR ACCUMS OF
SNOWFALL COULD OCCUR...PERHAPS LOCALLY UP TO 2 INCHES.
THE LATEST NAM GUIDANCE INDICATES THAT THE WIND WIND WILL NOT GET
QUITE AS STRONG AS EARLIER AS THE STORM MIGHT BECOME QUITE AS DEEP
AND MOVE FASTER. HOWEVER...BUT IT WILL BE GUSTY BY AFTERNOON...WITH
ISOLATED GUSTS UP TO 35-40 MPH ACROSS PORTIONS OF THE MOHAWK VALLEY
AND HIGHER TERRAIN...25-30 MOST OTHER PLACES. TEMPERATURES WILL TOP
AROUND 50 IN THE MID HUDSON VALLEY....UPPER 40S CAPITAL DISTRICT.
ACROSS THE HIGHER TERRAIN HIGHS WILL ONLY REACH 35-40 ACROSS THE
HIGHER TERRAIN OF THE DACKS AND SOUTHERN GREENS.
FRIDAY NIGHT...SOME LAKE EFFECT BANDS OF RAIN/SNOW MAY BE
ONGOING ACROSS THE WESTERN MOHAWK VALLEY...SCHOHARIE VALLEY AND
POSSIBLY INTO THE CAPITAL REGION EARLY. HOWEVER...WITH THE
APPROACH OF ANOTHER SHORTWAVE LATE AT NIGHT...THE LOW LEVEL FLOW
SHOULD BEGIN BACKING...ALLOWING ANY BANDS TO SHIFT NORTH INTO THE
WESTERN ADIRONDACKS. SOME ACCUMS WILL BE POSSIBLE IN THESE
AREAS...PERHAPS ON THE ORDER OF 1-3 INCHES ACROSS THE
ADIRONDACKS...AND LITTLE OF ANY ACCUMULATIONS ELSEWHERE. ANY SNOW
SHOWERS SHOULD GRADUALLY TAPER OFF AFTER MIDNIGHT...ALTHOUGH CLOUDS
MAY LINGER AS MOISTURE REMAINS TRAPPED BENEATH LOWERING INVERSION.
WILL THEREFORE CONTINUE SLIGHTLY ABOVE MOS GUIDANCE FOR MINS...WITH
LOWER 30S ACROSS THE UPPER HUDSON RIVER VALLEYS...AND GENERALLY 20S
ELSEWHERE.
ON SATURDAY...SOME LINGERING SNOW SHOWERS MAY PERSIST SATURDAY
MORNING ACROSS NORTHERN HERKIMER/HAMILTON COUNTIES. OTHERWISE...WE
STILL EXPECT CLOUDS TO GRADUALLY LIFT OUT OF THE REGION BY SATURDAY
AFTERNOON. TEMPERATURES WILL TOP OUT 50-55 IN THE HUDSON VALLEY FROM
ALBANY SOUTHWARD...40S ELSEWHERE.
BY SATURDAY NIGHT THERE STILL MIGHT BE A LAKE EFFECT CLOUDS AROUND
BUT OVERALL IT LOOKS MOSTLY CLEAR. FORECASTING LOW TEMPERATURES WILL
BE A CHALLENGE THAT NIGHT. SURFACE HIGH PRESSURE WILL BE CRESTING
WELL TO OUR SOUTH AND A SOUTHERLY FLOW WILL BEGIN TO DEVELOP...AT
LEAST ALOFT. THE QUESTION IS HOW QUICKLY THE FLOW BEGINS THE WARM
AIR PROCESSES NEAR THE SURFACE. IT MIGHT TAKE A WHILE BUT THE FLOW
WILL ACTUALLY BEGIN BY LATE SATURDAY. FOR NOW...WENT CLOSE THE
MAV/MET GUIDANCE EXCEPT A LITTLE LOWER IN THE USUAL
PLACES...SHELTERED MOUNTAIN VALLEYS.
SUNDAY STILL LOOKS THE BEST PORTION OF THE HOLIDAY WEEKEND. IT WILL
BE A BIT BREEZE WITH A SSW WIND BUT THAT WIND SHOULD MILDER AIR INTO
THE REGION WITH TEMPERATURES CRESTING WELL INTO THE 50S EVERYWHERE
BY AFTERNOON...EVEN WITH LIMITED SUNSHINE.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THERE CONTINUES TO BE SOME TIMING DIFFERENCES WITH FRONTAL PASSAGES
IN THE LONG TERM...AND HOW AMPLIFIED THE MEAN LONGWAVE TROUGH
BECOMES IN THE MID WEEK. THE GFS AND HPC TRENDS ARE FOR A FLATTER
AND BROADER UPPER LEVEL TROUGH WITH SEVERAL SHORTWAVES/FRONTAL
PASSAGE IN THE FLAT/BROAD CYCLONIC FLOW IN THE EARLY TO MID WEEK.
WE ARE LEANING THIS WAY WITH THE FORECAST.
SUNDAY NIGHT INTO MONDAY...THE GFS AND HPC GUIDANCE BOTH HAVE A COLD
FRONT APPROACHING FROM THE ERN GREAT LAKES REGION...OHIO AND MS
VALLEYS. WE GRADUALLY INCREASED THE POPS TO CHC VALUES BY MONDAY.
THE ECMWF IS SLOWER WITH THE FRONT WITH SOME RIDGING INCREASING
ALONG THE EAST COAST. THE LATEST GFS INDICATES SOME COLD AIR
ADVECTION DURING THE DAY ON MONDAY WITH TEMPS FALLING TO +1 TO +5C
FROM NW TO SE OVER THE FCST AREA. LOWS WILL BE MILD MONDAY
MORNING...MAINLY IN THE 40S...AND HIGHS AHEAD OF THE FRONTAL PASSAGE
RANGE FROM THE U50S TO L60S IN THE VALLEYS...AND U40S TO M50S OVER
THE HILLS AND MTNS.
MONDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE BRIEFLY BUILDS IN MONDAY
NIGHT INTO TUESDAY IN THE RELATIVELY FLAT MID LEVEL FLOW. A WAVE
MOVES ALONG THE OLD COLD FRONTAL BOUNDARY WHICH IS STATIONARY OVER
THE MID ATLANTIC REGION. THE CHANCES FOR SHOWERS LOOK TO INCREASE
AGAIN...WITH OVER RUNNING PCPN AHEAD OF THE WAVE LATE TUE-TUE
NIGHT. A NORTHERN STREAM DISTURBANCE APPROACHES FROM THE GREAT
LAKES REGION TOWARDS WEDNESDAY WITH ANOTHER BATCH OF SHOWERS...AND
ANOTHER SHOT OF COLD ADVECTION. ONCE THIS FRONT MOVES THROUGH THE
UPPER LEVEL TROUGH AMPLIFIES WITH NW FLOW DOMINATING ALOFT...AND
HIGH PRESSURE BUILDING IN FROM THE CNTRL PLAINS. TEMPS LOOK TO
AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL DURING THIS TIME FRAME.
WEDNESDAY NIGHT INTO THURSDAY...OVERALL LOOKS COLDER AND DRY WITH
PERHAPS SOME LAKE EFFECT OR UPSLOPE RAIN/SNOW SHOWERS NORTH AND WEST
OF THE CAPITAL REGION. H850 TEMPS FINISH THE EXTENDED IN THE 0 TO
-7C RANGE FROM NW TO SE OVER THE FCST AREA...WITH TEMPS FALLING TO
NORMAL OR BELOW NORMAL LEVELS. HIGHS ON THU WILL STRUGGLE TO GET OUT
OF THE 40S.
THIS IS A LOW CONFIDENCE FORECAST...AND WE WILL SEE IF THERE IS
BETTER AGREEMENT IN THE MEDIUM RANGE GUIDANCE OVER THE NEXT FEW
CYCLES.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
COLD FRONT HAS MOVED WELL EAST OF THE KGFL/KALB/KPOU
TERMINALS...WHILE A NARROW BATCH OF SHOWERS LAGS BEHIND THE FRONT
DUE TO THE UPPER LEVEL TROF REMAINING FARTHER BACK TO THE WEST
OVER THE GREAT LAKES. VFR CONDITIONS WILL PERSIST THROUGH THE
EARLY MORNING HOURS WITH SCATTERED SHOWERS DURING THIS TIME.
SHOWERS SHOULD GENERALLY MOVE EAST OF THE HUDSON VALLEY BY SUNRISE
OR A LITTLE AFTER. ACTIVITY SCATTERED ENOUGH AND LIGHT ENOUGH THAT
PUTTING VCSH INSTEAD OF PUTTING PERIOD OF MVFR CONDITIONS.
WINDS WILL BE NORTHWEST AROUND 5-10 KT THROUGH THE EARLY MORNING
HOURS...BECOMING WEST-NORTHWEST LATER IN THE MORNING AROUND 12-20
KT WITH GUST OF 25-30 KT POSSIBLE ESPECIALLY NEAR KALB WHERE WIND
SPEEDS WILL BE ENHANCED DOWN THE MOHAWK VALLEY. WINDS WILL
DIMINISH THIS EVENING.
OUTLOOK...
FRI NIGHT...VFR/MVFR. ISOLD -SHRASN.
SAT-SUN...VFR. NO SIG WX.
MON...VFR. SLIGHT CHC -SHRA.
TUE...VFR. CHC -SHRA.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE ANTICIPATED THE NEXT 5 DAYS ON THE MAIN STEM
RIVERS.
ANY PRECIPITATION THAT WILL FALL TONIGHT THROUGH FRIDAY NIGHT WILL
BE LIGHT...GENERALLY UNDER A QUARTER OF AN INCH OR LESS. SOME OF
THIS COULD FALL AS SNOW ACROSS THE HIGHER TERRAIN WITH ONLY
LOCALIZED MINOR ACCUMULATIONS.
THE NEXT THREAT OF PRECIPITATION WOULD BE MONDAY INTO TUESDAY BUT
AGAIN FROM THIS VANTAGE POINT...AMOUNTS OF PRECIPITATION (FALLING AS
RAIN) LOOK LIGHT.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV/HWJIV
NEAR TERM...KL/JPV/HWJIV
SHORT TERM...HWJIV
LONG TERM...WASULA
AVIATION...NAS
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
1222 AM EST FRI NOV 11 2011
.SYNOPSIS...
A COLD FRONT WILL SLOWLY MOVE TO OUR EAST TONIGHT. A DISTURBANCE
TO OUR EAST WILL WRAP SOME MOISTURE BACK ACROSS OUR
REGION...MAINLY EAST OF THE HUDSON VALLEY. HOWEVER...SOME LAKE
EFFECT MOISTURE WILL ALSO BRING SHOWERS OF RAIN AND SNOW...MAINLY
TO THE NORTHWEST OF ALBANY. A BRISK WESTERLY FLOW WILL CONTINUE
ON FRIDAY WITH MORE LAKE EFFECT RAIN AND SNOW SHOWERS MAINLY
ACROSS WESTERN AREAS.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1000 PM...BAND OF SHOWERS FINALLY MOVED EASTWARD INTO THE
HUDSON VALLEY BUT HAS ALSO BROKEN APART IN THE PROCESS. DRIER PUSH
OF AIR RAPIDLY MOVING THROUGH THE MOHAWK VALLEY AND WESTERN
ADIRONDACKS. WILL MENTION RELATIVELY HIGHER POPS FROM THE HUDSON
VALLEY EASTWARD FROM LATE THIS EVENING INTO THE EVENING HOURS
BEFORE TAPERING OFF DURING THE LATTER HALF OF THE OVERNIGHT. TEMPS
ARE ON TRACK...WITH SOME OF THE HIGHER TERRAIN SEEING SNOW SHOWERS
MIX IN WITH RAIN BUT PRECIP WILL CONTINUE TO BE LIGHT. SOME LAKE
EFFECT RESPONSE WILL BE POSSIBLE OFF ONTARIO AS COLDER AIR
CONTINUES TO FILTER IN AT THE SURFACE AND ALOFT...COOLING ENOUGH
FOR CONDITIONAL INSTABILITY TO DEVELOP WITH SCATTERED RAIN/SNOW
SHOWERS DEVELOPING IN THE WESTERN ADIRONDACKS/WESTERN MOHAWK
VALLEY CORRIDOR TOWARDS MORNING.
PREVIOUS NEAR TERM DISCUSSIONS...
AS OF 700 PM...BATCH OF RAIN TO THE EAST HAS EXITED INTO CENTRAL
AND EASTERN NEW ENGLAND...WHILE THE NARROW BUT PERSISTENT BAND OF
SHOWERS TO THE WEST OF ALBANY SLOWLY ADVANCES EASTWARD. WILL
MENTION DRY CONDITIONS FOR THE NEXT FEW HOURS ACROSS WESTERN NEW
ENGLAND...WITH POPS GRADUALLY INCREASING WESTWARD FROM TACONICS TO
THE HUDSON VALLEY. HIGHEST POPS EARLY THIS EVENING WILL REMAIN
OVER THE SOUTHERN ADIRONDACKS...THE MOHAWK AND SCHOHARIE
VALLEYS...AND THE EASTERN CATSKILLS. WHERE MEASURABLE RAINFALL
DOES OCCUR...AMOUNTS WILL BE LIGHT. THE SLOW EASTWARD PROGRESSION
IS DUE TO THE UPPER LEVEL TROF AXIS LAGGING WELL BACK TO THE WEST
ACROSS THE CENTRAL GREAT LAKES.
AS OF 430 PM...DOPPLER RADAR INDICATES TWO AREAS OF RAIN. THE FIRST
ONE TO OUR EAST IS TIED IN TO AN INVERTED TROUGH/DEVELOPING LOW
PRESSURE SPAWNED BY WEAKENING TROPICAL STORM SHAWN TO THE SOUTHEAST
OF CAPE COD. IT LOOKS AS IF ALL THIS MOISTURE WILL NOT ONLY STAY OFF
TO THE EAST OF MOST OF COUNTY WARNING AREA (EXCEPT PERHAPS EASTERN
WINDHAM WERE SHOWERS HAVE MOVED IN)...BUT INITIALLY AS THIS SYSTEM
DEVELOPS...WILL CONTINUE TO INDUCE WEAK SUBSIDENCE OVER THE HUDSON
VALLEY.
THEN TO THE WEST...WAS A LINE OF SHOWERS ASSOCIATED WITH UPWARD
MOTION...OVER THE MOHAWK VALLEY AND JUST INTO THE CATSKILLS...MAINLY
TIED IN THE RR ENTRANCE REGION OF A STRONG UPPER LEVEL JET OVER
125KTS AT THE H250 MB LEVEL. THIS LINE HAS BEEN VERY SLOW TO MOVE
EAST. HOWEVER...AS LOW PRESSURE DEEPENS AND MOVE TO THE GULF OF
MAINE...THE SUBSIDENCE SHOULD WEAKEN LATER THIS EVENING. THIS
WOULD ALLOW THIS LINE TO WORK EAST AND PRODUCE SCATTERED SHOWERS
ACROSS THE REMAINDER OF THE REGION. RAINFALL AMOUNTS WITH THESE
SHOWERS WILL BE LIGHT...GENERALLY UNDER A TENTH OF AN INCH...EXCEPT
A LITTLE HIGHER ACROSS THE MOHAWK VALLEY...MAYBE CLOSER TO A QUARTER
OF AN INCH.
THEN...AS THE STORM CONTINUES TO DEEPEN AND RACE OFF INTO THE
CANADIAN MARITIMES...THE FLOW WILL BECOME NORTHWESTERLY. H850 TEMPS
LOOK TO DROP TO AROUND -5C AND THIS WILL BE COLD ENOUGH TO TRIGGER A
RESPONSE OF LAKE ONTARIO WHERE WATER TEMPS ARE STILL CLOSE TO 50
DEGREES. HOWEVER INITIALLY THERE WILL BE A GOOD AMOUNT OF SHEAR SO
THE REAL LAKE EFFECT WILL LIKELY NOT HAPPEN UNTIL LATER FRIDAY.
OVERNIGHT LOWS WILL FALL BACK INTO THE 30S ACROSS MOST IF NOT ALL OF
THE COUNTY WARNING AREA. A BREEZE WILL PERSIST OUT OF THEN NORTHWEST
5 TO 15 MPH...WITH SOME GUSTS TO 25 MPH.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH SATURDAY NIGHT/...
FRIDAY/S WEATHER WILL FEATURE VERY TYPICAL MID NOVEMBER CONDITIONS
AS IT WILL BE BRISK WITH GENERALLY MORE CLOUDS THAN SUNSHINE AND
NUISANCE TYPE SHOWERS OR RAIN (OR SNOW IN THE HIGHER TERRAIN).
A STRONG...NEGATIVELY TILTING UPPER LEVEL TROUGH WILL MOVE ACROSS
DURING THE MORNING/EARLY AFTERNOON HOURS. THE MID LEVEL COLD POOL
ASSOCIATED WITH THIS FEATURE REMAINS IMPRESSIVE...WITH -30C AT 500
MB. THIS WILL PROMOTE ENOUGH INSTABILITY...IN COMBINATION WITH
INCREASING LAKE MOISTURE TO ALLOW FOR ISOLATED TO SCATTERED
RAIN/SNOW SHOWERS IN VALLEYS...WITH SCATTERED TO NUMEROUS...MAINLY
SNOW SHOWERS ACROSS HIGHER ELEVATIONS FROM MID MORNING INTO THE
AFTERNOON HOURS. THE SHOWERS MAY CONGEAL INTO MORE LAKE
EFFECT/ENHANCED BANDS DURING THE MID TO LATE AFTERNOON HOURS AFTER A
MORE CELLULAR NATURE DURING THE DAY WITH THE PASSAGE OF THE UPPER
LEVEL TROUGH. THE LOW LEVEL FLOW WOULD FAVOR ANY LATE DAY BANDS TO
OCCUR MAINLY ACROSS EXTREME SW HERKIMER CO...POSSIBLY INTO SCHOHARIE
CO AND THE EASTERN CATSKILLS...WHERE SOME VERY MINOR ACCUMS OF
SNOWFALL COULD OCCUR...PERHAPS LOCALLY UP TO 2 INCHES.
THE LATEST NAM GUIDANCE INDICATES THAT THE WIND WIND WILL NOT GET
QUITE AS STRONG AS EARLIER AS THE STORM MIGHT BECOME QUITE AS DEEP
AND MOVE FASTER. HOWEVER...BUT IT WILL BE GUSTY BY AFTERNOON...WITH
ISOLATED GUSTS UP TO 35-40 MPH ACROSS PORTIONS OF THE MOHAWK VALLEY
AND HIGHER TERRAIN...25-30 MOST OTHER PLACES. TEMPERATURES WILL TOP
AROUND 50 IN THE MID HUDSON VALLEY....UPPER 40S CAPITAL DISTRICT.
ACROSS THE HIGHER TERRAIN HIGHS WILL ONLY REACH 35-40 ACROSS THE
HIGHER TERRAIN OF THE DACKS AND SOUTHERN GREENS.
FRIDAY NIGHT...SOME LAKE EFFECT BANDS OF RAIN/SNOW MAY BE
ONGOING ACROSS THE WESTERN MOHAWK VALLEY...SCHOHARIE VALLEY AND
POSSIBLY INTO THE CAPITAL REGION EARLY. HOWEVER...WITH THE
APPROACH OF ANOTHER SHORTWAVE LATE AT NIGHT...THE LOW LEVEL FLOW
SHOULD BEGIN BACKING...ALLOWING ANY BANDS TO SHIFT NORTH INTO THE
WESTERN ADIRONDACKS. SOME ACCUMS WILL BE POSSIBLE IN THESE
AREAS...PERHAPS ON THE ORDER OF 1-3 INCHES ACROSS THE
ADIRONDACKS...AND LITTLE OF ANY ACCUMULATIONS ELSEWHERE. ANY SNOW
SHOWERS SHOULD GRADUALLY TAPER OFF AFTER MIDNIGHT...ALTHOUGH CLOUDS
MAY LINGER AS MOISTURE REMAINS TRAPPED BENEATH LOWERING INVERSION.
WILL THEREFORE CONTINUE SLIGHTLY ABOVE MOS GUIDANCE FOR MINS...WITH
LOWER 30S ACROSS THE UPPER HUDSON RIVER VALLEYS...AND GENERALLY 20S
ELSEWHERE.
ON SATURDAY...SOME LINGERING SNOW SHOWERS MAY PERSIST SATURDAY
MORNING ACROSS NORTHERN HERKIMER/HAMILTON COUNTIES. OTHERWISE...WE
STILL EXPECT CLOUDS TO GRADUALLY LIFT OUT OF THE REGION BY SATURDAY
AFTERNOON. TEMPERATURES WILL TOP OUT 50-55 IN THE HUDSON VALLEY FROM
ALBANY SOUTHWARD...40S ELSEWHERE.
BY SATURDAY NIGHT THERE STILL MIGHT BE A LAKE EFFECT CLOUDS AROUND
BUT OVERALL IT LOOKS MOSTLY CLEAR. FORECASTING LOW TEMPERATURES WILL
BE A CHALLENGE THAT NIGHT. SURFACE HIGH PRESSURE WILL BE CRESTING
WELL TO OUR SOUTH AND A SOUTHERLY FLOW WILL BEGIN TO DEVELOP...AT
LEAST ALOFT. THE QUESTION IS HOW QUICKLY THE FLOW BEGINS THE WARM
AIR PROCESSES NEAR THE SURFACE. IT MIGHT TAKE A WHILE BUT THE FLOW
WILL ACTUALLY BEGIN BY LATE SATURDAY. FOR NOW...WENT CLOSE THE
MAV/MET GUIDANCE EXCEPT A LITTLE LOWER IN THE USUAL
PLACES...SHELTERED MOUNTAIN VALLEYS.
SUNDAY STILL LOOKS THE BEST PORTION OF THE HOLIDAY WEEKEND. IT WILL
BE A BIT BREEZE WITH A SSW WIND BUT THAT WIND SHOULD MILDER AIR INTO
THE REGION WITH TEMPERATURES CRESTING WELL INTO THE 50S EVERYWHERE
BY AFTERNOON...EVEN WITH LIMITED SUNSHINE.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THERE CONTINUES TO BE SOME TIMING DIFFERENCES WITH FRONTAL PASSAGES
IN THE LONG TERM...AND HOW AMPLIFIED THE MEAN LONGWAVE TROUGH
BECOMES IN THE MID WEEK. THE GFS AND HPC TRENDS ARE FOR A FLATTER
AND BROADER UPPER LEVEL TROUGH WITH SEVERAL SHORTWAVES/FRONTAL
PASSAGE IN THE FLAT/BROAD CYCLONIC FLOW IN THE EARLY TO MID WEEK.
WE ARE LEANING THIS WAY WITH THE FORECAST.
SUNDAY NIGHT INTO MONDAY...THE GFS AND HPC GUIDANCE BOTH HAVE A COLD
FRONT APPROACHING FROM THE ERN GREAT LAKES REGION...OHIO AND MS
VALLEYS. WE GRADUALLY INCREASED THE POPS TO CHC VALUES BY MONDAY.
THE ECMWF IS SLOWER WITH THE FRONT WITH SOME RIDGING INCREASING
ALONG THE EAST COAST. THE LATEST GFS INDICATES SOME COLD AIR
ADVECTION DURING THE DAY ON MONDAY WITH TEMPS FALLING TO +1 TO +5C
FROM NW TO SE OVER THE FCST AREA. LOWS WILL BE MILD MONDAY
MORNING...MAINLY IN THE 40S...AND HIGHS AHEAD OF THE FRONTAL PASSAGE
RANGE FROM THE U50S TO L60S IN THE VALLEYS...AND U40S TO M50S OVER
THE HILLS AND MTNS.
MONDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE BRIEFLY BUILDS IN MONDAY
NIGHT INTO TUESDAY IN THE RELATIVELY FLAT MID LEVEL FLOW. A WAVE
MOVES ALONG THE OLD COLD FRONTAL BOUNDARY WHICH IS STATIONARY OVER
THE MID ATLANTIC REGION. THE CHANCES FOR SHOWERS LOOK TO INCREASE
AGAIN...WITH OVER RUNNING PCPN AHEAD OF THE WAVE LATE TUE-TUE
NIGHT. A NORTHERN STREAM DISTURBANCE APPROACHES FROM THE GREAT
LAKES REGION TOWARDS WEDNESDAY WITH ANOTHER BATCH OF SHOWERS...AND
ANOTHER SHOT OF COLD ADVECTION. ONCE THIS FRONT MOVES THROUGH THE
UPPER LEVEL TROUGH AMPLIFIES WITH NW FLOW DOMINATING ALOFT...AND
HIGH PRESSURE BUILDING IN FROM THE CNTRL PLAINS. TEMPS LOOK TO
AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL DURING THIS TIME FRAME.
WEDNESDAY NIGHT INTO THURSDAY...OVERALL LOOKS COLDER AND DRY WITH
PERHAPS SOME LAKE EFFECT OR UPSLOPE RAIN/SNOW SHOWERS NORTH AND WEST
OF THE CAPITAL REGION. H850 TEMPS FINISH THE EXTENDED IN THE 0 TO
-7C RANGE FROM NW TO SE OVER THE FCST AREA...WITH TEMPS FALLING TO
NORMAL OR BELOW NORMAL LEVELS. HIGHS ON THU WILL STRUGGLE TO GET OUT
OF THE 40S.
THIS IS A LOW CONFIDENCE FORECAST...AND WE WILL SEE IF THERE IS
BETTER AGREEMENT IN THE MEDIUM RANGE GUIDANCE OVER THE NEXT FEW
CYCLES.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
COLD FRONT HAS MOVED WELL EAST OF THE KGFL/KALB/KPOU
TERMINALS...WHILE A NARROW BATCH OF SHOWERS LAGS BEHIND THE FRONT
DUE TO THE UPPER LEVEL TROF REMAINING FARTHER BACK TO THE WEST
OVER THE GREAT LAKES. VFR CONDITIONS WILL PERSIST THROUGH THE
EARLY MORNING HOURS WITH SCATTERED SHOWERS DURING THIS TIME.
SHOWERS SHOULD GENERALLY MOVE EAST OF THE HUDSON VALLEY BY SUNRISE
OR A LITTLE AFTER. ACTIVITY SCATTERED ENOUGH AND LIGHT ENOUGH THAT
PUTTING VCSH INSTEAD OF PUTTING PERIOD OF MVFR CONDITIONS.
WINDS WILL BE NORTHWEST AROUND 5-10 KT THROUGH THE EARLY MORNING
HOURS...BECOMING WEST-NORTHWEST LATER IN THE MORNING AROUND 12-20
KT WITH GUST OF 25-30 KT POSSIBLE ESPECIALLY NEAR KALB WHERE WIND
SPEEDS WILL BE ENHANCED DOWN THE MOHAWK VALLEY. WINDS WILL
DIMINISH THIS EVENING.
OUTLOOK...
FRI NIGHT...VFR/MVFR. ISOLD -SHRASN.
SAT-SUN...VFR. NO SIG WX.
MON...VFR. SLIGHT CHC -SHRA.
TUE...VFR. CHC -SHRA.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE ANTICIPATED THE NEXT 5 DAYS ON THE MAIN STEM
RIVERS.
ANY PRECIPITATION THAT WILL FALL TONIGHT THROUGH FRIDAY NIGHT WILL
BE LIGHT...GENERALLY UNDER A QUARTER OF AN INCH OR LESS. SOME OF
THIS COULD FALL AS SNOW ACROSS THE HIGHER TERRAIN WITH ONLY
LOCALIZED MINOR ACCUMULATIONS.
THE NEXT THREAT OF PRECIPITATION WOULD BE MONDAY INTO TUESDAY BUT
AGAIN FROM THIS VANTAGE POINT...AMOUNTS OF PRECIPITATION (FALLING AS
RAIN) LOOK LIGHT.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
AVIATION...NAS
AREA FORECAST DISCUSSION
NWS ALBANY NY
1009 PM EST THU NOV 10 2011
.SYNOPSIS...
A COLD FRONT WILL SLOWLY MOVE TO OUR EAST TONIGHT. A DISTURBANCE
TO OUR EAST WILL WRAP SOME MOISTURE BACK ACROSS OUR
REGION...MAINLY EAST OF THE HUDSON VALLEY. HOWEVER...SOME LAKE
EFFECT MOISTURE WILL ALSO BRING SHOWERS OF RAIN AND SNOW...MAINLY
TO THE NORTHWEST OF ALBANY. A BRISK WESTERLY FLOW WILL CONTINUE
ON FRIDAY WITH MORE LAKE EFFECT RAIN AND SNOW SHOWERS MAINLY
ACROSS WESTERN AREAS.
&&
.NEAR TERM /UNTIL 7 AM FRIDAY MORNING/...
AS OF 1000 PM...BAND OF SHOWERS FINALLY MOVED EASTWARD INTO THE
HUDSON VALLEY BUT HAS ALSO BROKEN APART IN THE PROCESS. DRIER PUSH
OF AIR RAPIDLY MOVING THROUGH THE MOHAWK VALLEY AND WESTERN
ADIRONDACKS. WILL MENTION RELATIVELY HIGHER POPS FROM THE HUDSON
VALLEY EASTWARD FROM LATE THIS EVENING INTO THE EVENING HOURS
BEFORE TAPERING OFF DURING THE LATTER HALF OF THE OVERNIGHT. TEMPS
ARE ON TRACK...WITH SOME OF THE HIGHER TERRAIN SEEING SNOW SHOWERS
MIX IN WITH RAIN BUT PRECIP WILL CONTINUE TO BE LIGHT. SOME LAKE
EFFECT RESPONSE WILL BE POSSIBLE OFF ONTARIO AS COLDER AIR
CONTINUES TO FILTER IN AT THE SURFACE AND ALOFT...COOLING ENOUGH
FOR CONDITIONAL INSTABILITY TO DEVELOP WITH SCATTERED RAIN/SNOW
SHOWERS DEVELOPING IN THE WESTERN ADIRONDACKS/WESTERN MOHAWK
VALLEY CORRIDOR TOWARDS MORNING.
PREVIOUS NEAR TERM DISCUSSIONS...
AS OF 700 PM...BATCH OF RAIN TO THE EAST HAS EXITED INTO CENTRAL
AND EASTERN NEW ENGLAND...WHILE THE NARROW BUT PERSISTENT BAND OF
SHOWERS TO THE WEST OF ALBANY SLOWLY ADVANCES EASTWARD. WILL
MENTION DRY CONDITIONS FOR THE NEXT FEW HOURS ACROSS WESTERN NEW
ENGLAND...WITH POPS GRADUALLY INCREASING WESTWARD FROM TACONICS TO
THE HUDSON VALLEY. HIGHEST POPS EARLY THIS EVENING WILL REMAIN
OVER THE SOUTHERN ADIRONDACKS...THE MOHAWK AND SCHOHARIE
VALLEYS...AND THE EASTERN CATSKILLS. WHERE MEASURABLE RAINFALL
DOES OCCUR...AMOUNTS WILL BE LIGHT. THE SLOW EASTWARD PROGRESSION
IS DUE TO THE UPPER LEVEL TROF AXIS LAGGING WELL BACK TO THE WEST
ACROSS THE CENTRAL GREAT LAKES.
AS OF 430 PM...DOPPLER RADAR INDICATES TWO AREAS OF RAIN. THE FIRST
ONE TO OUR EAST IS TIED IN TO AN INVERTED TROUGH/DEVELOPING LOW
PRESSURE SPAWNED BY WEAKENING TROPICAL STORM SHAWN TO THE SOUTHEAST
OF CAPE COD. IT LOOKS AS IF ALL THIS MOISTURE WILL NOT ONLY STAY OFF
TO THE EAST OF MOST OF COUNTY WARNING AREA (EXCEPT PERHAPS EASTERN
WINDHAM WERE SHOWERS HAVE MOVED IN)...BUT INITIALLY AS THIS SYSTEM
DEVELOPS...WILL CONTINUE TO INDUCE WEAK SUBSIDENCE OVER THE HUDSON
VALLEY.
THEN TO THE WEST...WAS A LINE OF SHOWERS ASSOCIATED WITH UPWARD
MOTION...OVER THE MOHAWK VALLEY AND JUST INTO THE CATSKILLS...MAINLY
TIED IN THE RR ENTRANCE REGION OF A STRONG UPPER LEVEL JET OVER
125KTS AT THE H250 MB LEVEL. THIS LINE HAS BEEN VERY SLOW TO MOVE
EAST. HOWEVER...AS LOW PRESSURE DEEPENS AND MOVE TO THE GULF OF
MAINE...THE SUBSIDENCE SHOULD WEAKEN LATER THIS EVENING. THIS
WOULD ALLOW THIS LINE TO WORK EAST AND PRODUCE SCATTERED SHOWERS
ACROSS THE REMAINDER OF THE REGION. RAINFALL AMOUNTS WITH THESE
SHOWERS WILL BE LIGHT...GENERALLY UNDER A TENTH OF AN INCH...EXCEPT
A LITTLE HIGHER ACROSS THE MOHAWK VALLEY...MAYBE CLOSER TO A QUARTER
OF AN INCH.
THEN...AS THE STORM CONTINUES TO DEEPEN AND RACE OFF INTO THE
CANADIAN MARITIMES...THE FLOW WILL BECOME NORTHWESTERLY. H850 TEMPS
LOOK TO DROP TO AROUND -5C AND THIS WILL BE COLD ENOUGH TO TRIGGER A
RESPONSE OF LAKE ONTARIO WHERE WATER TEMPS ARE STILL CLOSE TO 50
DEGREES. HOWEVER INITIALLY THERE WILL BE A GOOD AMOUNT OF SHEAR SO
THE REAL LAKE EFFECT WILL LIKELY NOT HAPPEN UNTIL LATER FRIDAY.
OVERNIGHT LOWS WILL FALL BACK INTO THE 30S ACROSS MOST IF NOT ALL OF
THE COUNTY WARNING AREA. A BREEZE WILL PERSIST OUT OF THEN NORTHWEST
5 TO 15 MPH...WITH SOME GUSTS TO 25 MPH.
&&
.SHORT TERM /7 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
FRIDAY/S WEATHER WILL FEATURE VERY TYPICAL MID NOVEMBER CONDITIONS
AS IT WILL BE BRISK WITH GENERALLY MORE CLOUDS THAN SUNSHINE AND
NUISANCE TYPE SHOWERS OR RAIN (OR SNOW IN THE HIGHER TERRAIN).
A STRONG...NEGATIVELY TILTING UPPER LEVEL TROUGH WILL MOVE ACROSS
DURING THE MORNING/EARLY AFTERNOON HOURS. THE MID LEVEL COLD POOL
ASSOCIATED WITH THIS FEATURE REMAINS IMPRESSIVE...WITH -30C AT 500
MB. THIS WILL PROMOTE ENOUGH INSTABILITY...IN COMBINATION WITH
INCREASING LAKE MOISTURE TO ALLOW FOR ISOLATED TO SCATTERED
RAIN/SNOW SHOWERS IN VALLEYS...WITH SCATTERED TO NUMEROUS...MAINLY
SNOW SHOWERS ACROSS HIGHER ELEVATIONS FROM MID MORNING INTO THE
AFTERNOON HOURS. THE SHOWERS MAY CONGEAL INTO MORE LAKE
EFFECT/ENHANCED BANDS DURING THE MID TO LATE AFTERNOON HOURS AFTER A
MORE CELLULAR NATURE DURING THE DAY WITH THE PASSAGE OF THE UPPER
LEVEL TROUGH. THE LOW LEVEL FLOW WOULD FAVOR ANY LATE DAY BANDS TO
OCCUR MAINLY ACROSS EXTREME SW HERKIMER CO...POSSIBLY INTO SCHOHARIE
CO AND THE EASTERN CATSKILLS...WHERE SOME VERY MINOR ACCUMS OF
SNOWFALL COULD OCCUR...PERHAPS LOCALLY UP TO 2 INCHES.
THE LATEST NAM GUIDANCE INDICATES THAT THE WIND WIND WILL NOT GET
QUITE AS STRONG AS EARLIER AS THE STORM MIGHT BECOME QUITE AS DEEP
AND MOVE FASTER. HOWEVER...BUT IT WILL BE GUSTY BY AFTERNOON...WITH
ISOLATED GUSTS UP TO 35-40 MPH ACROSS PORTIONS OF THE MOHAWK VALLEY
AND HIGHER TERRAIN...25-30 MOST OTHER PLACES. TEMPERATURES WILL TOP
AROUND 50 IN THE MID HUDSON VALLEY....UPPER 40S CAPITAL DISTRICT.
ACROSS THE HIGHER TERRAIN HIGHS WILL ONLY REACH 35-40 ACROSS THE
HIGHER TERRAIN OF THE DACKS AND SOUTHERN GREENS.
FRIDAY NIGHT...SOME LAKE EFFECT BANDS OF RAIN/SNOW MAY BE
ONGOING ACROSS THE WESTERN MOHAWK VALLEY...SCHOHARIE VALLEY AND
POSSIBLY INTO THE CAPITAL REGION EARLY. HOWEVER...WITH THE
APPROACH OF ANOTHER SHORTWAVE LATE AT NIGHT...THE LOW LEVEL FLOW
SHOULD BEGIN BACKING...ALLOWING ANY BANDS TO SHIFT NORTH INTO THE
WESTERN ADIRONDACKS. SOME ACCUMS WILL BE POSSIBLE IN THESE
AREAS...PERHAPS ON THE ORDER OF 1-3 INCHES ACROSS THE
ADIRONDACKS...AND LITTLE OF ANY ACCUMULATIONS ELSEWHERE. ANY SNOW
SHOWERS SHOULD GRADUALLY TAPER OFF AFTER MIDNIGHT...ALTHOUGH CLOUDS
MAY LINGER AS MOISTURE REMAINS TRAPPED BENEATH LOWERING INVERSION.
WILL THEREFORE CONTINUE SLIGHTLY ABOVE MOS GUIDANCE FOR MINS...WITH
LOWER 30S ACROSS THE UPPER HUDSON RIVER VALLEYS...AND GENERALLY 20S
ELSEWHERE.
ON SATURDAY...SOME LINGERING SNOW SHOWERS MAY PERSIST SATURDAY
MORNING ACROSS NORTHERN HERKIMER/HAMILTON COUNTIES. OTHERWISE...WE
STILL EXPECT CLOUDS TO GRADUALLY LIFT OUT OF THE REGION BY SATURDAY
AFTERNOON. TEMPERATURES WILL TOP OUT 50-55 IN THE HUDSON VALLEY FROM
ALBANY SOUTHWARD...40S ELSEWHERE.
BY SATURDAY NIGHT THERE STILL MIGHT BE A LAKE EFFECT CLOUDS AROUND
BUT OVERALL IT LOOKS MOSTLY CLEAR. FORECASTING LOW TEMPERATURES WILL
BE A CHALLENGE THAT NIGHT. SURFACE HIGH PRESSURE WILL BE CRESTING
WELL TO OUR SOUTH AND A SOUTHERLY FLOW WILL BEGIN TO DEVELOP...AT
LEAST ALOFT. THE QUESTION IS HOW QUICKLY THE FLOW BEGINS THE WARM
AIR PROCESSES NEAR THE SURFACE. IT MIGHT TAKE A WHILE BUT THE FLOW
WILL ACTUALLY BEGIN BY LATE SATURDAY. FOR NOW...WENT CLOSE THE
MAV/MET GUIDANCE EXCEPT A LITTLE LOWER IN THE USUAL
PLACES...SHELTERED MOUNTAIN VALLEYS.
SUNDAY STILL LOOKS THE BEST PORTION OF THE HOLIDAY WEEKEND. IT WILL
BE A BIT BREEZE WITH A SSW WIND BUT THAT WIND SHOULD MILDER AIR INTO
THE REGION WITH TEMPERATURES CRESTING WELL INTO THE 50S EVERYWHERE
BY AFTERNOON...EVEN WITH LIMITED SUNSHINE.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THERE CONTINUES TO BE SOME TIMING DIFFERENCES WITH FRONTAL PASSAGES
IN THE LONG TERM...AND HOW AMPLIFIED THE MEAN LONGWAVE TROUGH
BECOMES IN THE MID WEEK. THE GFS AND HPC TRENDS ARE FOR A FLATTER
AND BROADER UPPER LEVEL TROUGH WITH SEVERAL SHORTWAVES/FRONTAL
PASSAGE IN THE FLAT/BROAD CYCLONIC FLOW IN THE EARLY TO MID WEEK.
WE ARE LEANING THIS WAY WITH THE FORECAST.
SUNDAY NIGHT INTO MONDAY...THE GFS AND HPC GUIDANCE BOTH HAVE A COLD
FRONT APPROACHING FROM THE ERN GREAT LAKES REGION...OHIO AND MS
VALLEYS. WE GRADUALLY INCREASED THE POPS TO CHC VALUES BY MONDAY.
THE ECMWF IS SLOWER WITH THE FRONT WITH SOME RIDGING INCREASING
ALONG THE EAST COAST. THE LATEST GFS INDICATES SOME COLD AIR
ADVECTION DURING THE DAY ON MONDAY WITH TEMPS FALLING TO +1 TO +5C
FROM NW TO SE OVER THE FCST AREA. LOWS WILL BE MILD MONDAY
MORNING...MAINLY IN THE 40S...AND HIGHS AHEAD OF THE FRONTAL PASSAGE
RANGE FROM THE U50S TO L60S IN THE VALLEYS...AND U40S TO M50S OVER
THE HILLS AND MTNS.
MONDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE BRIEFLY BUILDS IN MONDAY
NIGHT INTO TUESDAY IN THE RELATIVELY FLAT MID LEVEL FLOW. A WAVE
MOVES ALONG THE OLD COLD FRONTAL BOUNDARY WHICH IS STATIONARY OVER
THE MID ATLANTIC REGION. THE CHANCES FOR SHOWERS LOOK TO INCREASE
AGAIN...WITH OVER RUNNING PCPN AHEAD OF THE WAVE LATE TUE-TUE
NIGHT. A NORTHERN STREAM DISTURBANCE APPROACHES FROM THE GREAT
LAKES REGION TOWARDS WEDNESDAY WITH ANOTHER BATCH OF SHOWERS...AND
ANOTHER SHOT OF COLD ADVECTION. ONCE THIS FRONT MOVES THROUGH THE
UPPER LEVEL TROUGH AMPLIFIES WITH NW FLOW DOMINATING ALOFT...AND
HIGH PRESSURE BUILDING IN FROM THE CNTRL PLAINS. TEMPS LOOK TO
AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL DURING THIS TIME FRAME.
WEDNESDAY NIGHT INTO THURSDAY...OVERALL LOOKS COLDER AND DRY WITH
PERHAPS SOME LAKE EFFECT OR UPSLOPE RAIN/SNOW SHOWERS NORTH AND WEST
OF THE CAPITAL REGION. H850 TEMPS FINISH THE EXTENDED IN THE 0 TO
-7C RANGE FROM NW TO SE OVER THE FCST AREA...WITH TEMPS FALLING TO
NORMAL OR BELOW NORMAL LEVELS. HIGHS ON THU WILL STRUGGLE TO GET OUT
OF THE 40S.
THIS IS A LOW CONFIDENCE FORECAST...AND WE WILL SEE IF THERE IS
BETTER AGREEMENT IN THE MEDIUM RANGE GUIDANCE OVER THE NEXT FEW
CYCLES.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
COLD FRONT HAS MOVED WELL EAST OF THE KGFL/KALB/KPOU
TERMINALS...WHILE A NARROW BATCH OF SHOWERS LAGS BEHIND THE FRONT
DUE TO THE UPPER LEVEL TROF REMAINING FARTHER BACK TO THE WEST
OVER THE GREAT LAKES. VFR/MVFR CONDITIONS WILL PERSIST MUCH OF THE
EVENING AND INTO THE OVERNIGHT WITH SCATTERED SHOWERS DURING THIS
TIME. SHOWERS SHOULD GENERALLY MOVE EAST OF THE HUDSON VALLEY
DURING THE LATER HALF OF THE OVERNIGHT PERIOD. ISOLATED TO
SCATTERED LAKE ENHANCED SHOWERS WILL BE POSSIBLE ON
FRIDAY...MAINLY FROM KALB NORTHWARD TO KGFL WITH GENERALLY VFR
CONDITIONS PREVAILING BUT INTERVALS OF MVFR ALSO POSSIBLE.
WINDS WILL BE NORTHWEST AROUND 5-10 KT TONIGHT...BECOMING WEST-
NORTHWEST AROUND 12-20 KT WITH GUST OF 25-30 KT POSSIBLE
ESPECIALLY NEAR KALB WHERE WIND SPEEDS WILL BE ENHANCED DOWN THE
MOHAWK VALLEY.
OUTLOOK...
FRI NIGHT...VFR/MVFR. ISOLD -SHRASN.
SAT-SUN...VFR. NO SIG WX.
MON...VFR. SLIGHT CHC -SHRA.
TUE...VFR. CHC -SHRA.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE ANTICIPATED THE NEXT 5 DAYS ON THE MAIN STEM
RIVERS.
ANY PRECIPITATION THAT WILL FALL TONIGHT THROUGH FRIDAY NIGHT WILL
BE LIGHT...GENERALLY UNDER A QUARTER OF AN INCH OR LESS. SOME OF
THIS COULD FALL AS SNOW ACROSS THE HIGHER TERRAIN WITH ONLY
LOCALIZED MINOR ACCUMULATIONS.
THE NEXT THREAT OF PRECIPITATION WOULD BE MONDAY INTO TUESDAY BUT
AGAIN FROM THIS VANTAGE POINT...AMOUNTS OF PRECIPITATION (FALLING AS
RAIN) LOOK LIGHT.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/JPV
NEAR TERM...HWJIV/JPV
SHORT TERM...HWJIV
LONG TERM...WASULA
AVIATION...JPV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
713 PM EST THU NOV 10 2011
.SYNOPSIS...
A COLD FRONT WILL SLOWLY MOVE TO OUR EAST TONIGHT. A DISTURBANCE
TO OUR EAST WILL WRAP SOME MOISTURE BACK ACROSS OUR
REGION...MAINLY EAST OF THE HUDSON VALLEY. HOWEVER...SOME LAKE
EFFECT MOISTURE WILL ALSO BRING SHOWERS OF RAIN AND SNOW...MAINLY
TO THE NORTHWEST OF ALBANY. A BRISK WESTERLY FLOW WILL CONTINUE
ON FRIDAY WITH MORE LAKE EFFECT RAIN AND SNOW SHOWERS MAINLY
ACROSS WESTERN AREAS.
&&
.NEAR TERM /UNTIL 7 AM FRIDAY MORNING/...
AS OF 700 PM...BATCH OF RAIN TO THE EAST HAS EXITED INTO CENTRAL
AND EASTERN NEW ENGLAND...WHILE THE NARROW BUT PERSISTENT BAND OF
SHOWERS TO THE WEST OF ALBANY SLOWLY ADVANCES EASTWARD. WILL
MENTION DRY CONDITIONS FOR THE NEXT FEW HOURS ACROSS WESTERN NEW
ENGLAND...WITH POPS GRADUALLY INCREASING WESTWARD FROM TACONICS TO
THE HUDSON VALLEY. HIGHEST POPS EARLY THIS EVENING WILL REMAIN
OVER THE SOUTHERN ADIRONDACKS...THE MOHAWK AND SCHOHARIE
VALLEYS...AND THE EASTERN CATSKILLS. WHERE MEASURABLE RAINFALL
DOES OCCUR...AMOUNTS WILL BE LIGHT. THE SLOW EASTWARD PROGRESSION
IS DUE TO THE UPPER LEVEL TROF AXIS LAGGING WELL BACK TO THE WEST
ACROSS THE CENTRAL GREAT LAKES.
PREVIOUS NEAR TERM DISCUSSION...
AS OF 430 PM...DOPPLER RADAR INDICATES TWO AREAS OF RAIN. THE FIRST
ONE TO OUR EAST IS TIED IN TO AN INVERTED TROUGH/DEVELOPING LOW
PRESSURE SPAWNED BY WEAKENING TROPICAL STORM SHAWN TO THE SOUTHEAST
OF CAPE COD. IT LOOKS AS IF ALL THIS MOISTURE WILL NOT ONLY STAY OFF
TO THE EAST OF MOST OF COUNTY WARNING AREA (EXCEPT PERHAPS EASTERN
WINDHAM WERE SHOWERS HAVE MOVED IN)...BUT INITIALLY AS THIS SYSTEM
DEVELOPS...WILL CONTINUE TO INDUCE WEAK SUBSIDENCE OVER THE HUDSON
VALLEY.
THEN TO THE WEST...WAS A LINE OF SHOWERS ASSOCIATED WITH UPWARD
MOTION...OVER THE MOHAWK VALLEY AND JUST INTO THE CATSKILLS...MAINLY
TIED IN THE RR ENTRANCE REGION OF A STRONG UPPER LEVEL JET OVER
125KTS AT THE H250 MB LEVEL. THIS LINE HAS BEEN VERY SLOW TO MOVE
EAST. HOWEVER...AS LOW PRESSURE DEEPENS AND MOVE TO THE GULF OF
MAINE...THE SUBSIDENCE SHOULD WEAKEN LATER THIS EVENING. THIS
WOULD ALLOW THIS LINE TO WORK EAST AND PRODUCE SCATTERED SHOWERS
ACROSS THE REMAINDER OF THE REGION. RAINFALL AMOUNTS WITH THESE
SHOWERS WILL BE LIGHT...GENERALLY UNDER A TENTH OF AN INCH...EXCEPT
A LITTLE HIGHER ACROSS THE MOHAWK VALLEY...MAYBE CLOSER TO A QUARTER
OF AN INCH.
THEN...AS THE STORM CONTINUES TO DEEPEN AND RACE OFF INTO THE
CANADIAN MARITIMES...THE FLOW WILL BECOME NORTHWESTERLY. H850 TEMPS
LOOK TO DROP TO AROUND -5C AND THIS WILL BE COLD ENOUGH TO TRIGGER A
RESPONSE OF LAKE ONTARIO WHERE WATER TEMPS ARE STILL CLOSE TO 50
DEGREES. HOWEVER INITIALLY THERE WILL BE A GOOD AMOUNT OF SHEAR SO
THE REAL LAKE EFFECT WILL LIKELY NOT HAPPEN UNTIL LATER FRIDAY.
OVERNIGHT LOWS WILL FALL BACK INTO THE 30S ACROSS MOST IF NOT ALL OF
THE COUNTY WARNING AREA. A BREEZE WILL PERSIST OUT OF THEN NORTHWEST
5 TO 15 MPH...WITH SOME GUSTS TO 25 MPH.
&&
.SHORT TERM /7 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
FRIDAY/S WEATHER WILL FEATURE VERY TYPICAL MID NOVEMBER CONDITIONS
AS IT WILL BE BRISK WITH GENERALLY MORE CLOUDS THAN SUNSHINE AND
NUISANCE TYPE SHOWERS OR RAIN (OR SNOW IN THE HIGHER TERRAIN).
A STRONG...NEGATIVELY TILTING UPPER LEVEL TROUGH WILL MOVE ACROSS
DURING THE MORNING/EARLY AFTERNOON HOURS. THE MID LEVEL COLD POOL
ASSOCIATED WITH THIS FEATURE REMAINS IMPRESSIVE...WITH -30C AT 500
MB. THIS WILL PROMOTE ENOUGH INSTABILITY...IN COMBINATION WITH
INCREASING LAKE MOISTURE TO ALLOW FOR ISOLATED TO SCATTERED
RAIN/SNOW SHOWERS IN VALLEYS...WITH SCATTERED TO NUMEROUS...MAINLY
SNOW SHOWERS ACROSS HIGHER ELEVATIONS FROM MID MORNING INTO THE
AFTERNOON HOURS. THE SHOWERS MAY CONGEAL INTO MORE LAKE
EFFECT/ENHANCED BANDS DURING THE MID TO LATE AFTERNOON HOURS AFTER A
MORE CELLULAR NATURE DURING THE DAY WITH THE PASSAGE OF THE UPPER
LEVEL TROUGH. THE LOW LEVEL FLOW WOULD FAVOR ANY LATE DAY BANDS TO
OCCUR MAINLY ACROSS EXTREME SW HERKIMER CO...POSSIBLY INTO SCHOHARIE
CO AND THE EASTERN CATSKILLS...WHERE SOME VERY MINOR ACCUMS OF
SNOWFALL COULD OCCUR...PERHAPS LOCALLY UP TO 2 INCHES.
THE LATEST NAM GUIDANCE INDICATES THAT THE WIND WIND WILL NOT GET
QUITE AS STRONG AS EARLIER AS THE STORM MIGHT BECOME QUITE AS DEEP
AND MOVE FASTER. HOWEVER...BUT IT WILL BE GUSTY BY AFTERNOON...WITH
ISOLATED GUSTS UP TO 35-40 MPH ACROSS PORTIONS OF THE MOHAWK VALLEY
AND HIGHER TERRAIN...25-30 MOST OTHER PLACES. TEMPERATURES WILL TOP
AROUND 50 IN THE MID HUDSON VALLEY....UPPER 40S CAPITAL DISTRICT.
ACROSS THE HIGHER TERRAIN HIGHS WILL ONLY REACH 35-40 ACROSS THE
HIGHER TERRAIN OF THE DACKS AND SOUTHERN GREENS.
FRIDAY NIGHT...SOME LAKE EFFECT BANDS OF RAIN/SNOW MAY BE
ONGOING ACROSS THE WESTERN MOHAWK VALLEY...SCHOHARIE VALLEY AND
POSSIBLY INTO THE CAPITAL REGION EARLY. HOWEVER...WITH THE
APPROACH OF ANOTHER SHORTWAVE LATE AT NIGHT...THE LOW LEVEL FLOW
SHOULD BEGIN BACKING...ALLOWING ANY BANDS TO SHIFT NORTH INTO THE
WESTERN ADIRONDACKS. SOME ACCUMS WILL BE POSSIBLE IN THESE
AREAS...PERHAPS ON THE ORDER OF 1-3 INCHES ACROSS THE
ADIRONDACKS...AND LITTLE OF ANY ACCUMULATIONS ELSEWHERE. ANY SNOW
SHOWERS SHOULD GRADUALLY TAPER OFF AFTER MIDNIGHT...ALTHOUGH CLOUDS
MAY LINGER AS MOISTURE REMAINS TRAPPED BENEATH LOWERING INVERSION.
WILL THEREFORE CONTINUE SLIGHTLY ABOVE MOS GUIDANCE FOR MINS...WITH
LOWER 30S ACROSS THE UPPER HUDSON RIVER VALLEYS...AND GENERALLY 20S
ELSEWHERE.
ON SATURDAY...SOME LINGERING SNOW SHOWERS MAY PERSIST SATURDAY
MORNING ACROSS NORTHERN HERKIMER/HAMILTON COUNTIES. OTHERWISE...WE
STILL EXPECT CLOUDS TO GRADUALLY LIFT OUT OF THE REGION BY SATURDAY
AFTERNOON. TEMPERATURES WILL TOP OUT 50-55 IN THE HUDSON VALLEY FROM
ALBANY SOUTHWARD...40S ELSEWHERE.
BY SATURDAY NIGHT THERE STILL MIGHT BE A LAKE EFFECT CLOUDS AROUND
BUT OVERALL IT LOOKS MOSTLY CLEAR. FORECASTING LOW TEMPERATURES WILL
BE A CHALLENGE THAT NIGHT. SURFACE HIGH PRESSURE WILL BE CRESTING
WELL TO OUR SOUTH AND A SOUTHERLY FLOW WILL BEGIN TO DEVELOP...AT
LEAST ALOFT. THE QUESTION IS HOW QUICKLY THE FLOW BEGINS THE WARM
AIR PROCESSES NEAR THE SURFACE. IT MIGHT TAKE A WHILE BUT THE FLOW
WILL ACTUALLY BEGIN BY LATE SATURDAY. FOR NOW...WENT CLOSE THE
MAV/MET GUIDANCE EXCEPT A LITTLE LOWER IN THE USUAL
PLACES...SHELTERED MOUNTAIN VALLEYS.
SUNDAY STILL LOOKS THE BEST PORTION OF THE HOLIDAY WEEKEND. IT WILL
BE A BIT BREEZE WITH A SSW WIND BUT THAT WIND SHOULD MILDER AIR INTO
THE REGION WITH TEMPERATURES CRESTING WELL INTO THE 50S EVERYWHERE
BY AFTERNOON...EVEN WITH LIMITED SUNSHINE.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THERE CONTINUES TO BE SOME TIMING DIFFERENCES WITH FRONTAL PASSAGES
IN THE LONG TERM...AND HOW AMPLIFIED THE MEAN LONGWAVE TROUGH
BECOMES IN THE MID WEEK. THE GFS AND HPC TRENDS ARE FOR A FLATTER
AND BROADER UPPER LEVEL TROUGH WITH SEVERAL SHORTWAVES/FRONTAL
PASSAGE IN THE FLAT/BROAD CYCLONIC FLOW IN THE EARLY TO MID WEEK.
WE ARE LEANING THIS WAY WITH THE FORECAST.
SUNDAY NIGHT INTO MONDAY...THE GFS AND HPC GUIDANCE BOTH HAVE A COLD
FRONT APPROACHING FROM THE ERN GREAT LAKES REGION...OHIO AND MS
VALLEYS. WE GRADUALLY INCREASED THE POPS TO CHC VALUES BY MONDAY.
THE ECMWF IS SLOWER WITH THE FRONT WITH SOME RIDGING INCREASING
ALONG THE EAST COAST. THE LATEST GFS INDICATES SOME COLD AIR
ADVECTION DURING THE DAY ON MONDAY WITH TEMPS FALLING TO +1 TO +5C
FROM NW TO SE OVER THE FCST AREA. LOWS WILL BE MILD MONDAY
MORNING...MAINLY IN THE 40S...AND HIGHS AHEAD OF THE FRONTAL PASSAGE
RANGE FROM THE U50S TO L60S IN THE VALLEYS...AND U40S TO M50S OVER
THE HILLS AND MTNS.
MONDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE BRIEFLY BUILDS IN MONDAY
NIGHT INTO TUESDAY IN THE RELATIVELY FLAT MID LEVEL FLOW. A WAVE
MOVES ALONG THE OLD COLD FRONTAL BOUNDARY WHICH IS STATIONARY OVER
THE MID ATLANTIC REGION. THE CHANCES FOR SHOWERS LOOK TO INCREASE
AGAIN...WITH OVER RUNNING PCPN AHEAD OF THE WAVE LATE TUE-TUE
NIGHT. A NORTHERN STREAM DISTURBANCE APPROACHES FROM THE GREAT
LAKES REGION TOWARDS WEDNESDAY WITH ANOTHER BATCH OF SHOWERS...AND
ANOTHER SHOT OF COLD ADVECTION. ONCE THIS FRONT MOVES THROUGH THE
UPPER LEVEL TROUGH AMPLIFIES WITH NW FLOW DOMINATING ALOFT...AND
HIGH PRESSURE BUILDING IN FROM THE CNTRL PLAINS. TEMPS LOOK TO
AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL DURING THIS TIME FRAME.
WEDNESDAY NIGHT INTO THURSDAY...OVERALL LOOKS COLDER AND DRY WITH
PERHAPS SOME LAKE EFFECT OR UPSLOPE RAIN/SNOW SHOWERS NORTH AND WEST
OF THE CAPITAL REGION. H850 TEMPS FINISH THE EXTENDED IN THE 0 TO
-7C RANGE FROM NW TO SE OVER THE FCST AREA...WITH TEMPS FALLING TO
NORMAL OR BELOW NORMAL LEVELS. HIGHS ON THU WILL STRUGGLE TO GET OUT
OF THE 40S.
THIS IS A LOW CONFIDENCE FORECAST...AND WE WILL SEE IF THERE IS
BETTER AGREEMENT IN THE MEDIUM RANGE GUIDANCE OVER THE NEXT FEW
CYCLES.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
COLD FRONT HAS MOVED WELL EAST OF THE KGFL/KALB/KPOU
TERMINALS...WHILE A NARROW BATCH OF SHOWERS LAGS BEHIND THE FRONT
DUE TO THE UPPER LEVEL TROF REMAINING FARTHER BACK TO THE WEST
OVER THE GREAT LAKES. VFR/MVFR CONDITIONS WILL PERSIST MUCH OF THE
EVENING AND INTO THE OVERNIGHT WITH SCATTERED SHOWERS DURING THIS
TIME. SHOWERS SHOULD GENERALLY MOVE EAST OF THE HUDSON VALLEY
DURING THE LATER HALF OF THE OVERNIGHT PERIOD. ISOLATED TO
SCATTERED LAKE ENHANCED SHOWERS WILL BE POSSIBLE ON
FRIDAY...MAINLY FROM KALB NORTHWARD TO KGFL WITH GENERALLY VFR
CONDITIONS PREVAILING BUT INTERVALS OF MVFR ALSO POSSIBLE.
WINDS WILL BE NORTHWEST AROUND 5-10 KT TONIGHT...BECOMING WEST-
NORTHWEST AROUND 12-20 KT WITH GUST OF 25-30 KT POSSIBLE
ESPECIALLY NEAR KALB WHERE WIND SPEEDS WILL BE ENHANCED DOWN THE
MOHAWK VALLEY.
OUTLOOK...
FRI NIGHT...VFR/MVFR. ISOLD -SHRASN.
SAT-SUN...VFR. NO SIG WX.
MON...VFR. SLIGHT CHC -SHRA.
TUE...VFR. CHC -SHRA.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE ANTICIPATED THE NEXT 5 DAYS ON THE MAIN STEM
RIVERS.
ANY PRECIPITATION THAT WILL FALL TONIGHT THROUGH FRIDAY NIGHT WILL
BE LIGHT...GENERALLY UNDER A QUARTER OF AN INCH OR LESS. SOME OF
THIS COULD FALL AS SNOW ACROSS THE HIGHER TERRAIN WITH ONLY
LOCALIZED MINOR ACCUMULATIONS.
THE NEXT THREAT OF PRECIPITATION WOULD BE MONDAY INTO TUESDAY BUT
AGAIN FROM THIS VANTAGE POINT...AMOUNTS OF PRECIPITATION (FALLING AS
RAIN) LOOK LIGHT.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/JPV
NEAR TERM...HWJIV/JPV
SHORT TERM...HWJIV
LONG TERM...WASULA
AVIATION...WASULA
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1221 AM EST FRI NOV 11 2011
.AVIATION.../06Z TAFS/
WATER VAPOR LOOP SHOWING UPR LEVEL TROF MOVG EAST OF THE AREA INTO
THE LWR GRTLKS EARLY THIS MORNING AND BULK OF LAKE ENHANCED
SHOWERS NOW LOCATED NE OF THE TERMINALS. A FEW RN/SN SHOWERS COULD
STILL MOVE OVER SBN TERMINAL NEXT COUPLE OF HOURS BUT NO SGFNT
IMPACT ON CIGS/VSBYS EXPECTED WITH VFR CONDITIONS CONTG AT BOTH
TERMINALS OVERNIGHT AND THROUGH THE PERIOD. RIDGE WILL MOVE ACROSS
THE AREA TODAY WITH SWLY WINDS AND SOME WAA MID CLOUDS
OVERSPREADING THE AREA IN ITS WAKE.
&&
.PREV DISCUSSION...
SHORT TERM...
SURFACE TROUGH ASSOCIATED WITH SHARP MID LEVEL TROUGH MOVING THROUGH
FORECAST AREA TODAY. CLOUDS HAVE INCREASED IN WAKE OF SURFACE TROUGH
WITH COLD AIR ADVECTION ALONG WITH INCREASED SYNOPTIC MOISTURE.
OUTSIDE OF LAKE EFFECT AREAS...PCPN HAS BEEN MINIMAL. FLOW WILL
BECOME NORTHWEST BY LATE AFTERNOON AND THIS EVENING BEHIND TROUGH.
DELTA T VALUES WILL BE IN MID TEENS WITH DEEP MOIST LAYER AND BRIEF
PERIOD OF OPTIMAL DENDRITIC GROWTH. EQUILIBRIUM HEIGHTS 14-18KFT
THIS EVENING WITH LAKE INDUCED CAPES BETWEEN 400-500 J/KG. WITH
LOSS OF BOUNDARY LAYER HEATING THIS EVENING CONCERNED LAKE EFFECT
PCPN COULD CONGEAL INTO A FEW DECENT BANDS EARLY THIS EVENING WITH
BRIEF MODERATE SNOW SHOWERS AND SOME ACCUMS ON MAINLY GRASSY
AREAS. RUC13 AND LOCAL WRF SHOWING THIS WITH PERIOD OF STRONG LOW
LEVEL OMEGA THROUGH ABOUT 03Z COINCIDENT WITH SYNOPTIC MOISTURE
CURRENTLY UPSTREAM ACROSS WI. HAVE INCREASED POPS ALONG WITH
ACCUMS OF 1 TO 2 INCHES ACROSS MI COUNTIES WHERE BEST POTENTIAL
LIES FOR SOME OF THESE ACCUMS. STILL EXPECT SOME SLEET TO MIX IN
WITHIN CONVECTIVE CELLS LATE THIS AFTERNOON AND EARLY EVENING.
PCPN QUICKLY ENDS OVERNIGHT AS DRIER AIR MOVES IN WITH CRASHING
INVERSION HEIGHTS AND BACKING WINDS AS SURFACE RIDGING MOVES IN.
FAST MOVING SHORT WAVE PASSING THROUGH FRIDAY WILL HELP BACK WINDS
ALONG WITH WAA AND MID TO HIGH CLOUDS. PARTIAL CLEARING IN WAKE OF
THIS WAVE LATER FRIDAY WITH WAA CONTINUING BUT NO PCPN EXPECTED FROM
THIS WEAK WAVE.
LONG TERM...
SUNDAY THROUGH THURSDAY...
CHALLENGING FORECAST IN THE EXTENDED AS THE ORIENTATION OF THE NOAM
TROF WILL DICTATE THE AMOUNT OF WARMUP SUNDAY. TIMING OF THE
INDIVIDUAL SHORTWAVES WILL DRIVE THE AMOUNT/EXTENT/DURATION OF
PRECIPITATION.
EXTENDED MODELS IN GENERAL AGREEMENT WITH A BROAD TROF OVER THE
CENTRAL US FROM SUNDAY THROUGH THURSDAY. BUT EACH DIFFERS ON TIMING
AND DEPTH OF VARIOUS SHORT WAVES IN THE BROAD CYCLONIC FLOW. WITH
RIDGING OVER THE PACIFIC THE FAVORED DOWNSTREAM TROFFING IS A
REASONABLE SOLUTION. AN EVEN BLEND OF THE EXTENDED MODELS AND THE
ENSEMBLE MEAN PROVIDE A REASONABLE SOLUTION AND CAUSE A MINIMAL
AMOUNT OF CHANGE TO THE CURRENT GRIDDED FORECASTS.
HAVE CONTINUED THE PREVIOUS FORECAST TREND OF ABOVE NORMAL
TEMPERATURES FOR SUNDAY INTO MONDAY. WHILE THE PLACEMENT AND TIMING
OF THE NEXT COLD FRONT IS PROBLEMATIC...HIGH CONFIDENCE THAT
PRECIPITATION WILL BEGIN DURING THE OVERNIGHT SUNDAY INTO MONDAY
WITH SHOWERS LASTING DURING THE EARLY PART OF THE WEEK.
AS THE FLOW BECOMES MORE WESTERLY-NORTHWESTERLY EXPECT TO SEE
SHOWERS DEVELOPING ON THE LEE SIDE OF LAKE MICHIGAN DURING THE
LATTER PART OF THE EXTENDED PERIOD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EST SATURDAY FOR LMZ043-046.
&&
$$
SHORT TERM...LASHLEY
LONG TERM...LEWIS
AVIATION...JT
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
730 PM EST THU NOV 10 2011
.AVIATION /00 UTC/...
EPISODIC BURSTS OF LAKE EFFECT SHSN TO CONT THIS EVE ACRS SWRN
MI/NCNTL IN. PROGGED BACKING WINDS BY 06 UTC/LWRG SUBSIDENCE
INVERSION SHOULD KEEP CONFINE TEMPO IFR VSBYS AT KSBN TO ABOUT FIRST
FOUR HOURS OF FCST. SUBSTANTIAL BANDS STILL NW OF KFWA AIRFIELD TO
MAINTAIN INTENSITY FOR AT LEAST MVFR MET CONDS NEXT FEW HOURS...WITH
CHC IFR CONDS TOO LOW FOR INCLUSION. BACKED FLOW/ADVANCING MIDCLD
DECK AHEAD OF WEAK CLIPPER SYSTEM ADVANCING INTO FAR WRN GRTLKS BY
END OF FCST PD.
&&
.SHORT TERM...
SURFACE TROUGH ASSOCIATED WITH SHARP MID LEVEL TROUGH MOVING THROUGH
FORECAST AREA TODAY. CLOUDS HAVE INCREASED IN WAKE OF SURFACE TROUGH
WITH COLD AIR ADVECTION ALONG WITH INCREASED SYNOPTIC MOISTURE.
OUTSIDE OF LAKE EFFECT AREAS...PCPN HAS BEEN MINIMAL. FLOW WILL
BECOME NORTHWEST BY LATE AFTERNOON AND THIS EVENING BEHIND TROUGH.
DELTA T VALUES WILL BE IN MID TEENS WITH DEEP MOIST LAYER AND BRIEF
PERIOD OF OPTIMAL DENDRITIC GROWTH. EQUILIBRIUM HEIGHTS 14-18KFT
THIS EVENING WITH LAKE INDUCED CAPES BETWEEN 400-500 J/KG. WITH
LOSS OF BOUNDARY LAYER HEATING THIS EVENING CONCERNED LAKE EFFECT
PCPN COULD CONGEAL INTO A FEW DECENT BANDS EARLY THIS EVENING WITH
BRIEF MODERATE SNOW SHOWERS AND SOME ACCUMS ON MAINLY GRASSY
AREAS. RUC13 AND LOCAL WRF SHOWING THIS WITH PERIOD OF STRONG LOW
LEVEL OMEGA THROUGH ABOUT 03Z COINCIDENT WITH SYNOPTIC MOISTURE
CURRENTLY UPSTREAM ACROSS WI. HAVE INCREASED POPS ALONG WITH
ACCUMS OF 1 TO 2 INCHES ACROSS MI COUNTIES WHERE BEST POTENTIAL
LIES FOR SOME OF THESE ACCUMS. STILL EXPECT SOME SLEET TO MIX IN
WITHIN CONVECTIVE CELLS LATE THIS AFTERNOON AND EARLY EVENING.
PCPN QUICKLY ENDS OVERNIGHT AS DRIER AIR MOVES IN WITH CRASHING
INVERSION HEIGHTS AND BACKING WINDS AS SURFACE RIDGING MOVES IN.
FAST MOVING SHORT WAVE PASSING THROUGH FRIDAY WILL HELP BACK WINDS
ALONG WITH WAA AND MID TO HIGH CLOUDS. PARTIAL CLEARING IN WAKE OF
THIS WAVE LATER FRIDAY WITH WAA CONTINUING BUT NO PCPN EXPECTED FROM
THIS WEAK WAVE.
&&
.LONG TERM...
SUNDAY THROUGH THURSDAY...
CHALLENGING FORECAST IN THE EXTENDED AS THE ORIENTATION OF THE NOAM
TROF WILL DICTATE THE AMOUNT OF WARMUP SUNDAY. TIMING OF THE
INDIVIDUAL SHORTWAVES WILL DRIVE THE AMOUNT/EXTENT/DURATION OF
PRECIPITATION.
EXTENDED MODELS IN GENERAL AGREEMENT WITH A BROAD TROF OVER THE
CENTRAL US FROM SUNDAY THROUGH THURSDAY. BUT EACH DIFFERS ON TIMING
AND DEPTH OF VARIOUS SHORT WAVES IN THE BROAD CYCLONIC FLOW. WITH
RIDGING OVER THE PACIFIC THE FAVORED DOWNSTREAM TROFFING IS A
REASONABLE SOLUTION. AN EVEN BLEND OF THE EXTENDED MODELS AND THE
ENSEMBLE MEAN PROVIDE A REASONABLE SOLUTION AND CAUSE A MINIMAL
AMOUNT OF CHANGE TO THE CURRENT GRIDDED FORECASTS.
HAVE CONTINUED THE PREVIOUS FORECAST TREND OF ABOVE NORMAL
TEMPERATURES FOR SUNDAY INTO MONDAY. WHILE THE PLACEMENT AND TIMING
OF THE NEXT COLD FRONT IS PROBLEMATIC...HIGH CONFIDENCE THAT
PRECIPITATION WILL BEGIN DURING THE OVERNIGHT SUNDAY INTO MONDAY
WITH SHOWERS LASTING DURING THE EARLY PART OF THE WEEK.
AS THE FLOW BECOMES MORE WESTERLY-NORTHWESTERLY EXPECT TO SEE
SHOWERS DEVELOPING ON THE LEE SIDE OF LAKE MICHIGAN DURING THE
LATTER PART OF THE EXTENDED PERIOD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EST SATURDAY FOR LMZ043-046.
&&
$$
SHORT TERM...LASHLEY
LONG TERM...LEWIS
AVIATION...MURPHY
AREA FORECAST DISCUSSION
NWS TOPEKA KS
246 PM CST SAT NOV 12 2011
.DISCUSSION...
SHORT TERM FORECAST (TONIGHT AND SUNDAY)...
20Z WATER VAPOR IMAGERY AND RUC ANALYSIS SHOWS MOSTLY ZONAL FLOW
OVER THE CENTRAL PART OF U.S. EMBEDDED WITHIN THE W-SW MID/UPPER
LEVEL FLOW IS A WEAK SHORTWAVE TROUGH WHICH HAS SPAWNED INCREASING
CLOUD COVER OVER THE CENTRAL MISSOURI AND NORTHERN ARKANSAS.
ALTHOUGH THE WEAK SHORTWAVE TROUGH HAS MOVED OVER NORTHEAST KANSAS
DRY AIR OVER THE AREA HAS PREVENTED MUCH IN THE WAY OF CLOUD
FORMATION. THUS MOSTLY CLEAR SKIES ARE EXPECTED FOR THE REST OF THE
DAY AND OVERNIGHT. EXPECT THE GUSTY WINDS TO TAPER OFF OVERNIGHT AS
DIURNAL DECOUPLING BEGINS SHORTLY AFTER SUNSET. THE SURFACE PRESSURE
GRADIENT WILL REMAIN FAIRLY TIGHT OVERNIGHT...SO EXPECT WESTERLY
WINDS TO REMAIN IN THE 10 TO 15 MPH RANGE OVERNIGHT. BY LATE
SATURDAY NIGHT/EARLY SUNDAY MORNING A FAIRLY SHARP AND QUICKLY
MOVING 500 MB SHORTWAVE TROUGH WILL PUSH ACROSS THE NORTHERN PLAINS.
THE ATMOSPHERIC COLUMN WILL REMAIN RATHER DRY AND THE BEST LIFT
ASSOCIATED WITH THIS TROUGH WILL REMAIN WELL TO THE NORTH. AS A
RESULT OF THOSE FACTORS...DO NOT EXPECT ANY RAIN IN NORTHEAST
KANSAS. BY EARLY SUNDAY MORNING THE SURFACE LOW SITUATED ACROSS THE
NORTHERN TIER WILL MOVE TO THE EAST...BRINGING WEST-NORTHWEST
SURFACE FLOW TO NORTHEAST KANSAS ON SUNDAY. WEAK COLD AIR ADVECTION
BEHIND THE COOL FRONT WILL KEEP TEMPS ON SUNDAY IN THE UPPER 50S TO
LOWER 60S WITH INCREASING W-NW WINDS OF 15 TO 25 MPH.
JL
MEDIUM RANGE FORECAST (SUNDAY NIGHT THROUGH TUESDAY)
SUNDAY NIGHT THROUGH MONDAY NIGHT...A BROAD LONGER WAVE LENGTH UPPER
LEVEL TROUGH WILL TRANSLATE EASTWARD ACROSS THE PLAINS. SHORTER WAVE
LENGTH UPPER TROUGHS WILL DIG SOUTHEAST ACROSS THE HIGH PLAINS AND
LIFT NORTHEAST INTO THE MIDWEST. THE DEEPER 850MB MOISTURE WILL
REMAIN WELL SOUTH AND EAST OF THE CWA...THUS THE LOW-LEVELS OF THE
ATMOSPHERE SHOULD REMAIN RELATIVELY DRY. THERE MAY ENOUGH ASCENT
AHEAD OF AN H5 TROUGH LIFTING NORTHEAST ACROSS EASTERN KS SUNDAY
NIGHT FOR AN INCREASE IN HIGH AND MID LEVEL CLOUDINESS AND POSSIBLY
SOME SPRINKLES. HIGHS MONDAY WILL BE NEAR 60 NORTH OF INTERSTATE
70...WITH LOWER 60S SOUTH OF INTERSTATE 70.
TUESDAY...AS THE LONGER WAVE LENGTH H5 TROUGH AXIS SHIFTS EAST OF
THE PLAINS A SURFACE COLD FRONT WILL PUSH SOUTHWARD THROUGH THE CWA
TUESDAY MORNING. HIGHS WILL ONLY REACH THE UPPER 40S ALONG THE NE
BORDER WITH MID 50S POSSIBLE SOUTH OF I-35...THOUGH HIGHS MAY BE
COOLER IF FROPA OCCURS EARLIER ON TUESDAY MORNING. A SFC RIDGE WILL
BUILD SOUTHWARD ACROSS WESTERN KS THROUGH THE AFTERNOON HOUR. SKIES
WILL BECOME MOSTLY SUNNY.
GARGAN
EXTENDED FORECAST (TUESDAY NIGHT THROUGH SATURDAY)
ZONAL FLOW ALOFT WILL BE THE STORY FOR MOST OF THE WORK WEEK WITH
DRY CONDITIONS AND TEMPERATURES NEAR NORMAL. DROPPED TEMPERATURES A
COUPLE OF DEGREE BELOW GUIDANCE ON WEDNESDAY WITH 850 MB
TEMPERATURES IN THE -5 TO -7 CELSIUS RANGE...LIGHT NORTHWEST WINDS
...CLEAR SKIES AND SURFACE HIGH PRESSURE OVER THE CENTRAL U.S. ON
THURSDAY WINDS WILL SHIFT AROUND TO THE SOUTH AS SURFACE HIGH
PRESSURE MOVES EAST INTO THE MID MISSISSIPPI RIVER VALLEY.
WARM AIR ADVECTION WILL OCCUR AHEAD OF THE NEXT SYSTEM LATE THURSDAY
THROUGH THE REMAINDER OF THE FORECAST AS LEE CYCLOGENESIS TAKES
PLACE. HIGH TEMPERATURES WILL PUSH BACK UP INTO THE 60S ACROSS THE
CWA ON FRIDAY AND SATURDAY AHEAD OF THE SURFACE LOW. BOTH THE 12Z
GFS AND ECMWF ARE INDICATING JUST ENOUGH MOISTURE AHEAD OF THIS
SYSTEM FOR A FEW SHOWERS TO DEVELOP ON SATURDAY WITH THE BEST
CHANCES ACROSS EASTERN PORTIONS OF THE CWA. AT THIS TIME HAVE
MENTIONED A SLIGHT CHANCE OF SHOWERS WITH BOTH THE GFS AND ECMWF
ADVERTISING ENOUGH MOISTURE RETURN FOR A FEW SHOWERS TO DEVELOP ON
SATURDAY.
ANDERSON
&&
.AVIATION...
VFR CONDITIONS EXPECTED THROUGH REMAINDER OF THE FORECAST PERIOD.
GUSTY WINDS WILL TAPER OFF AFTER SUNSET. STRONG LOW LEVEL JET WILL
BRING WIND SHEAR CONCERNS OVERNIGHT AS 800 FOOT WINDS WILL BE IN
THE 45 TO 50 KNOT RANGE.
JL
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1140 PM CST FRI NOV 11 2011
...UPDATE TO AVIATION...
.DISCUSSION...
SHORT TERM FORECAST (TONIGHT AND SATURDAY)...
20Z WATER VAPOR IMAGERY AND RUC ANALYSIS SHOWS A WEAK UPPER RIDGE TO
THE WEST OF THE FORECAST AREA WITH A WEAKENING TROUGH NORTHEAST OF
THE GREAT LAKES REGION AND WEST-NORTHWEST FLOW OVER THE CENTRAL
PLAINS REGION. THE SURFACE RIDGE CURRENTLY SITS OVER THE MISSISSIPPI
RIVER DELTA WITH A SURFACE TROUGH CURRENTLY OVER MANITOBA CANADA
WITH A LOOSE SURFACE PRESSURE GRADIENT ACROSS THE CENTRAL PART OF
THE U.S. EXPECT WINDS TO REMAIN IN THE 10 TO 15 MPH RANGE WITH GUSTS
OF UP TO 20 MPH AS LOW LEVEL WINDS WILL OCCASIONALLY MIX TO THE
SURFACE. OVERNIGHT SOUTH-SOUTHWEST WINDS SHOULD REMAIN FAIRLY
LIGHT...BUT WILL BE STRONG ENOUGH TO KEEP TEMPERATURES SLIGHTLY
WARMER THAN THE PREVIOUS NIGHT. FOR SATURDAY THE PRESSURE GRADIENT
BETWEEN THE SOUTHERN SURFACE HIGH AND THE NORTHERN SURFACE LOW WILL
TIGHTEN AND WILL BRING STRONGER WINDS. THE TIGHTEST GRADIENT WILL
REMAIN OVER EASTERN OKLAHOMA...ARKANSAS...AND SOUTHERN MISSOURI SO
COUNTIES ACROSS EAST CENTRAL KANSAS WILL EXPERIENCE THE STRONGEST
WINDS ON SATURDAY...WITH NORTH CENTRAL KANSAS EXPERIENCING THE
WEAKER SURFACE PRESSURE GRADIENT AND CONSEQUENTLY THE LIGHTER WINDS.
850 MB JET WILL MOVE OVER THE AREA EARLY SATURDAY MORNING...AND BY
MID DAY ON SATURDAY NEARLY DRY ADIABATIC LAPSE RATES TO AROUND 850
MB WILL ALLOW MIXING OF 30 TO 35 KNOT WINDS TO THE SURFACE.
TEMPERATURES WILL ALSO REMAIN RATHER WARM IN SATURDAY AS SOUTHWEST
WINDS AND GOOD INSOLATION BRING TEMPERATURES BACK INTO THE MID 60S.
JL
MID-RANGE FORECAST (SATURDAY NIGHT THROUGH MONDAY)
SATURDAY NIGHT...AN UPPER LEVEL TROUGH WILL MOVE EAST ACROSS THE
CENTRAL AND NORTHERN PLAINS. THE LOW-LEVELS OF THE ATMOSPHERE LOOK
DRY ENOUGH THAT NO MEASURABLE RAINFALL IS EXPECTED. HIGH AND MID
CLOUDS WILL INCREASE THROUGH THE NIGHT AND A WEAK COLD FRONT WILL
MOVE EASTWARD ACROSS THE CWA.
SUNDAY...LOOKS DRY WITH DECREASING CLOUDS THROUGH THE LATE MORNING
AND EARLY AFTERNOON HOURS. HIGHS WILL REACH THE MID 50S ALONG THE NE
BORDER TO THE LOWER 60S ACROSS EAST CENTRAL KS.
SUNDAY NIGHT AND MONDAY...ANOTHER H5 TROUGH WILL MOVE EAST ACROSS
THE PLAINS. DEEPER 850MB MOISTURE WILL BEGIN TO ADVECT NORTHWARD
BUT 850MB WINDS WILL VEER TO THE SOUTHWEST AS THE H5 TROUGH
APPROACHES THE PLAINS...AND WILL KEEP THE DEEPER MOISTURE SOUTH AND
EAST OF THE CWA. THERE MAY BE ENOUGH LOW AND MID LEVEL MOISTURE
ALONG WITH ASCENT AHEAD OF THE H5 TROUGH FOR SPRINKLES OR ISOLATED
SHOWERS ACROSS EAST CENTRAL KS SUNDAY NIGHT INTO MONDAY MORNING. THE
H5 TROUGH AXIS WILL MOVE ACROSS THE CWA MONDAY AFTERNOON...BRINGING
AN END TO ANY SPRINKLES OR SHOWERS. WESTERLY SURFACE WINDS WILL HELP
TO WARM HIGHS ON MONDAY INTO THE UPPER 50S TO LOWER 60S.
MONDAY NIGHT AND TUESDAY...AN H5 TROUGH WILL DIG SOUTHEAST FROM
WESTERN CANADA AND WILL AMPLIFY ACROSS THE UPPER MIDWEST. THIS WILL
CAUSE A COLD FRONT TO PUSH SOUTHWARD ACROSS THE CWA LATE MONDAY
NIGHT. LOW-LEVEL CAA WILL COOL HIGHS ON TUESDAY INTO THE LOWER TO
MID 50S.
GARGAN
EXTENDED FORECAST (MONDAY NIGHT THROUGH FRIDAY)
ALL MODELS ARE IN AGREEMENT THAT ZONAL UPPER LEVEL FLOW WILL SET UP
MONDAY NIGHT AND WILL CONTINUE FOR MUCH OF THE WORK WEEK. THE PATTERN
WILL KEEP CONDITIONS DRY AND TEMPERATURES NEAR NORMAL FOR THE
CENTRAL U.S DURING THE MIDDLE OF THE WEEK WITH HIGHS IN THE 50S
AND LOWS IN THE 30S.
MODELS ARE INDICATING THAT SURFACE HIGH PRESSURE WILL MOVE TO THE
EAST OF THE AREA ON WEDNESDAY WITH SOUTHERLY FLOW AND WARM AIR
ADVECTION RETURNING TO THE AREA ON THURSDAY. LEE CYCLOGENESIS WILL
TAKE PLACE ON THURSDAY AS AN UPPER LEVEL TROUGH MOVES ON SHORE.
MODELS ARE INDICATING A SHORTWAVE TROUGH WILL MOVE AHEAD OF THE MAIN
UPPER LEVEL TROUGH ON FRIDAY AND WILL MOVE THROUGH THE CENTRAL U.S.
BRINGING A CHANCE OF SHOWERS TO THE CWA. BEST MOISTURE RETURN WILL
BE OVER EASTERN PORTIONS OF THE CWA AND THIS IS WHERE PRECIPITATION
CHANCES WERE ADDED FOR FRIDAY.
ANDERSON
&&
.AVIATION...
VFR CONDITIONS WILL CONTINUE AT ALL TAF SITES THROUGH THE FCST PERIOD
WITH ONLY SCT-BKN HIGH CLOUDS EXPECTED. SOUTH WINDS GENERALLY 4-8KTS
TONIGHT WILL QUICKLY INCREASE TO MAINLY THE 15 TO 25 KT RANGE AROUND
15Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
534 PM CST FRI NOV 11 2011
...UPDATE TO AVIATION...
.DISCUSSION...
SHORT TERM FORECAST (TONIGHT AND SATURDAY)...
20Z WATER VAPOR IMAGERY AND RUC ANALYSIS SHOWS A WEAK UPPER RIDGE TO
THE WEST OF THE FORECAST AREA WITH A WEAKENING TROUGH NORTHEAST OF
THE GREAT LAKES REGION AND WEST-NORTHWEST FLOW OVER THE CENTRAL
PLAINS REGION. THE SURFACE RIDGE CURRENTLY SITS OVER THE MISSISSIPPI
RIVER DELTA WITH A SURFACE TROUGH CURRENTLY OVER MANITOBA CANADA
WITH A LOOSE SURFACE PRESSURE GRADIENT ACROSS THE CENTRAL PART OF
THE U.S. EXPECT WINDS TO REMAIN IN THE 10 TO 15 MPH RANGE WITH GUSTS
OF UP TO 20 MPH AS LOW LEVEL WINDS WILL OCCASIONALLY MIX TO THE
SURFACE. OVERNIGHT SOUTH-SOUTHWEST WINDS SHOULD REMAIN FAIRLY
LIGHT...BUT WILL BE STRONG ENOUGH TO KEEP TEMPERATURES SLIGHTLY
WARMER THAN THE PREVIOUS NIGHT. FOR SATURDAY THE PRESSURE GRADIENT
BETWEEN THE SOUTHERN SURFACE HIGH AND THE NORTHERN SURFACE LOW WILL
TIGHTEN AND WILL BRING STRONGER WINDS. THE TIGHTEST GRADIENT WILL
REMAIN OVER EASTERN OKLAHOMA...ARKANSAS...AND SOUTHERN MISSOURI SO
COUNTIES ACROSS EAST CENTRAL KANSAS WILL EXPERIENCE THE STRONGEST
WINDS ON SATURDAY...WITH NORTH CENTRAL KANSAS EXPERIENCING THE
WEAKER SURFACE PRESSURE GRADIENT AND CONSEQUENTLY THE LIGHTER WINDS.
850 MB JET WILL MOVE OVER THE AREA EARLY SATURDAY MORNING...AND BY
MID DAY ON SATURDAY NEARLY DRY ADIABATIC LAPSE RATES TO AROUND 850
MB WILL ALLOW MIXING OF 30 TO 35 KNOT WINDS TO THE SURFACE.
TEMPERATURES WILL ALSO REMAIN RATHER WARM IN SATURDAY AS SOUTHWEST
WINDS AND GOOD INSOLATION BRING TEMPERATURES BACK INTO THE MID 60S.
JL
MID-RANGE FORECAST (SATURDAY NIGHT THROUGH MONDAY)
SATURDAY NIGHT...AN UPPER LEVEL TROUGH WILL MOVE EAST ACROSS THE
CENTRAL AND NORTHERN PLAINS. THE LOW-LEVELS OF THE ATMOSPHERE LOOK
DRY ENOUGH THAT NO MEASURABLE RAINFALL IS EXPECTED. HIGH AND MID
CLOUDS WILL INCREASE THROUGH THE NIGHT AND A WEAK COLD FRONT WILL
MOVE EASTWARD ACROSS THE CWA.
SUNDAY...LOOKS DRY WITH DECREASING CLOUDS THROUGH THE LATE MORNING
AND EARLY AFTERNOON HOURS. HIGHS WILL REACH THE MID 50S ALONG THE NE
BORDER TO THE LOWER 60S ACROSS EAST CENTRAL KS.
SUNDAY NIGHT AND MONDAY...ANOTHER H5 TROUGH WILL MOVE EAST ACROSS
THE PLAINS. DEEPER 850MB MOISTURE WILL BEGIN TO ADVECT NORTHWARD
BUT 850MB WINDS WILL VEER TO THE SOUTHWEST AS THE H5 TROUGH
APPROACHES THE PLAINS...AND WILL KEEP THE DEEPER MOISTURE SOUTH AND
EAST OF THE CWA. THERE MAY BE ENOUGH LOW AND MID LEVEL MOISTURE
ALONG WITH ASCENT AHEAD OF THE H5 TROUGH FOR SPRINKLES OR ISOLATED
SHOWERS ACROSS EAST CENTRAL KS SUNDAY NIGHT INTO MONDAY MORNING. THE
H5 TROUGH AXIS WILL MOVE ACROSS THE CWA MONDAY AFTERNOON...BRINGING
AN END TO ANY SPRINKLES OR SHOWERS. WESTERLY SURFACE WINDS WILL HELP
TO WARM HIGHS ON MONDAY INTO THE UPPER 50S TO LOWER 60S.
MONDAY NIGHT AND TUESDAY...AN H5 TROUGH WILL DIG SOUTHEAST FROM
WESTERN CANADA AND WILL AMPLIFY ACROSS THE UPPER MIDWEST. THIS WILL
CAUSE A COLD FRONT TO PUSH SOUTHWARD ACROSS THE CWA LATE MONDAY
NIGHT. LOW-LEVEL CAA WILL COOL HIGHS ON TUESDAY INTO THE LOWER TO
MID 50S.
GARGAN
EXTENDED FORECAST (MONDAY NIGHT THROUGH FRIDAY)
ALL MODELS ARE IN AGREEMENT THAT ZONAL UPPER LEVEL FLOW WILL SET UP
MONDAY NIGHT AND WILL CONTINUE FOR MUCH OF THE WORK WEEK. THE PATTERN
WILL KEEP CONDITIONS DRY AND TEMPERATURES NEAR NORMAL FOR THE
CENTRAL U.S DURING THE MIDDLE OF THE WEEK WITH HIGHS IN THE 50S
AND LOWS IN THE 30S.
MODELS ARE INDICATING THAT SURFACE HIGH PRESSURE WILL MOVE TO THE
EAST OF THE AREA ON WEDNESDAY WITH SOUTHERLY FLOW AND WARM AIR
ADVECTION RETURNING TO THE AREA ON THURSDAY. LEE CYCLOGENESIS WILL
TAKE PLACE ON THURSDAY AS AN UPPER LEVEL TROUGH MOVES ON SHORE.
MODELS ARE INDICATING A SHORTWAVE TROUGH WILL MOVE AHEAD OF THE MAIN
UPPER LEVEL TROUGH ON FRIDAY AND WILL MOVE THROUGH THE CENTRAL U.S.
BRINGING A CHANCE OF SHOWERS TO THE CWA. BEST MOISTURE RETURN WILL
BE OVER EASTERN PORTIONS OF THE CWA AND THIS IS WHERE PRECIPITATION
CHANCES WERE ADDED FOR FRIDAY.
ANDERSON
&&
.AVIATION...
VFR CONDITIONS WILL CONTINUE THROUGH THE TERMINAL FORECAST PERIOD
AT ALL TAF SITES WITH ONLY SCATTER HIGH CLOUDS EXPECTED. LIGHT
SOUTH WINDS (UNDER 8 KTS) TONIGHT WILL GENERALLY INCREASE INTO THE
15 TO 25 KT RANGE AFT 15Z ON THROUGH THE REMAINDER OF THE FCST.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
327 PM CST FRI NOV 11 2011
.DISCUSSION...
SHORT TERM FORECAST (TONIGHT AND SATURDAY)...
20Z WATER VAPOR IMAGERY AND RUC ANALYSIS SHOWS A WEAK UPPER RIDGE TO
THE WEST OF THE FORECAST AREA WITH A WEAKENING TROUGH NORTHEAST OF
THE GREAT LAKES REGION AND WEST-NORTHWEST FLOW OVER THE CENTRAL
PLAINS REGION. THE SURFACE RIDGE CURRENTLY SITS OVER THE MISSISSIPPI
RIVER DELTA WITH A SURFACE TROUGH CURRENTLY OVER MANITOBA CANADA
WITH A LOOSE SURFACE PRESSURE GRADIENT ACROSS THE CENTRAL PART OF
THE U.S. EXPECT WINDS TO REMAIN IN THE 10 TO 15 MPH RANGE WITH GUSTS
OF UP TO 20 MPH AS LOW LEVEL WINDS WILL OCCASIONALLY MIX TO THE
SURFACE. OVERNIGHT SOUTH-SOUTHWEST WINDS SHOULD REMAIN FAIRLY
LIGHT...BUT WILL BE STRONG ENOUGH TO KEEP TEMPERATURES SLIGHTLY
WARMER THAN THE PREVIOUS NIGHT. FOR SATURDAY THE PRESSURE GRADIENT
BETWEEN THE SOUTHERN SURFACE HIGH AND THE NORTHERN SURFACE LOW WILL
TIGHTEN AND WILL BRING STRONGER WINDS. THE TIGHTEST GRADIENT WILL
REMAIN OVER EASTERN OKLAHOMA...ARKANSAS...AND SOUTHERN MISSOURI SO
COUNTIES ACROSS EAST CENTRAL KANSAS WILL EXPERIENCE THE STRONGEST
WINDS ON SATURDAY...WITH NORTH CENTRAL KANSAS EXPERIENCING THE
WEAKER SURFACE PRESSURE GRADIENT AND CONSEQUENTLY THE LIGHTER WINDS.
850 MB JET WILL MOVE OVER THE AREA EARLY SATURDAY MORNING...AND BY
MID DAY ON SATURDAY NEARLY DRY ADIABATIC LAPSE RATES TO AROUND 850
MB WILL ALLOW MIXING OF 30 TO 35 KNOT WINDS TO THE SURFACE.
TEMPERATURES WILL ALSO REMAIN RATHER WARM IN SATURDAY AS SOUTHWEST
WINDS AND GOOD INSOLATION BRING TEMPERATURES BACK INTO THE MID 60S.
JL
MID-RANGE FORECAST (SATURDAY NIGHT THROUGH MONDAY)
SATURDAY NIGHT...AN UPPER LEVEL TROUGH WILL MOVE EAST ACROSS THE
CENTRAL AND NORTHERN PLAINS. THE LOW-LEVELS OF THE ATMOSPHERE LOOK
DRY ENOUGH THAT NO MEASURABLE RAINFALL IS EXPECTED. HIGH AND MID
CLOUDS WILL INCREASE THROUGH THE NIGHT AND A WEAK COLD FRONT WILL
MOVE EASTWARD ACROSS THE CWA.
SUNDAY...LOOKS DRY WITH DECREASING CLOUDS THROUGH THE LATE MORNING
AND EARLY AFTERNOON HOURS. HIGHS WILL REACH THE MID 50S ALONG THE NE
BORDER TO THE LOWER 60S ACROSS EAST CENTRAL KS.
SUNDAY NIGHT AND MONDAY...ANOTHER H5 TROUGH WILL MOVE EAST ACROSS
THE PLAINS. DEEPER 850MB MOISTURE WILL BEGIN TO ADVECT NORTHWARD
BUT 850MB WINDS WILL VEER TO THE SOUTHWEST AS THE H5 TROUGH
APPROACHES THE PLAINS...AND WILL KEEP THE DEEPER MOISTURE SOUTH AND
EAST OF THE CWA. THERE MAY BE ENOUGH LOW AND MID LEVEL MOISTURE
ALONG WITH ASCENT AHEAD OF THE H5 TROUGH FOR SPRINKLES OR ISOLATED
SHOWERS ACROSS EAST CENTRAL KS SUNDAY NIGHT INTO MONDAY MORNING. THE
H5 TROUGH AXIS WILL MOVE ACROSS THE CWA MONDAY AFTERNOON...BRINGING
AN END TO ANY SPRINKLES OR SHOWERS. WESTERLY SURFACE WINDS WILL HELP
TO WARM HIGHS ON MONDAY INTO THE UPPER 50S TO LOWER 60S.
MONDAY NIGHT AND TUESDAY...AN H5 TROUGH WILL DIG SOUTHEAST FROM
WESTERN CANADA AND WILL AMPLIFY ACROSS THE UPPER MIDWEST. THIS WILL
CAUSE A COLD FRONT TO PUSH SOUTHWARD ACROSS THE CWA LATE MONDAY
NIGHT. LOW-LEVEL CAA WILL COOL HIGHS ON TUESDAY INTO THE LOWER TO
MID 50S.
GARGAN
EXTENDED FORECAST (MONDAY NIGHT THROUGH FRIDAY)
ALL MODELS ARE IN AGREEMENT THAT ZONAL UPPER LEVEL FLOW WILL SET UP
MONDAY NIGHT AND WILL CONTINUE FOR MUCH OF THE WORK WEEK. THE PATTERN
WILL KEEP CONDITIONS DRY AND TEMPERATURES NEAR NORMAL FOR THE
CENTRAL U.S DURING THE MIDDLE OF THE WEEK WITH HIGHS IN THE 50S
AND LOWS IN THE 30S.
MODELS ARE INDICATING THAT SURFACE HIGH PRESSURE WILL MOVE TO THE
EAST OF THE AREA ON WEDNESDAY WITH SOUTHERLY FLOW AND WARM AIR
ADVECTION RETURNING TO THE AREA ON THURSDAY. LEE CYCLOGENESIS WILL
TAKE PLACE ON THURSDAY AS AN UPPER LEVEL TROUGH MOVES ON SHORE.
MODELS ARE INDICATING A SHORTWAVE TROUGH WILL MOVE AHEAD OF THE MAIN
UPPER LEVEL TROUGH ON FRIDAY AND WILL MOVE THROUGH THE CENTRAL U.S.
BRINGING A CHANCE OF SHOWERS TO THE CWA. BEST MOISTURE RETURN WILL
BE OVER EASTERN PORTIONS OF THE CWA AND THIS IS WHERE PRECIPITATION
CHANCES WERE ADDED FOR FRIDAY.
ANDERSON
&&
.AVIATION...
EXPECT VFR CONDITIONS THROUGH NEXT 24 HOURS. WIND WILL GRADUALLY
PICK UP THROUGHOUT THE DAY THEN GO NEAR CALM OVERNIGHT. WINDS WILL
THEN INCREASE IN INTENSITY LATE IN THE FORECAST PERIOD WITH SOUTH-
SOUTHWEST WINDS AROUND 15 TO 25 KNOTS.
JL
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1112 PM CST THU NOV 10 2011
...AVIATION UPDATE...
.DISCUSSION...
SEE PREV DISCUSSION.
&&
.AVIATION...
THE LOW LEVEL JET IS PROGGED TO INCREASE AS THE NIGHT GOES ON. THIS
SHOULD KEEP THE TOP OF THE BOUNDARY LAYER MIXED AND PREVENT ANY FOG
OR STRATUS FROM FORMING. WITH THE BOUNDARY LAYER DECOUPLED...THINK
THIS WILL ALSO POSE A WIND SHEAR POTENTIAL AND WILL INCLUDE IN THE
FORECAST. OTHERWISE VFR CONDITIONS ARE EXPECTED GIVEN A DRY AIRMASS
AND WEAK IF ANY FORCING.
WOLTERS
&&
.PREV DISCUSSION... /239 PM CST THU NOV 10 2011/
TONIGHT AND FRIDAY...20Z WATER VAPOR IMAGERY AND RUC ANALYSIS
INDICATES THE STRONG 500 MB TROUGH WHICH BROUGHT THE AREA RAIN AND
SNOW HAS MOVED OFF TO THE EAST AND CURRENTLY SITS OVER THE GREAT
LAKES REGION. BEHIND THE DEPARTING WAVE LARGE SCALE SUBSIDENCE
REMAINS OVER THE FORECAST AREA BRINGING CLEAR SKIES. SURFACE
PRESSURE RIDGE WILL CONTINUE TO SLIDE EASTWARD...EVENTUALLY CAUSING
WINDS TO GRADUALLY SHIFT FROM W-NW TO W-SW DURING THE AFTERNOON
HOURS. CLEAR SKIES OVERNIGHT WILL ALLOW TEMPERATURES TO DROP RATHER
QUICKLY BACK INTO THE UPPER 20S TO LOWER 30S. WENT A LITTLE WARMER
WITH THE OVERNIGHT LOWS THAN THE PREVIOUS NIGHT AS LIGHT SOUTHERLY
FLOW SHOULD PERSIST ACROSS THE AREA AND MAY AID IN KEEPING THE LOWER
ATMOSPHERE BETTER MIXED. ANOTHER DAY OF CLEAR SKIES AND WARMER
TEMPERATURES IS ON TAP FOR FRIDAY AS THE LARGE SCALE SUBSIDENCE
PERSISTS OVER THE AREA. W-SW WINDS AND AMPLE INSOLATION SHOULD ALLOW
TEMPS TO WARM UP NICELY INTO THE LOWER TO MID 60S.
JL
FRIDAY NIGHT THROUGH SUNDAY EVENING...SURFACE HIGH SLIDES OFF
TO THE SOUTHEAST FRIDAY AFTERNOON WITH SURFACE RIDGING IN PLACE OVER
THE CWA FRIDAY EVENING. LEE SIDE LOW BEGINS TO INTENSIFY AS FAST
MOVING...ALMOST ALBERTA CLIPPER TYPE...UPPER LOW MOVES ESE FROM THE
CANADIAN PACIFIC COAST. WAA OCCURS OVER THE CWA FRIDAY NIGHT IN
RESPONSE TO THE LEE SIDE LOW DEVELOPMENT...AND 850 WINDS INCREASE TO
50KTS BY SATURDAY MORNING. LEE SIDE LOW IS ABSORBED INTO STRONGER
SURFACE LOW OVER SOUTHERN MANITOBA SATURDAY AFTERNOON. WITH THE
DECENT WAA...SHOULD SEE SURFACE TEMPS WELL INTO THE 60`S PERHAPS
EVEN LOW 70`S SATURDAY ALONG WITH BREEZY CONDITIONS. MIXING LOOKS
TO OCCUR TO AROUND 850MB, AND WITH VERY DRY AIR ADVECTING IN ALONG
WITH THE TEMPERATURES AT THAT LEVEL ALONG WITH GUSTY WINDS...COULD
SEE A FIRE DANGER BECOMING AN ISSUE FOR AREAS SOUTHEAST OF AN
ABILENE TO LAWRENCE LINE SATURDAY AFTERNOON. COLD FRONT EXPECTED TO
START TRAVERSING THE CWA BY 06Z SUNDAY...MOVING THROUGH TOP BY 09Z
AND EXITING THE CWA BY 12Z. THINKING IS THAT PREVIOUS OVERNIGHT
LOWS MAY HAVE BEEN A BIT HIGH WITH THE FRONT PUSHING THROUGH BY 09Z
ALONG AND MOISTURE BEING SCOURED OUT. BUMPED TEMPS DOWN ABOUT 5
DEGREES FOR MUCH OF THE CWA LEAVING ONLY THE FAR SOUTHEASTERN
COUNTIES A BIT WARMER. CAA WILL BE SHORT LIVED AS NEXT UPPER WAVE
REDEVELOPS LEE SIDE TROUGH AND WAA ONCE AGAIN OCCURS SUNDAY
AFTERNOON/EVENING.
SUNDAY NIGHT THROUGH THURSDAY...THE FORECAST CHALLENGE IN THE
EXTENDED WILL BE THE CHANCES FOR PRECIPITATION ON SUNDAY NIGHT INTO
MONDAY. THE UPPER LEVEL WAVE THAT COULD BRING PRECIPITATION TO THE
AREA IS CURRENTLY LOCATED OFF THE PACIFIC COAST. MODELS DIFFER
CONSIDERABLY ON HOW THIS WAVE WILL EVOLVE AND EFFECT THE CENTRAL
U.S. EARLY NEXT WEEK. THE GFS ALONG WITH MANY OF THE ENSEMBLE
MEMBERS HAVE THE UPPER LEVEL WAVE CLOSING OFF AND REMAINING WELL TO
THE SOUTH OF THE AREA. THE ECMWF SHOWS A MORE PROGRESS OPEN UPPER
LEVEL TROUGH MOVING THROUGH THE CENTRAL U.S. THIS SOLUTION WOULD
BRING A CHANCE FOR SHOWERS TO THE CWA. THE ECMWF INDICATES BEST
MOISTURE RETURN AND LIFT WILL BE OVER SOUTHERN AND EASTERN PORTIONS
OF THE CWA. THE GEM IS MORE IN LINE WITH THE ECMWF WITH AN OPEN WAVE
TROUGH MOVING THROUGH THE CENTRAL U.S. ON SUNDAY NIGHT INTO MONDAY.
CLEARLY...UNCERTAINTY EXIST IN THE MODEL SOLUTIONS AND HAVE INCLUDED
SLIGHT CHANCE POPS SUNDAY NIGHT INTO MONDAY WITH AN EMPHASIS OVER
SOUTHERN AND EASTERN PORTIONS OF THE CWA.
ALL MODELS ARE DEPICTING ZONAL UPPER LEVEL FLOW FOR THE MIDDLE OF
NEXT WEEK. THE PATTERN WILL KEEP THE FORECAST DRY WITH NEAR NORMAL
TEMPERATURES ACROSS THE CWA.
ANDERSON
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
502 PM CST THU NOV 10 2011
...AVIATION UPDATE...
.DISCUSSION...
SEE PREV DISCUSSION.
&&
.AVIATION...
A SFC TROUGH OVER THE HIGH PLAINS SHOULD MOVE ACROSS THE STATE
OVERNIGHT. THIS IS EXPECTED TO KEEP THE BOUNDARY LAYER MIXED THROUGH
THE NIGHT DUE TO AN INCREASING PRESSURE GRADIENT. ADDITIONALLY
OBJECTIVE GUIDANCE ONLY SHOW A VERY LOW PROB OF GROUND FOG OR
STRATUS DEVELOPING. THEREFORE WILL CONTINUE WITH A VFR FORECAST AND
MONITOR AXIS OF HIGHER DEWPOINTS ACROSS CENTRAL KS FOR FOG OR
STRATUS DEVELOPMENT. WILL ALSO NEED TO KEEP AN EYE ON THE LOW LEVEL
JET FOR POTENTIAL WIND SHEAR LATER TONIGHT.
WOLTERS
&&
.PREV DISCUSSION... /239 PM CST THU NOV 10 2011/
TONIGHT AND FRIDAY...20Z WATER VAPOR IMAGERY AND RUC ANALYSIS
INDICATES THE STRONG 500 MB TROUGH WHICH BROUGHT THE AREA RAIN AND
SNOW HAS MOVED OFF TO THE EAST AND CURRENTLY SITS OVER THE GREAT
LAKES REGION. BEHIND THE DEPARTING WAVE LARGE SCALE SUBSIDENCE
REMAINS OVER THE FORECAST AREA BRINGING CLEAR SKIES. SURFACE
PRESSURE RIDGE WILL CONTINUE TO SLIDE EASTWARD...EVENTUALLY CAUSING
WINDS TO GRADUALLY SHIFT FROM W-NW TO W-SW DURING THE AFTERNOON
HOURS. CLEAR SKIES OVERNIGHT WILL ALLOW TEMPERATURES TO DROP RATHER
QUICKLY BACK INTO THE UPPER 20S TO LOWER 30S. WENT A LITTLE WARMER
WITH THE OVERNIGHT LOWS THAN THE PREVIOUS NIGHT AS LIGHT SOUTHERLY
FLOW SHOULD PERSIST ACROSS THE AREA AND MAY AID IN KEEPING THE LOWER
ATMOSPHERE BETTER MIXED. ANOTHER DAY OF CLEAR SKIES AND WARMER
TEMPERATURES IS ON TAP FOR FRIDAY AS THE LARGE SCALE SUBSIDENCE
PERSISTS OVER THE AREA. W-SW WINDS AND AMPLE INSOLATION SHOULD ALLOW
TEMPS TO WARM UP NICELY INTO THE LOWER TO MID 60S.
JL
FRIDAY NIGHT THROUGH SUNDAY EVENING...SURFACE HIGH SLIDES OFF
TO THE SOUTHEAST FRIDAY AFTERNOON WITH SURFACE RIDGING IN PLACE OVER
THE CWA FRIDAY EVENING. LEE SIDE LOW BEGINS TO INTENSIFY AS FAST
MOVING...ALMOST ALBERTA CLIPPER TYPE...UPPER LOW MOVES ESE FROM THE
CANADIAN PACIFIC COAST. WAA OCCURS OVER THE CWA FRIDAY NIGHT IN
RESPONSE TO THE LEE SIDE LOW DEVELOPMENT...AND 850 WINDS INCREASE TO
50KTS BY SATURDAY MORNING. LEE SIDE LOW IS ABSORBED INTO STRONGER
SURFACE LOW OVER SOUTHERN MANITOBA SATURDAY AFTERNOON. WITH THE
DECENT WAA...SHOULD SEE SURFACE TEMPS WELL INTO THE 60`S PERHAPS
EVEN LOW 70`S SATURDAY ALONG WITH BREEZY CONDITIONS. MIXING LOOKS
TO OCCUR TO AROUND 850MB, AND WITH VERY DRY AIR ADVECTING IN ALONG
WITH THE TEMPERATURES AT THAT LEVEL ALONG WITH GUSTY WINDS...COULD
SEE A FIRE DANGER BECOMING AN ISSUE FOR AREAS SOUTHEAST OF AN
ABILENE TO LAWRENCE LINE SATURDAY AFTERNOON. COLD FRONT EXPECTED TO
START TRAVERSING THE CWA BY 06Z SUNDAY...MOVING THROUGH TOP BY 09Z
AND EXITING THE CWA BY 12Z. THINKING IS THAT PREVIOUS OVERNIGHT
LOWS MAY HAVE BEEN A BIT HIGH WITH THE FRONT PUSHING THROUGH BY 09Z
ALONG AND MOISTURE BEING SCOURED OUT. BUMPED TEMPS DOWN ABOUT 5
DEGREES FOR MUCH OF THE CWA LEAVING ONLY THE FAR SOUTHEASTERN
COUNTIES A BIT WARMER. CAA WILL BE SHORT LIVED AS NEXT UPPER WAVE
REDEVELOPS LEE SIDE TROUGH AND WAA ONCE AGAIN OCCURS SUNDAY
AFTERNOON/EVENING.
SUNDAY NIGHT THROUGH THURSDAY...THE FORECAST CHALLENGE IN THE
EXTENDED WILL BE THE CHANCES FOR PRECIPITATION ON SUNDAY NIGHT INTO
MONDAY. THE UPPER LEVEL WAVE THAT COULD BRING PRECIPITATION TO THE
AREA IS CURRENTLY LOCATED OFF THE PACIFIC COAST. MODELS DIFFER
CONSIDERABLY ON HOW THIS WAVE WILL EVOLVE AND EFFECT THE CENTRAL
U.S. EARLY NEXT WEEK. THE GFS ALONG WITH MANY OF THE ENSEMBLE
MEMBERS HAVE THE UPPER LEVEL WAVE CLOSING OFF AND REMAINING WELL TO
THE SOUTH OF THE AREA. THE ECMWF SHOWS A MORE PROGRESS OPEN UPPER
LEVEL TROUGH MOVING THROUGH THE CENTRAL U.S. THIS SOLUTION WOULD
BRING A CHANCE FOR SHOWERS TO THE CWA. THE ECMWF INDICATES BEST
MOISTURE RETURN AND LIFT WILL BE OVER SOUTHERN AND EASTERN PORTIONS
OF THE CWA. THE GEM IS MORE IN LINE WITH THE ECMWF WITH AN OPEN WAVE
TROUGH MOVING THROUGH THE CENTRAL U.S. ON SUNDAY NIGHT INTO MONDAY.
CLEARLY...UNCERTAINTY EXIST IN THE MODEL SOLUTIONS AND HAVE INCLUDED
SLIGHT CHANCE POPS SUNDAY NIGHT INTO MONDAY WITH AN EMPHASIS OVER
SOUTHERN AND EASTERN PORTIONS OF THE CWA.
ALL MODELS ARE DEPICTING ZONAL UPPER LEVEL FLOW FOR THE MIDDLE OF
NEXT WEEK. THE PATTERN WILL KEEP THE FORECAST DRY WITH NEAR NORMAL
TEMPERATURES ACROSS THE CWA.
ANDERSON
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
THE PREVIOUS SHORT TERM FORECAST DISCUSSION FOLLOWS...
/TODAY THROUGH MONDAY/
SFC ANALYSIS THIS MORNING SHOWS HIGH PRESSURE DOMINATING THE SERN
U.S. WITH A STOUT PRESSURE GRADIENT OVER THE OH/TN VALLEYS. THIS HAS
INDUCED A GOOD SWLY RETURN FLOW FROM THE GOMEX...RUNNING UP THE LOWER
MS VALLEY ALL THE WAY UP INTO THE GREAT LAKES AND SETTING UP A GOOD
RIDGE VALLEY SPLIT LOCALLY...WITH THE RIDGES RUNNING IN THE MID 40S
WHILE THE MOST DECOUPLED VALLEYS HAVE DROPPED OFF INTO THE UPPER 20S.
HIGH PRESSURE LOOKS TO CONTINUE DOMINATING THE LOCAL WEATHER FOR THE
NEXT 24 TO 36 HOURS BUT WILL SLOWLY EASE TOWARDS THE MID ATLANTIC
COAST BY SUNDAY NIGHT...MAKING ROOM FOR AN APPROACHING COLD FRONT
TIED TO A DEEPENING LOW PRESSURE SYSTEM SKIRTING THE U.S./CANADIAN
BORDER. THIS FRONT IS EXPECTED TO STALL SOMEWHERE IN THE VICINITY OF
THE OH VALLEY AROUND THE SUNDAY NIGHT/MONDAY TIME FRAME...AND SHOULD
BECOME THE FOCUS FOR WIDESPREAD SHOWERS BY MONDAY...BUT MODELS ARE
STILL SHOWING A BIT OF A SPREAD WITH REGARDS TO THE LOCATION AND
ORIENTATION OF THE BOUNDARY IN QUESTION LATE IN THE PERIOD.
THE 12.00Z GFS LEADS THE PACK IN TIMING AND STRENGTH OF A SFC WAVE
ORIGINATING OVER THE SRN PLAINS AND RIDING UP ALONG THE BOUNDARY BY
SUNDAY NIGHT INTO MONDAY...THOUGH APPEARS TO SUPPORT THE POSITION OF
THE FRONT AS DEPICTED IN THE 00Z NAM. MEANWHILE...THE 12.00Z ECMWF
HAS TRENDED SLIGHTLY WEAKER WITH THE FORCING ASSOCIATED WITH THE
SFC WAVE AND KEEPS THE BULK OF THE PRECIP ASSOCIATED WITH THE WAVE
FURTHER NORTH THAN AS SEEN IN ITS PREDECESSOR. OVERALL...THE MODEL
CONSENSUS APPEARS TO BE TRENDING SLOWER WITH THE ONSET OF THE EFFECTS
OF THIS FEATURE AND HAVE TRENDED THE FORECAST IN THIS DIRECTION AS
WELL.
SENSIBLE WEATHER WILL FEATURE ANOTHER BRIGHT...SUNSHINE FILLED DAY
WITH TEMPS REBOUNDING INTO THE LOWER 60S THIS AFTERNOON. CLEAR SKIES
AGAIN TONIGHT SHOULD YIELD ANOTHER MODEST...THOUGH WARMER RIDGE/VALLEY
TEMP SPLIT WITH THE SHELTERED VALLEYS DROPPING INTO THE LOWER TO MID
30S WHILE THE RIDGES AND BROADER VALLEYS SETTLE IN THE MID TO UPPER
40S. SUNDAY SHOULD SEE ANOTHER BUMP IN TEMPS WITH THE STRENGTHENING
WAA PATTERN SENDING THE MERCURY INTO THE MID TO UPPER 60S.
SUNDAY NIGHT WILL BEGIN TO SEE MID AND UPPER LEVEL CLOUDS INCREASING
ALONG THE OH VALLEY AS THE FRONT APPROACHES AND...ALTHOUGH POPS WERE
TRIMMED...HAVE KEPT A SLIGHT CHANCE OF SHOWERS IN AND AROUND THE
BLUEGRASS COUNTIES. POPS SHOULD BEGIN TO INCREASE FROM NW TO SE THRU
THE DAY ON MONDAY AS THE FRONT BECOMES MORE ACTIVE IN RESPONSE TO AN
APPROACHING SRN STREAM TROF LIFTING OUT OF THE SRN PLAINS...PER CURRENT
MODEL CONSENSUS. HAVE GENERALLY STAYED BELOW GUIDANCE FOR HIGHS ON
MONDAY AS THE INHERITED MID TO UPPER 60S LOOKED MORE REASONABLE.
.LONG TERM.../MONDAY NIGHT THROUGH FRIDAY/
12/00Z MODEL RUNS CONTINUE TO COME INTO BETTER AGREEMENT REGARDING
THE EVOLUTION OF A LONGWAVE TROUGH WHICH STARTS OUT ALIGNED OVER THE
CENTRAL PLAINS TO START THE PERIOD. IN PARTICULAR...PROGS ARE IN
MUCH BETTER AGREEMENT TONIGHT THAT A CLOSED LOW NOW LOCATED OFF THE
COAST OF CALIFORNIA WILL GET ABSORBED INTO THE MEAN TROUGH AND NOT
HANG BACK AS PROJECTED IN EARLIER RUNS. THIS RESULTS IN A QUICKER
EXIT TO ANY PRECIPITATION ASSOCIATED WITH OUR EARLY WEEK SYSTEM.
PROGS THEN ALL INDICATE ZONAL FLOW DEVELOPS BY MIDWEEK...WITH HINTS
OF SOME FLAT RIDGING TAKING OVER BY THE END OF THE PERIOD.
THE CONSENSUS MODEL STARTING POINT HAD GOOD CONTINUITY WITH THE
INHERITED FORECAST AND FEW CHANGES WILL BE NOTICED WITH THIS UPDATE.
A COLD FRONT IS EXPECTED TO PASS THROUGH THE REGION LATE MONDAY
NIGHT AND TUESDAY MORNING...WITH LIKELY RAIN CHANCES ADVERTISED. THE
SHOWERS MAY BE SLOW TO OVERSPREAD THE AREA MONDAY NIGHT THOUGH WITH
A STIFF SOUTHERLY DOWNSLOPE FLOW IN PLACE PRIOR TO THE FRONTAL
PASSAGE. DUE TO THE SPEED OF THE SYSTEM...AND EARLY OCCURRENCE OF
DOWNSLOPE DRYING...RAINFALL AMOUNTS ARE EXPECTED TO REMAIN LESS THAN
AN INCH. WILL THEN CARRY OVER SOME LOW CHANCE POPS FOR MUCH OF THE
AREA ON TUESDAY EVENING...BUT SKIES SHOULD CLEAR OVERNIGHT AS SURFACE
HIGH PRESSURE BUILDS IN. PROGS THEN SHOW ANOTHER WEAK FRONT PASSING
THROUGH TUESDAY NIGHT OR WEDNESDAY...BUT WITHOUT MUCH FANFARE AND
WILL KEEP WITH A DRY FORECAST. HIGH PRESSURE IS THEN PROGGED TO
OVERSPREAD THE EASTERN U.S. TO END THE WORK WEEK. EARLIER ECMWF RUNS
INDICATED A QUICK RETURN FLOW SET UP BY FRIDAY BUT THE 12/00Z RUN
BACKED OFF THIS SCENARIO AND WE WILL KEEP THE FORECAST DRY.
TEMPERATURES WILL BE NEAR NORMAL THROUGH THE PERIOD. DAYTIME HIGHS
WILL GET KNOCKED BACK FROM THE 60S ON TUESDAY TO THE MID TO UPPER
50S WEDNESDAY AND THURSDAY. OVERNIGHT LOWS WILL DROP FROM THE 50S
MONDAY NIGHT TO THE 40S ON TUESDAY NIGHT. DRIER AIR BEHIND THE WEAK
MIDWEEK FRONTAL PASSAGE WILL THEN ALLOW LOWS TO DIP INTO THE 30S FOR
THE REST OF THE PERIOD...WITH SOME 20S POSSIBLE IN OUR COLDER
VALLEYS.
&&
.AVIATION.../12Z TO 12Z/
STRONG S TO SW WINDS WILL BE THE ONLY ISSUE FOR THE PERIOD AS HIGH
PRESSURE OVER THE SERN CONUS EXPANDS ITS INFLUENCE FURTHER INTO THE
AREA TODAY...WITH SUSTAINED WINDS AROUND 10 TO 15 KTS AND GUSTS
AROUND 20 TO 25 KTS DEVELOPING THIS MORNING AND CONTINUING THROUGH
THE LATE AFTERNOON BEFORE SLACKENING LATER THIS EVENING. RUC AND NAM
FORECAST SOUNDINGS SUGGEST A STRONG LOW LEVEL JET PRESENT AT ISSUANCE
BETWEEN 1.0 TO 1.5 KFT AGL AROUND 40KTS...AND HAVE CONTINUED TO
ADVERTISE LLWS IN THE TAFS THROUGH THE MORNING BEFORE SFC WINDS
ENGAGE AS WELL. OTHERWISE...VFR CONDITIONS LOOK TO PREVAIL THROUGH
THE REMAINDER OF THE WEEKEND.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...MB/GEOGERIAN
LONG TERM....ABE
AVIATION...MB
AREA FORECAST DISCUSSION
NWS JACKSON KY
635 AM EST SAT NOV 12 2011
.SHORT TERM.../TODAY THROUGH MONDAY/
SFC ANALYSIS THIS MORNING SHOWS HIGH PRESSURE DOMINATING THE SERN
U.S. WITH A STOUT PRESSURE GRADIENT OVER THE OH/TN VALLEYS. THIS HAS
INDUCED A GOOD SWLY RETURN FLOW FROM THE GOMEX...RUNNING UP THE LOWER
MS VALLEY ALL THE WAY UP INTO THE GREAT LAKES AND SETTING UP A GOOD
RIDGE VALLEY SPLIT LOCALLY...WITH THE RIDGES RUNNING IN THE MID 40S
WHILE THE MOST DECOUPLED VALLEYS HAVE DROPPED OFF INTO THE UPPER 20S.
HIGH PRESSURE LOOKS TO CONTINUE DOMINATING THE LOCAL WEATHER FOR THE
NEXT 24 TO 36 HOURS BUT WILL SLOWLY EASE TOWARDS THE MID ATLANTIC
COAST BY SUNDAY NIGHT...MAKING ROOM FOR AN APPROACHING COLD FRONT
TIED TO A DEEPENING LOW PRESSURE SYSTEM SKIRTING THE U.S./CANADIAN
BORDER. THIS FRONT IS EXPECTED TO STALL SOMEWHERE IN THE VICINITY OF
THE OH VALLEY AROUND THE SUNDAY NIGHT/MONDAY TIME FRAME...AND SHOULD
BECOME THE FOCUS FOR WIDESPREAD SHOWERS BY MONDAY...BUT MODELS ARE
STILL SHOWING A BIT OF A SPREAD WITH REGARDS TO THE LOCATION AND
ORIENTATION OF THE BOUNDARY IN QUESTION LATE IN THE PERIOD.
THE 12.00Z GFS LEADS THE PACK IN TIMING AND STRENGTH OF A SFC WAVE
ORIGINATING OVER THE SRN PLAINS AND RIDING UP ALONG THE BOUNDARY BY
SUNDAY NIGHT INTO MONDAY...THOUGH APPEARS TO SUPPORT THE POSITION OF
THE FRONT AS DEPICTED IN THE 00Z NAM. MEANWHILE...THE 12.00Z ECMWF
HAS TRENDED SLIGHTLY WEAKER WITH THE FORCING ASSOCIATED WITH THE
SFC WAVE AND KEEPS THE BULK OF THE PRECIP ASSOCIATED WITH THE WAVE
FURTHER NORTH THAN AS SEEN IN ITS PREDECESSOR. OVERALL...THE MODEL
CONSENSUS APPEARS TO BE TRENDING SLOWER WITH THE ONSET OF THE EFFECTS
OF THIS FEATURE AND HAVE TRENDED THE FORECAST IN THIS DIRECTION AS
WELL.
SENSIBLE WEATHER WILL FEATURE ANOTHER BRIGHT...SUNSHINE FILLED DAY
WITH TEMPS REBOUNDING INTO THE LOWER 60S THIS AFTERNOON. CLEAR SKIES
AGAIN TONIGHT SHOULD YIELD ANOTHER MODEST...THOUGH WARMER RIDGE/VALLEY
TEMP SPLIT WITH THE SHELTERED VALLEYS DROPPING INTO THE LOWER TO MID
30S WHILE THE RIDGES AND BROADER VALLEYS SETTLE IN THE MID TO UPPER
40S. SUNDAY SHOULD SEE ANOTHER BUMP IN TEMPS WITH THE STRENGTHENING
WAA PATTERN SENDING THE MERCURY INTO THE MID TO UPPER 60S.
SUNDAY NIGHT WILL BEGIN TO SEE MID AND UPPER LEVEL CLOUDS INCREASING
ALONG THE OH VALLEY AS THE FRONT APPROACHES AND...ALTHOUGH POPS WERE
TRIMMED...HAVE KEPT A SLIGHT CHANCE OF SHOWERS IN AND AROUND THE
BLUEGRASS COUNTIES. POPS SHOULD BEGIN TO INCREASE FROM NW TO SE THRU
THE DAY ON MONDAY AS THE FRONT BECOMES MORE ACTIVE IN RESPONSE TO AN
APPROACHING SRN STREAM TROF LIFTING OUT OF THE SRN PLAINS...PER CURRENT
MODEL CONSENSUS. HAVE GENERALLY STAYED BELOW GUIDANCE FOR HIGHS ON
MONDAY AS THE INHERITED MID TO UPPER 60S LOOKED MORE REASONABLE.
.LONG TERM.../MONDAY NIGHT THROUGH FRIDAY/
12/00Z MODEL RUNS CONTINUE TO COME INTO BETTER AGREEMENT REGARDING
THE EVOLUTION OF A LONGWAVE TROUGH WHICH STARTS OUT ALIGNED OVER THE
CENTRAL PLAINS TO START THE PERIOD. IN PARTICULAR...PROGS ARE IN
MUCH BETTER AGREEMENT TONIGHT THAT A CLOSED LOW NOW LOCATED OFF THE
COAST OF CALIFORNIA WILL GET ABSORBED INTO THE MEAN TROUGH AND NOT
HANG BACK AS PROJECTED IN EARLIER RUNS. THIS RESULTS IN A QUICKER
EXIT TO ANY PRECIPITATION ASSOCIATED WITH OUR EARLY WEEK SYSTEM.
PROGS THEN ALL INDICATE ZONAL FLOW DEVELOPS BY MIDWEEK...WITH HINTS
OF SOME FLAT RIDGING TAKING OVER BY THE END OF THE PERIOD.
THE CONSENSUS MODEL STARTING POINT HAD GOOD CONTINUITY WITH THE
INHERITED FORECAST AND FEW CHANGES WILL BE NOTICED WITH THIS UPDATE.
A COLD FRONT IS EXPECTED TO PASS THROUGH THE REGION LATE MONDAY
NIGHT AND TUESDAY MORNING...WITH LIKELY RAIN CHANCES ADVERTISED. THE
SHOWERS MAY BE SLOW TO OVERSPREAD THE AREA MONDAY NIGHT THOUGH WITH
A STIFF SOUTHERLY DOWNSLOPE FLOW IN PLACE PRIOR TO THE FRONTAL
PASSAGE. DUE TO THE SPEED OF THE SYSTEM...AND EARLY OCCURRENCE OF
DOWNSLOPE DRYING...RAINFALL AMOUNTS ARE EXPECTED TO REMAIN LESS THAN
AN INCH. WILL THEN CARRY OVER SOME LOW CHANCE POPS FOR MUCH OF THE
AREA ON TUESDAY EVENING...BUT SKIES SHOULD CLEAR OVERNIGHT AS SURFACE
HIGH PRESSURE BUILDS IN. PROGS THEN SHOW ANOTHER WEAK FRONT PASSING
THROUGH TUESDAY NIGHT OR WEDNESDAY...BUT WITHOUT MUCH FANFARE AND
WILL KEEP WITH A DRY FORECAST. HIGH PRESSURE IS THEN PROGGED TO
OVERSPREAD THE EASTERN U.S. TO END THE WORK WEEK. EARLIER ECMWF RUNS
INDICATED A QUICK RETURN FLOW SET UP BY FRIDAY BUT THE 12/00Z RUN
BACKED OFF THIS SCENARIO AND WE WILL KEEP THE FORECAST DRY.
TEMPERATURES WILL BE NEAR NORMAL THROUGH THE PERIOD. DAYTIME HIGHS
WILL GET KNOCKED BACK FROM THE 60S ON TUESDAY TO THE MID TO UPPER
50S WEDNESDAY AND THURSDAY. OVERNIGHT LOWS WILL DROP FROM THE 50S
MONDAY NIGHT TO THE 40S ON TUESDAY NIGHT. DRIER AIR BEHIND THE WEAK
MIDWEEK FRONTAL PASSAGE WILL THEN ALLOW LOWS TO DIP INTO THE 30S FOR
THE REST OF THE PERIOD...WITH SOME 20S POSSIBLE IN OUR COLDER
VALLEYS.
&&
.AVIATION.../12Z TO 12Z/...UPDATED
STRONG S TO SW WINDS WILL BE THE ONLY ISSUE FOR THE PERIOD AS HIGH
PRESSURE OVER THE SERN CONUS EXPANDS ITS INFLUENCE FURTHER INTO THE
AREA TODAY...WITH SUSTAINED WINDS AROUND 10 TO 15 KTS AND GUSTS
AROUND 20 TO 25 KTS DEVELOPING THIS MORNING AND CONTINUING THROUGH
THE LATE AFTERNOON BEFORE SLACKENING LATER THIS EVENING. RUC AND NAM
FORECAST SOUNDINGS SUGGEST A STRONG LOW LEVEL JET PRESENT AT ISSUANCE
BETWEEN 1.0 TO 1.5 KFT AGL AROUND 40KTS...AND HAVE CONTINUED TO
ADVERTISE LLWS IN THE TAFS THROUGH THE MORNING BEFORE SFC WINDS
ENGAGE AS WELL. OTHERWISE...VFR CONDITIONS LOOK TO PREVAIL THROUGH
THE REMAINDER OF THE WEEKEND.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...MB
LONG TERM....ABE
AVIATION...MB
AREA FORECAST DISCUSSION
NWS CARIBOU ME
508 PM EST SAT NOV 12 2011
.SYNOPSIS...
A HIGH PRESSURE RIDGE WILL BUILD ACROSS THE REGION TONIGHT AND
THEN MOVE EAST OF THE AREA SUNDAY AND MONDAY.&&
.NEAR TERM /THROUGH SUNDAY/...
UPDATE: MINOR ADJUSTMENT TO POPS ACROSS THE N/PRECIP TYPE AND HRLY TEMPS...
SHORTWAVE TROUGH JUST WEST OF THE
REGION THIS AFTERNOON WILL CROSS THE STATE BY EARLY THIS EVENING.
SAT IMG INDICATES OVERCAST SKIES ACROSS MOST OF NORTHERN AND
CENTRAL SECTIONS WITH A MIX OF SUN AND CLOUDS ACROSS DOWNEAST THIS
AFTERNOON. RH PROGS INDICATE CLOUDS TO REMAIN ACROSS MOST OF
NORTHERN AND CENTRAL SECTIONS INTO EARLY THIS EVENING THEN
GRADUALLY CLEARING THE REMAINDER OF THE NIGHT WITH THE TROUGH
PASSAGE. CLOUDS WILL DISSIPATE ACROSS DOWNEAST BY EARLY THIS
EVENING. RADAR INDICATING SCATTERED SNOW SHOWERS/FLURRIES HAVE
DEVELOPED ACROSS NORTHERN AND CENTRAL SECTIONS. HRRR AND RUC
MODELS INDICATE THIS ACTIVITY WILL CONTINUE UNTIL UPPER TROUGH
MOVES EAST OF THE REGION EARLY THIS EVENING.
UPPER RIDGE CRESTS THE STATE EARLY SUNDAY MORNING AND THEN MOVES
EAST OF THE REGION BY NOONTIME. SOUTHWEST FLOW ON THE BACKSIDE OF
THE RIDGE WILL ALLOW WARM AIR ADVECTION TO OCCUR ACROSS THE STATE
WITH TEMPERATURES MODERATING INTO THE MID TO UPPER 40S ACROSS THE
NORTH AND THE 50S ACROSS DOWNEAST.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
UNSETTLED WEATHER IS EXPECTED THROUGH THE SHORT TERM PERIOD AS A
SERIES OF WAVES MOVES THROUGH SOUTHWEST FLOW ALOFT. THE FIRST WILL
COME SUNDAY NIGHT AND WILL REMAIN TO OUR NORTH AND WEST. IT WILL BE
ENOUGH TO FIRE UP SOME SHOWERS ACROSS NORTHERN MAINE THROUGH EARLY
MONDAY AFTERNOON. THE NEXT GOOD CHANCE OF PRECIPITATION ARRIVES
MONDAY NIGHT WITH YET ANOTHER WEAK IMPULSE TO TRAVERSE ACROSS THE
REGION. BRIEF RIDGING WILL BUILD OVER NORTHERN NEW ENGLAND IN ITS
WAKE...SO EXPECT THERE WILL BE A BRIEF DRY SPELL TUESDAY BEFORE A
STRONGER SYSTEM APPROACHES FROM THE WEST. RAIN FROM THIS FINAL WAVE
WILL SPREAD INTO MAINLY SOUTHERN SECTIONS OF THE FORECAST AREA LATE
TUESDAY AFTERNOON. THE UPSIDE OF ALL THESE SHORTWAVES WILL BE MILD
TEMPERATURES AS THEY LOOK TO STAY FAR ENOUGH NORTH THAT WE WILL STAY
OUT OF THE COLD AIR. DAYTIME HIGHS WILL RANGE FROM AROUND 50 NORTH
TO THE UPPER 50S DOWNEAST...AND OVERNIGHT LOWS IN THE 40S DUE TO
CLOUD COVER.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
RAIN SHOULD BE SPREADING NORTHWARD ON TUESDAY NIGHT IN RESPONSE TO
A LOW PRESSURE SYSTEM MOVING ALONG THE COAST OF MAINE. THERE ARE
STILL SOME DIFFERENCES IN THE GFS AND ECMWF IN THIS TIME FRAME.
THE GFS WANTS TO BRING THE LOW THROUGH ON TUESDAY NIGHT INTO
WEDNESDAY...ON THE OTHER HAND IT SEEMS AS IF THE ECMWF IS ABOUT 18
TO 24 HOURS SLOWER. WILL LEAN WITH GFS WITH THIS PACKAGE. RAIN
SHOULD END LATE WEDNESDAY EVENING. HIGH PRESSURE THEN MOVES IN FOR
THURSDAY THROUGH FRIDAY EVENING BEFORE A WEAK SYSTEM PASSES OFF TO
THE NORTH BRINGING A SLIGHT CHANCE OF PRECIP. TEMPERATURES AFTER
THE STORM WEDNESDAY WILL RETURN TO NORMAL NOVEMBER AVERAGES
THROUGH SATURDAY. USED A BLEND OF GMOS AND GFS FOR THE PERIOD AND
ADJUSTED AS NEEDED.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
NEAR TERM: VFR CONDITIONS TONIGHT AND SUNDAY. FLURRIES POSSIBLE
ACROSS NORTHERN TERMINALS INTO EARLY THIS EVENING BUT SHOULD NOT
RESTRICT VSBY.
SHORT TERM: VFR WITH PERIODS OF MVFR IN RAIN SHOWERS EXPECTED
THROUGH THE PERIOD.
&&
.MARINE...
NEAR TERM: SCA WINDS AND SEAS CONTINUE ACROSS THE WATERS THIS
EVENING AND THEN EXPECT WINDS TO DROP BELOW SCA CRITERIA AFTER
MIDNIGHT. HOWEVER, SEAS ABOVE 5 FEET DUE TO SWELL WILL CONTINUE
THROUGH THE NIGHT SO WILL KEEP SCA GOING FOR THE ENTIRE NIGHT.
SHORT TERM: SOUTHWEST WINDS OF 15 TO 25 KT ARE EXPECTED SUNDAY
NIGHT AND MONDAY AS LOW PRESSURE SKIRTS BY TO THE NORTH OF THE
WATERS. A SMALL CRAFT ADVISORY WILL PROBABLY BE NEEDED...FOR WAVES
AS WELL AS WINDS. CONDITIONS WILL SUBSIDE MONDAY NIGHT BUT WILL
INCREASE TO CLOSE TO SCA CRITERIA AGAIN TUESDAY AHEAD OF ANOTHER
LOW PRESSURE SYSTEM.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ050>052.
&&
$$
NEAR TERM...KHW/FOSTER
SHORT TERM...HASTINGS
LONG TERM...HILL
AVIATION...KHW/FOSTER
MARINE...KHW/FOSTER/HASTINGS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
302 PM EST SAT NOV 12 2011
.SYNOPSIS...
A HIGH PRESSURE RIDGE WILL BUILD ACROSS THE REGION TONIGHT AND
THEN MOVE EAST OF THE AREA SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
SHORTWAVE TROUGH JUST WEST OF THE REGION THIS AFTERNOON WILL
CROSS THE STATE BY EARLY THIS EVENING. SAT IMG INDICATES OVERCAST
SKIES ACROSS MOST OF NORTHERN AND CENTRAL SECTIONS WITH A MIX OF
SUN AND CLOUDS ACROSS DOWNEAST THIS AFTERNOON. RH PROGS INDICATE
CLOUDS TO REMAIN ACROSS MOST OF NORTHERN AND CENTRAL SECTIONS INTO
EARLY THIS EVENING THEN GRADUALLY CLEARING THE REMAINDER OF THE
NIGHT WITH THE TROUGH PASSAGE. CLOUDS WILL DISSIPATE ACROSS DOWNEAST
BY EARLY THIS EVENING. RADAR INDICATING SCATTERED SNOW
SHOWERS/FLURRIES HAVE DEVELOPED ACROSS NORTHERN AND CENTRAL
SECTIONS. HRRR AND RUC MODELS INDICATE THIS ACTIVITY WILL CONTINUE
UNTIL UPPER TROUGH MOVES EAST OF THE REGION EARLY THIS EVENING.
UPPER RIDGE CRESTS THE STATE EARLY SUNDAY MORNING AND THEN MOVES
EAST OF THE REGION BY NOONTIME. SOUTHWEST FLOW ON THE BACKSIDE OF
THE RIDGE WILL ALLOW WARM AIR ADVECTION TO OCCUR ACROSS THE STATE
WITH TEMPERATURES MODERATING INTO THE MID TO UPPER 40S ACROSS THE
NORTH AND THE 50S ACROSS DOWNEAST.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
UNSETTLED WEATHER IS EXPECTED THROUGH THE SHORT TERM PERIOD AS A
SERIES OF WAVES MOVES THROUGH SOUTHWEST FLOW ALOFT. THE FIRST WILL
COME SUNDAY NIGHT AND WILL REMAIN TO OUR NORTH AND WEST. IT WILL BE
ENOUGH TO FIRE UP SOME SHOWERS ACROSS NORTHERN MAINE THROUGH EARLY
MONDAY AFTERNOON. THE NEXT GOOD CHANCE OF PRECIPITATION ARRIVES
MONDAY NIGHT WITH YET ANOTHER WEAK IMPULSE TO TRAVERSE ACROSS THE
REGION. BRIEF RIDGING WILL BUILD OVER NORTHERN NEW ENGLAND IN ITS
WAKE...SO EXPECT THERE WILL BE A BRIEF DRY SPELL TUESDAY BEFORE A
STRONGER SYSTEM APPROACHES FROM THE WEST. RAIN FROM THIS FINAL WAVE
WILL SPREAD INTO MAINLY SOUTHERN SECTIONS OF THE FORECAST AREA LATE
TUESDAY AFTERNOON. THE UPSIDE OF ALL THESE SHORTWAVES WILL BE MILD
TEMPERATURES AS THEY LOOK TO STAY FAR ENOUGH NORTH THAT WE WILL STAY
OUT OF THE COLD AIR. DAYTIME HIGHS WILL RANGE FROM AROUND 50 NORTH
TO THE UPPER 50S DOWNEAST...AND OVERNIGHT LOWS IN THE 40S DUE TO
CLOUD COVER.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
RAIN SHOULD BE SPREADING NORTHWARD ON TUESDAY NIGHT IN RESPONSE TO
A LOW PRESSURE SYSTEM MOVING ALONG THE COAST OF MAINE. THERE ARE
STILL SOME DIFFERENCES IN THE GFS AND ECMWF IN THIS TIME FRAME.
THE GFS WANTS TO BRING THE LOW THROUGH ON TUESDAY NIGHT INTO
WEDNESDAY...ON THE OTHER HAND IT SEEMS AS IF THE ECMWF IS ABOUT 18
TO 24 HOURS SLOWER. WILL LEAN WITH GFS WITH THIS PACKAGE. RAIN
SHOULD END LATE WEDNESDAY EVENING. HIGH PRESSURE THEN MOVES IN FOR
THURSDAY THROUGH FRIDAY EVENING BEFORE A WEAK SYSTEM PASSES OFF TO
THE NORTH BRINGING A SLIGHT CHANCE OF PRECIP. TEMPERATURES AFTER
THE STORM WEDNESDAY WILL RETURN TO NORMAL NOVEMBER AVERAGES
THROUGH SATURDAY. USED A BLEND OF GMOS AND GFS FOR THE PERIOD AND
ADJUSTED AS NEEDED.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
NEAR TERM: VFR CONDITIONS TONIGHT AND SUNDAY. FLURRIES POSSIBLE
ACROSS NORTHERN TERMINALS INTO EARLY THIS EVENING BUT SHOULD NOT
RESTRICT VSBY.
SHORT TERM: VFR WITH PERIODS OF MVFR IN RAIN SHOWERS EXPECTED
THROUGH THE PERIOD.
&&
.MARINE...
NEAR TERM: SCA WINDS AND SEAS CONTINUE ACROSS THE WATERS THIS
EVENING AND THEN EXPECT WINDS TO DROP BELOW SCA CRITERIA AFTER
MIDNIGHT. HOWEVER, SEAS ABOVE 5 FEET DUE TO SWELL WILL CONTINUE
THROUGH THE NIGHT SO WILL KEEP SCA GOING FOR THE ENTIRE NIGHT.
SHORT TERM: SOUTHWEST WINDS OF 15 TO 25 KT ARE EXPECTED SUNDAY
NIGHT AND MONDAY AS LOW PRESSURE SKIRTS BY TO THE NORTH OF THE
WATERS. A SMALL CRAFT ADVISORY WILL PROBABLY BE NEEDED...FOR WAVES
AS WELL AS WINDS. CONDITIONS WILL SUBSIDE MONDAY NIGHT BUT WILL
INCREASE TO CLOSE TO SCA CRITERIA AGAIN TUESDAY AHEAD OF ANOTHER
LOW PRESSURE SYSTEM.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ050>052.
&&
$$
NEAR TERM...FOSTER
SHORT TERM...HASTINGS
LONG TERM...HILL
AVIATION...FOSTER
MARINE...FOSTER/HASTINGS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1212 PM EST SAT NOV 12 2011
.SYNOPSIS...
A HIGH PRESSURE RIDGE WILL BUILD ACROSS THE REGION TODAY AND
TONIGHT AND THEN MOVE EAST OF THE AREA ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE: SHORTWAVE TROUGH MOVING THROUGH QUEBEC WITH SNOW SHOWERS
LATE THIS MORNING. MODELS CONTINUE TO INDICATE THIS TROUGH TO WEAKEN AS
IT MOVES ACROSS NORTHERN MAINE BY EARLY THIS EVENING. SOME
WEAKENING EVIDENT AS IR SAT IMG INDICATING CLOUD TOPS STARTING TO
WARM. HOWEVER, HRRR MODEL INDICATES SOME LIGHT PRECIP ACROSS
NORTHERN MAINE AS THE TROUGH MOVES THROUGH SO HAVE ADDED FLURRIES
ACROSS NORTHERN SECTIONS FOR LATE THIS AFTERNOON.
INTENSE LOW PRESSURE MOVING NORTHWARD THROUGH LABRADOR TODAY AND
IS WORKING IN CONJUNCTION WITH STRONG HIGH PRESSURE OVER THE
SOUTHEASTERN STATES TO PRODUCE A STRONG PRESSURE GRADIENT ACROSS
NEW ENGLAND. A WEAK SHORT WAVE WILL MOVE ACROSS THE STATE TONIGHT
BUT EXCEPT FOR SNOW SHOWERS OVER HIGHER TERRAIN IN NORTHWEST IT
SHOULD STAY DRY. HAVE USED A BLEND OF NAM12...GFS40...ECMWF AND
SREF TO INITIALIZE THE POPS. SNOW SHOWERS THAT BROKE OUT LAST
EVENING ARE DIMINISHING IN INTENSITY AND EXPECTED TO SOON END. USE
A BLEND OF GMOS AND NAM12 FOR WIND AND GMOS FOR TEMPERATURE AND
DEW POINT. WILL MAKE SOME MINOR MANUAL ADJUSTMENTS TO THE MAXIMUM
AND MINIMUM TEMPERATURES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
ANOTHER ROUND OF MILD WEATHER IS SET FOR THE REGION THIS TERM.
A FRONTAL SYSTEM IS SHOWN BY ALL THE GUIDANCE TO MOVE INTO THE
REGION SUNDAY NIGHT INTO MONDAY. A MILD SSW FLOW AHEAD OF THE
FRONTAL SYSTEM IS EXPECTED TO MOVE INTO THE REGION ALONG WITH A
ROUND OF SHOWERS.
THE ASSOCIATED WARM FRONT IS SHOWN BY THE NAM/GFS AND ECMWF TO
LIFT ACROSS THE REGION ON SUNDAY BRINGING MILDER AIR NORTHWARD.
MODEL SOUNDINGS SHOW MID AND HIGH LEVEL MOISTURE AFFECTING THE
NORTHERN AND WESTERN AREAS ON SUNDAY LEADING TO PARTLY TO MOSTLY
CLOUDY CONDITIONS BY AFTERNOON. DOWNEAST AND THE COAST WILL SEE
GENERALLY MOSTLY SUNNY TO PARTLY CLOUDY SKIES. TEMPERATURES ARE
EXPECTED TO CLIMB INTO THE UPPER 40S TO AROUND 50 NORTH AND LOW TO
MID 50S CENTRAL AND DOWNEAST AREAS. KEPT SUNDAY DRY W/DRY AIR IN LLVLS.
DEEPER MOISTURE IS SHOWN BY THE NAM/GFS AND EVEN THE SREF TO SPREAD
ACROSS THE REGION SUNDAY NIGHT INTO MONDAY AS THE COLD FRONT
APPROACHES FROM THE WEST. THEREFORE...DECIDED TO INCREASE THE POPS
AS WELL W/HIGHEST PERCENTAGES ACROSS THE NORTH AND WEST WHERE THE
BEST FORCING IS SITUATED. TEMPERATURES ON MONDAY WILL BE ABOVE
NOVEMBER NORMALS. BOOSTED WIND GUSTS UP BY 10 MPH ON MONDAY W/THE
FROPA.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A CONTINUATION OF MILD WEATHER INTO MID WEEK AND THEN A RETURN TO
MORE NORMAL TEMPERATURES BY LATE WEEK.
WEAK RIDGING LATE MONDAY AFTERNOON INTO MONDAY NIGHT WILL LEAD TO
SOME DRYING BEFORE THE NEXT SYSTEM AFFECTS THE REGION ON TUESDAY
INTO WEDNESDAY. STARTED THINGS OUT W/THE GMOS AND THEN ADJUSTED
W/THE ECMWF AND GFS ENSEMBLE. TUESDAY LOOKS BE A VERY MILD DAY AS
A SSW FLOW AHEAD THE STORM SYSTEM BRINGS 925-850MBS TEMPS OF
10-13C RESPECTIVELY. THE ECMWF AND GFS BOTH INDICATE A DECENT LLVL
JET OF 50KTS TUESDAY AFTERNOON INTO TUESDAY EVENING. THIS WILL
LEAD TO A WINDY TUESDAY AFTERNOON AND EVENING W/SCATTERED SHOWERS
ACROSS THE NORTH AND WEST. GMOS MAXES FOR TUESDAY WERE ADJUSTED A
FEW UPWARD TO HAVE THE CWA IN THE 50S.
THE GFS AND ECMWF DIVERGE TUESDAY NIGHT INTO WEDNESDAY. THE GFS
POINTS TO A FRONTAL BOUNDARY SWEEPING ACROSS THE REGION ON
WEDNESDAY W/THE MAIN LOW MOVING ACROSS QUEBEC. THE ECMWF SHOWS
LOW PRES DEVELOPING ON THE FRONT TUESDAY NIGHT AND MOVES IT NE
ACROSS THE REGION ON WEDNESDAY. THE GFS SOLUTION WOULD MEAN
SHOWERS TUESDAY NIGHT INTO WEDNESDAY WHILE THE ECMWF SOLUTION
WOULD SPELL OUT A SOAKING RAIN. THE CANADIAN HEMISPHERIC AND THE
GFS ENSEMBLE KEEP THE MAIN LOW THROUGH QUEBEC W/A FRONTAL SYSTEM
SWEEPING THROUGH THE CWA ON WEDNESDAY MATCHING CLOSE TO THE GFS.
THEREFORE...DECIDED TO BACK AWAY FROM THE ECMWF ATTM AND GO W/CHC
POPS FOR ALL AND PUSH PRECIP SHIELD TO THE EAST BY WEDNESDAY NIGHT
W/COLDER AIR MOVING IN BEHIND THE SYSTEM. THIS COLDER AIR WILL
BRING CONDITIONS BACK TO NEAR NORMAL FOR LATE WEEK. TWEAKED GMOS
MAXES A FEW DEGREES ON WEDNESDAY TO KEEP THEM UP A FEW DEGREES
FROM GMOS. GMOS MAXES WERE ACCEPTED THURSDAY INTO FRIDAY. GMOS
MINS WERE ADJUSTED UPWARD BY A CATEGORY TUESDAY NIGHT AND
WEDNESDAY NIGHT GIVEN THAT CLOUDS AND PRECIP ARE EXPECTED.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR CONDITIONS EXPECTED NEXT 24 HOURS.
SHORT TERM: VFR THROUGH MONDAY AND THEN CONDITIONS COULD DROP TO
MVFR MONDAY NIGHT AND POSSIBLY IFR/MVFR FOR TUESDAY W/ FRONTAL
SYSTEM EXPECTED TO MOVE THROUGH THE REGION.
&&
.MARINE...
NEAR TERM: A BLEND OF THE NAM12 AND GFS40 WAS USED FOR THE WIND
GRIDS WITH WIND GUSTS 25 PERCENT ABOVE SUSTAINED WINDS. FOR WAVES:
LONG PERIOD WAVE GENERATED IN FETCH SOUTH AND EAST OF GULF OF
MAINE CURRENTLY ARRIVING IN LOCAL WATERS AND HAS COMBINED WITH
OFF-SHORE WIND WAVE GROUP. WAVE MODEL GUIDANCE APPEARS TO BE
BRINGING THE LONG PERIOD WAVE DOWN TOO FAST BUT EXPECT IT TO
SUBSIDE SLOWLY DURING THE DAY TODAY. WINDS WILL REMAIN STRONG
TODAY AND WOULD EXPECT WIND WAVE GROUP TO BECOME DOMINATE GROUP BY
MID AFTERNOON. PLAN TO LOWER GALE TO SCA.
SHORT TERM: SCA CONDITIONS ARE POSSIBLE BY SUNDAY NIGHT INTO
MONDAY AS SW WINDS INCREASE AHEAD OF THE APPROACHING FRONT.
THINKING ATTM IS THAT SCA WILL BE FOR WIND GUSTS TO 25 KTS AND
SEAS BUILDING TO 6 FT BY MONDAY. AS A MATTER OF FACT...SCA
CONDITIONS COULD VERY WELL HOLD ON RIGHT INTO WEDNESDAY AS YET
ANOTHER SYSTEM IS SHOWN TO AFFECT THE WATERS. DECIDED TO BACK AWAY
FROM HIGHER GUSTS THAT THE GMOS WAS SHOWING(35KTS) ESPECIALLY
LATER MONDAY THROUGH TUESDAY. A WARM SW FLOW OVER COOLER WATERS
TENDS TO REMAIN ALOFT THIS TIME OF YEAR. WAVE HEIGHTS WERE
INITIALIZED W/THE WNAWAVE AND THEN KNOCKED DOWN BY 1-2 FT GIVEN
SYNOPTIC SETUP.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST SUNDAY FOR ANZ050>052.
&&
$$
NEAR TERM...FOSTER/MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...FOSTER/MIGNONE
MARINE...FOSTER/MIGNONE/HEWITT
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
249 PM EST SAT NOV 12 2011
.SYNOPSIS...
HIGH PRESSURE ACROSS THE MID-ATLANTIC WILL ALLOW FOR A DRY
WEEKEND WITH BREEZY CONDITIONS. A SLOW MOVING COLD FRONT WILL
RETURN THE CHANCE OF RAIN LATE ON SUNDAY THROUGH TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES THE UPPER OHIO VALLEY
IN A ZONAL 500MB FLOW, WITH A DEEP LAYER OF DRY AIR ALOFT.
UPSTREAM, A WEAK RIDGE AXIS EXTENDS FROM THE UPPER MIDWEST INTO
THE NORTHERN GULF STATES. AT THE SURFACE, A 1028MB HIGH IS LOCATED
ACROSS THE SOUTHEAST. THIS HIGH IS DOMINATING THE WEATHER PATTERN
FOR THE EASTERN HALF OF THE US. THE PRESSURE GRADIENT
BETWEEN THE HIGH AND A LOW WELL UPSTREAM ACROSS THE NORTHERN
PLAINS HAS ALLOWED FOR WINDS TO BEGIN TO GUST TO AROUND 25 MPH THIS
AFTERNOON.
TONIGHT...A LOW-LEVEL SOUTHERLY FLOW WILL BE IN PLACE WELL AHEAD OF
A COLD FRONT MOVING INTO THE PLAINS. CIRRUS CLOUDS WILL FILTER INTO
THE AREA WELL AHEAD OF THIS SYSTEM. OVERNIGHT LOWS ARE FORECAST A
FEW DEGREES ABOVE A MAV/MET BLEND, AROUND 5 DEGREES ABOVE NORMAL.
SUNDAY...THE SURFACE HIGH WILL PUSH OFF THE CAROLINA COAST WITH THE
AREA REMAINING IN A SOUTHERLY FLOW BETWEEN THE HIGH AND A SURFACE
TROUGH ACROSS THE UPPER MIDWEST. A TIGHTENED PRESSURE GRADIENT
WILL AGAIN ALLOW FOR WINDS TO DIURNALLY MIX DOWN TO THE SURFACE
AND BECOME GUSTY AGAIN BY LATE MORNING. GFS/NAM SUPPORT GUSTS OF
25 TO 30 MPH ACROSS THE LOWLANDS AND GUSTS UP TO 35 MPH ACROSS
THE RIDGES. A COLD FRONT WILL APPROACH THE WEST LATE IN THE DAY,
ENHANCING WARM AIR ADVECTION. THUS, HIGHS WILL BE AROUND 10
DEGREES ABOVE NORMAL.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
A FRONTAL BOUNDARY WILL PUSH NORTHEAST OF THE AREA ON SUNDAY NIGHT.
FORECAST IS CLOSEST TO A GFS/ECMWF BLEND WITH THE CHANCE OF SHOWERS
OVERNIGHT BECOMING MORE LIKELY BY DAWN ON MONDAY. WITH CLOUD
COVERAGE AND WARM AIR ADVECTION AHEAD OF THE FRONT, TEMPS WILL BE 15
DEGREES ABOVE NORMAL FOR LOWS SUNDAY NIGHT, RANGING FROM THE UPPER
40S ACROSS THE EASTERN RIDGES TO THE LOWER 50S ACROSS THE LOWLANDS.
MONDAY THROUGH TUESDAY...A COLD FRONT WILL SLOWLY TRACK ACROSS THE OHIO
VALLEY, WITH SEVERAL ROUNDS OF SHOWERS PUSHING ACROSS THE AREA IN A
SOUTHWESTERLY FLOW. LIKELY POPS ARE FORECAST THROUGH THE MAJORITY
OF THIS PERIOD AS A FEW WAVES RIDE FROM THE NORTHERN GULF STATES
ALONG THE FRONTAL BOUNDARY AND ACROSS THE AREA. THE COLD FRONT
WILL FINALLY BEGIN TO WORK ACROSS THE AREA LATE ON TUESDAY. TEMPS
ON MONDAY AND MONDAY NIGHT WILL BE 10 TO 15 DEGREES ABOVE NORMAL.
ONGOING RAINFALL AND CLOUD COVERAGE WILL LIMIT TEMPS SOMEWHAT ON
TUESDAY, WITH HIGHS AROUND 5 DEGREES ABOVE NORMAL. RAINFALL WILL
BE LIGHT IN NATURE FOR THE MAJORITY WITH A TOTAL OF AN INCH TO AN
INCH AND A HALF OF RAINFALL THROUGH LATE TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
PER BLEND OF RECENT NAEFS AND ECMWF MODEL OUTPUT, EXPECT SHOWER
BANDS ASSOCIATED WITH COLD FRONTAL SYSTEM TO BE EXITING PAST THE
MOUNTAINS TUESDAY NIGHT.
COLD POST-SYSTEM WESTERLY FLOW WILL PROVIDE COLDER THAN NORMAL
TEMPERATURES WEDNESDAY AND THURSDAY, AND MAY MAINTAIN CLOUDS AND A
SLIGHT CHANCE OF SHOWERS ACROSS THE I-80 CORRIDOR AND MOUNTAINS.
AS TENNESSEE VALLEY HIGH PRESSURE EXITS EAST, LOW LEVEL WINDS WILL
TURN SOUTHWEST TO PROVIDE A DRY WARM UP FRIDAY AND SATURDAY, PER
BLEND OF RECENT GFS MOS AND NAEFS MEDIAN VALUES.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
VFR WILL CONTINUE THROUGH SUNDAY, WITH NO MORE THAN BANDS OF HIGH
CLOUDS EXPECTED.
HAVE MADE USE OF NAM MODEL PROFILES TO FORECAST DIURNAL WIND
VARIATION. EXPECT SOUTHWEST WINDS TO GUST TO 25-28 KTS INTO EARLY
EVENING. HAVE FORECASTED ONSET OF LOW LEVEL WIND SHEAR TONIGHT AS A
SURFACE INVERSION DECOUPLES THE 40-50 KT WINDS AT 2 KFT AGL FROM
SURFACE WINDS OF NO MORE THAN 10 KTS. DAYTIME HEATING WILL LEAD TO
DEEP VERTICAL MIXING AGAIN SUNDAY WITH SURFACE WINDS GUSTING TO 30
KTS.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
SHOWERS ASSOCIATED WITH A SLOW MOVING COLD FRONTAL SYSTEM WILL
PROVIDE PERIODS OF RESTRICTIONS SUNDAY NIGHT INTO TUESDAY NIGHT
AREA WIDE, AND POSSIBLY WEDNESDAY ACROSS THE NORTH AND MOUNTAINS.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
110 PM EST SAT NOV 12 2011
.SYNOPSIS...
HIGH PRESSURE ACROSS THE MID-ATLANTIC WILL ALLOW FOR A DRY
WEEKEND WITH BREEZY CONDITIONS. A SLOW MOVING COLD FRONT WILL
RETURN THE CHANCE OF RAIN LATE ON SUNDAY THROUGH TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE 18Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED WITH
THE ONLY CHANGE BEING TO INCREASE GUSTY WINDS FOR SUNDAY.
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES THE UPPER OHIO VALLEY
IN A ZONAL 500MB FLOW, WITH A DEEP LAYER OF DRY AIR ALOFT.
UPSTREAM, A WEAK RIDGE AXIS EXTENDS FROM THE UPPER MIDWEST INTO
THE NORTHERN GULF STATES. AT THE SURFACE, A 1028MB HIGH IS LOCATED
ACROSS THE SOUTHEAST. THIS HIGH IS DOMINATING THE WEATHER PATTERN
FOR THE EASTERN HALF OF THE US. THE PRESSURE GRADIENT
BETWEEN THE HIGH AND A LOW WELL UPSTREAM ACROSS THE NORTHERN
PLAINS HAS ALLOWED FOR WINDS TO BEGIN TO GUST TO AROUND 25 MPH THIS
AFTERNOON.
THIS AFTERNOON...THE SURFACE HIGH WILL SLOWLY SLIDE OFF THE
SOUTHEAST COAST AS THE WEAK MID-LEVEL RIDGE MOVES INTO THE UPPER
OHIO VALLEY. THE DEEP LAYER OF DRY AIR ALOFT WILL ALLOW FOR
CONTINUED CLEAR SKIES TODAY. WARM ADVECTION IN A SOUTHWESTERLY
FLOW WILL ALLOW FOR TEMPERATURES TO WARM NICELY TODAY. HIGHS TODAY
WILL BE AROUND 5 DEGREES ABOVE NORMAL, RANGING FROM THE MID 50S
ACROSS THE EASTERN RIDGES TO THE LOWER 60S ACROSS EASTERN OHIO AND
NORTH-CENTRAL WV. THE TIGHTENED PRESSURE GRADIENT BETWEEN THE
HIGH AND THE LOW ACROSS THE PLAINS WILL CREATE BREEZY CONDITIONS
TODAY...WITH GUSTS AROUND 25 MPH ACROSS THE LOWLANDS AND INTO THE
30S ACROSS THE HIGHER ELEVATIONS.
TONIGHT...A LOW-LEVEL SOUTHERLY FLOW WILL CONTINUE WELL AHEAD OF A
COLD FRONT MOVING INTO THE PLAINS. CIRRUS WILL FILTER INTO THE
AREA WELL AHEAD OF THIS SYSTEM. OVERNIGHT LOWS ARE FORECAST A FEW
DEGREES ABOVE A MAV/MET BLEND, AROUND 5 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
SIMILAR SITUATION ANTICIPATED FOR SUNDAY WITH WINDY CONDITIONS AND
HIGH TEMPERATURES PROGGED ABOUT 10 DEGREES ABOVE THE AVERAGES IN THE
WARM SOUTHERLY FLOW. HOWEVER...PRECIPITATION PROBABILITIES WILL
ALSO BE ON THE RISE LATE IN THE DAY AS A COLD FRONT IS PULLED
TOWARD THE NORTHWESTERN TIER OF PBZ COUNTIES.
WITH DEEPENING TROUGH FORECAST IN THE MID/UPPER LEVELS OVER THE
CENTRAL U.S...SURFACE FRONT IS EXPECTED TO STALL OVER/NEAR THE
REGION BY MONDAY AND SERVE TO FOCUS SHOWERS FOR THE CLOSE OF THE
SHORT TERM PERIOD. RAIN CHANCES WERE INCREASED TO LIKELY NUMBERS
FOR SUNDAY NIGHT AND MONDAY AND TEMPERATURES WERE FORECAST USING
THE LATEST GFS DEPICTION OF FRONTAL PROGRESS...CONFIDENCE IN WHICH
IS MINIMAL AT MOMENT.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
SPREAD BETWEEN MODELS IS BEGINNING TO DECREASE...WITH THE
ECMWF/GFS SHOWING A COLD FRONT HANGING ACROSS THE UPPER OHIO
VALLEY MONDAY NIGHT/TUESDAY...EXITING THE REGION TUESDAY
NIGHT INTO WEDNESDAY. WITH TIMING DIFFERENCES REMAINING...WILL
USE HIGH END CHANCE POPS INTO TUESDAY...WITH DIMINISHING
CHANCES TUESDAY NIGHT. ZONAL FLOW TO LOW AMPLITUDE RIDGING IS
PROGGED FOR WEDNESDAY THROUGH FRIDAY FOR MAINLY DRY CONDITIONS.
ABOVE NORMAL TEMPERATURES MONDAY NIGHT/TUESDAY WILL COOL TO
BELOW NORMAL FOR THE LAST HALF OF THE WEEK.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR WILL CONTINUE THROUGH THE WEEKEND, WITH NO MORE THAN BANDS OF
CIRRUS TONIGHT AND PERHAPS ALTOCUMULUS SUNDAY.
HAVE MADE USE OF NAM MODEL PROFILES TO FORECAST DIURNAL WIND
VARIATION. EXPECT SOUTHWEST WINDS TO GUST TO 25-28 KTS INTO EARLY
EVENING. HAVE FORECASTED ONSET OF LOW LEVEL WIND SHEAR TONIGHT AS A
SURFACE INVERSION DECOUPLES THE 40-50 KT WINDS AT 2 KFT AGL FROM
SURFACE WINDS OF NO MORE THAN 10 KTS. DAYTIME HEATING WILL LEAD TO
DEEP VERTICAL MIXING AGAIN SUNDAY WITH SURFACE WINDS GUSTING TO 30
KTS.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...
THE NEXT MIDWEST FRONTAL SYSTEM WILL AFFECT THE AREA SUNDAY NIGHT
INTO WEDNESDAY WITH PERIODS OF SHOWERS AND RESTRICTIONS.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1047 AM EST SAT NOV 12 2011
.SYNOPSIS...
HIGH PRESSURE ACROSS THE MID-ATLANTIC WILL ALLOW FOR A DRY
WEEKEND WITH BREEZY CONDITIONS TODAY. A SLOW MOVING COLD FRONT
WILL RETURN THE CHANCE OF RAIN LATE ON SUNDAY THROUGH TUESDAY
NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
A MORNING UPDATE HAS BEEN ISSUED WITH LITTLE CHANGE TO THE GOING
FORECAST. SLIGHTLY WARMER TRENDS IN OBS AND LAMP MODEL GUIDANCE
HAVE LED TO HIGH TEMPS ADJUSTED UP A DEGREE.
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES THE UPPER OHIO VALLEY
IN A ZONAL 500MB FLOW, WITH A DEEP LAYER OF DRY AIR ALOFT.
UPSTREAM, A WEAK RIDGE AXIS EXTENDS FROM THE UPPER MIDWEST INTO
THE NORTHERN GULF STATES. AT THE SURFACE, A 1028MB HIGH IS LOCATED
ACROSS THE SOUTHEAST. THIS HIGH IS DOMINATING THE WEATHER PATTERN
FOR THE EASTERN HALF OF THE US. THE PRESSURE GRADIENT
BETWEEN THE HIGH AND A LOW WELL UPSTREAM ACROSS THE NORTHERN
PLAINS HAS ALLOWED FOR WINDS TO BEGIN TO GUST AT 20 TO 25 MPH THIS
MORNING. RUC 925MB WINDS INDICATE 35KTS WITH SOME DIURNAL
ADIABATIC MIXING DOWN TO THE SURFACE BEGINNING TO OCCUR.
TODAY...THE SURFACE HIGH WILL SLOWLY SLIDE OFF THE SOUTHEAST COAST
AS THE WEAK MID-LEVEL RIDGE MOVES INTO THE UPPER OHIO VALLEY. A
DEEP LAYER OF DRY AIR ALOFT WILL ALLOW FOR CONTINUED CLEAR SKIES
TODAY. WARM ADVECTION IN A SOUTHWESTERLY FLOW WILL ALLOW FOR
TEMPERATURES TO WARM NICELY TODAY. HIGHS TODAY WILL BE AROUND 5
DEGREES ABOVE NORMAL, RANGING FROM THE MID 50S ACROSS THE
EASTERN RIDGES TO THE LOWER 60S ACROSS EASTERN OHIO AND NORTH-
CENTRAL WV. THE TIGHTENED PRESSURE GRADIENT BETWEEN THE HIGH AND
THE LOW ACROSS THE PLAINS WILL CREATE BREEZY CONDITIONS
TODAY...WITH GUSTS AROUND 25 MPH ACROSS THE LOWLANDS AND INTO THE
30S ACROSS THE HIGHER ELEVATIONS.
TONIGHT...A LOW-LEVEL SOUTHERLY FLOW WILL CONTINUE WELL AHEAD OF A
COLD FRONT MOVING INTO THE PLAINS. CIRRUS WILL FILTER INTO THE
AREA WELL AHEAD OF THIS SYSTEM. OVERNIGHT LOWS ARE FORECAST A FEW
DEGREES ABOVE A MAV/MET BLEND, AROUND 5 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
SIMILAR SITUATION ANTICIPATED FOR SUNDAY WITH WINDY CONDITIONS AND
HIGH TEMPERATURES PROGGED ABOUT 10 DEGREES ABOVE THE AVERAGES IN THE
WARM SOUTHERLY FLOW. HOWEVER...PRECIPITATION PROBABILITIES WILL
ALSO BE ON THE RISE LATE IN THE DAY AS A COLD FRONT IS PULLED
TOWARD THE NORTHWESTERN TIER OF PBZ COUNTIES.
WITH DEEPENING TROUGH FORECAST IN THE MID/UPPER LEVELS OVER THE
CENTRAL U.S...SURFACE FRONT IS EXPECTED TO STALL OVER/NEAR THE
REGION BY MONDAY AND SERVE TO FOCUS SHOWERS FOR THE CLOSE OF THE
SHORT TERM PERIOD. RAIN CHANCES WERE INCREASED TO LIKELY NUMBERS
FOR SUNDAY NIGHT AND MONDAY AND TEMPERATURES WERE FORECAST USING
THE LATEST GFS DEPICTION OF FRONTAL PROGRESS...CONFIDENCE IN WHICH
IS MINIMAL AT MOMENT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
SPREAD BETWEEN MODELS IS BEGINNING TO DECREASE...WITH THE
ECMWF/GFS SHOWING A COLD FRONT HANGING ACROSS THE UPPER OHIO
VALLEY MONDAY NIGHT/TUESDAY...EXITING THE REGION TUESDAY
NIGHT INTO WEDNESDAY. WITH TIMING DIFFERENCES REMAINING...WILL
USE HIGH END CHANCE POPS INTO TUESDAY...WITH DIMINISHING
CHANCES TUESDAY NIGHT. ZONAL FLOW TO LOW AMPLITUDE RIDGING IS
PROGGED FOR WEDNESDAY THROUGH FRIDAY FOR MAINLY DRY CONDITIONS.
ABOVE NORMAL TEMPERATURES MONDAY NIGHT/TUESDAY WILL COOL TO
BELOW NORMAL FOR THE LAST HALF OF THE WEEK.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
VFR WILL CONTINUE THROUGH THE WEEKEND, WITH NO MORE THAN BROKEN
ALTOCUMULUS OR CIRRUS TONIGHT AND SUNDAY.
AS DAYTIME HEATING HAS INCREASED VERTICAL MIXING AND WILL HAVE
DISSIPATED SURFACE INVERSION BY 15Z-16Z, NO LONGER EXPECT LOW LEVEL
WIND SHEAR, BUT EXPECT SURFACE WINDS FROM THE SOUTHWEST TO GUST UP
TO 25 KTS THROUGH EARLY EVENING.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...
THE NEXT FRONTAL SYSTEM WILL AFFECT THE AREA SUNDAY NIGHT THROUGH
TUESDAY WITH PERIODS OF SHOWERS AND RESTRICTIONS. THE SYSTEM IS
PROJECTED TO EXIT THE AREA BY MIDWEEK, WITH VFR CONDITIONS RETURNING
FOR WEDNESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
127 PM EST SAT NOV 12 2011
UPDATED AVIATION DISCUSSION FOR 18Z TAFS
.SYNOPSIS...
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW FLOW OVER THE GREAT LAKES
BACKING MORE WESTERLY AS TROF EXTENDING FROM HUDSON BAY TO NEW
ENGLAND CONTINUES TO SHIFT E. UPSTREAM...A POTENT SHORTWAVE WAS
DROPPING THRU THE PACIFIC NW STATES. 00Z RAOBS REVEALED VERY
IMPRESSIVE 12HR HEIGHT FALLS OF 230M AT 500MB ASSOCIATED WITH THE
WAVE OVER WRN WA. DOWNSTREAM...A RIDGE IS SHIFTING OUT OVER THE WRN
PLAINS. AT THE SFC...LOW-LEVEL W TO SW FLOW HAS DEVELOPED OVER THE
UPPER GREAT LAKES BTWN BROAD LOW PRES FROM THE ROCKIES TO NRN
ONTARIO AND HIGH PRES OVER THE SE STATES. ONGOING MODEST WAA IS ONLY
PRODUCING SOME SCT MID AND HIGH CLOUDS ACROSS THE FCST AREA EARLY
THIS MORNING.
&&
.DISCUSSION...
THE NEXT FEW DAYS WILL FEATURE A RETURN TO ABOVE NORMAL TEMPS AS
MID/UPPER LEVEL FLOW BECOMES SOUTHWESTERLY INTO THE UPPER GREAT
LAKES. COLDER WEATHER/BLO NORMAL TEMPS WILL THEN RETURN DURING THE
MIDDLE OF THE UPCOMING WEEK. THE NEXT POTENTIAL FOR PCPN WILL BE
TIED TO POTENT SHORTWAVE NOW OVER THE PACIFIC NW.
QUIET/WARMER WEATHER EXPECTED TODAY AS WAA CONTINUES ALONG WITH A
DECENT DISPLAY OF SUNSHINE. LINGERING...MELTING SNOW COVER WILL
TEMPER WARMING SOME OVER PARTS OF THE CNTRL AND W. HIGHS MAY REACH
THE MID 40S THERE. A FEW LOCATIONS OVER THE FAR W MAY TOP OUT AROUND
50F.
LOW-LEVEL MOISTURE ADDED BY MELTING SNOW TODAY COULD LEAD TO STRATUS
AND SOME FOG LATER TONIGHT/SUN MORNING AS SUGGESTED BY SOME OF THE
NAM/GFS MOS GUIDANCE AND BY NAM MODEL OUTPUT/SREF PROBABILITIES.
OTHERWISE...EXPECT A MILD NIGHT AS SW FLOW STRENGTHENS (850MB WINDS
INCREASE TO 40-50KT) AS DEEP LOW PRES MOVES TOWARD NRN ONTARIO.
EXPECT MINS IN THE MID 30S TO LWR 40S WITH THE WARMEST READINGS IN
THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR AND DOWNWIND OF LAKE MI IN
SRLY FLOW.
ON SUN...LOW PRES WILL MOVE ACROSS NRN ONTARIO WITH ASSOCIATED COLD
FRONT MOVING ACROSS UPPER MI. STRONG SHORTWAVE NOW OVER THE PACIFIC
NW WILL ALSO SWING OUT INTO THE PLAINS TONIGHT AND THEN ROTATE INTO
THE UPPER LAKES SUN. ALTHOUGH SHORTWAVE WILL BE WEAKENING...THE
WELL-DEFINED APPEARANCE/STRONG HEIGHT FALLS PER 00Z RAOBS SUGGEST
CONTINUING TO FAVOR THE WETTER SOLUTIONS FOR SUN. MODEL CONSENSUS
DEPICTS FAIRLY STRONG DEEP LAYER QVECTOR CONVERGENCE QUICKLY LIFTING
ACROSS THE CENTRAL AND ERN FCST AREA AS VORT CENTER TRACKS ACROSS
SRN WI AND THRU NRN LWR MI. ALONG THE TRACK OF THE VORT CENTER...
STEEP MIDLEVEL LAPSE RATES IN EXCESS OF 7C/KM AND SHOWALTER INDEX
AROUND OR JUST BLO 0C ARE NOTED WHICH SUGGESTS SOME CONVECTION COULD
BE ASSOCIATED WITH SYSTEM. WILL BE SOMETHING TO KEEP IN MIND IN
LATER FCSTS IF SHORTWAVE TRACKS A LITTLE FARTHER N AS SUGGESTED BY
THE HIGH RES-ARW. IN ANY EVENT...POPS WILL SHOW A GRADIENT FROM
SLIGHT CHC NW TO LIKELY SE SUN. CLOUD COVER AND PROBABLE PCPN WILL
LIMIT TEMP RISE DESPITE MILD START TO THE DAY. EXPECT MAX TEMPS OF
MID 40S TO AROUND 50.
BRIEF SHOT OF PCPN (3-6HRS) WILL BE OUT OF THE AREA BY SUN EVENING.
BEHIND COLD FRONT...CAA AND ASSOCIATED INCREASED MIXING COULD LEAD
TO WIND GUSTS TO AROUND 40 MPH OVER THE KEWEENAW PENINSULA SUN
EVENING IN FAVORABLE WRLY FLOW (NAM/GFS BOTH SHOW 40KT WINDS WITHIN
1KFT). 850MB TEMPS BRIEFLY FALLING TO -4C WON`T BE SUFFICIENT FOR
ANY LAKE EFFECT PCPN SUN NIGHT.
MEDIUM RANGE GUIDANCE OVER THE LAST FEW DAYS HAS OCCASIONALLY
SUGGESTED POTENTIAL FOR PCPN MON WITH SHORTWAVE ENERGY LIFTING NE
FROM LONGWAVE TROF AXIS ACROSS THE WRN PLAINS. WHILE CLOSE...BULK OF
GUIDANCE SUGGESTS PCPN WILL STAY SE OF THE FCST AREA. SO AT THIS
POINT...PLAN TO MAINTAIN A DRY FCST.
NEXT SHORTWAVE OF INTEREST WILL DROP INTO THE NRN PLAINS MON NIGHT
AND THEN TRACK THRU THE WRN GREAT LAKES LATE TUE. SYSTEM LOOKS
FAIRLY STRONG WITH 500MB HEIGHT FALLS OF AT LEAST 100M...SO LOW CHC
POPS LOOK ON TRACK WITH COLD FROPA TUE. GOOD PUSH OF CAA (850MB
TEMPS FALL TO AROUND -9C TUE NIGHT) ALONG WITH TIGHT PRES GRADIENT
WILL LEAD TO GALES ACROSS LAKE SUPERIOR AS 850MB WINDS ARE FCST AT
35-45KT. FAVORABLE WNW WIND DIRECTION WILL ALSO SUPPORT GUSTS OF
40-45MPH ACROSS THE KEWEENAW AND LAKESHORE AREAS EXPOSED TO A WNW
WIND. LAKE EFFECT COULD KICK INTO HIGH GEAR TUE NIGHT/WED AS 850MB
TEMPS FALL TO AROUND -9C...BUT 00Z GFS SOUNDINGS SHOW A DRY BOUNDARY
LAYER/INVERTED-V LOOK WHICH WOULD BE A BIG NEGATIVE FOR SIGNIFICANT
LES IF THAT VERIFIES. ECMWF IS MORE BULLISH WITH PCPN DOWNWIND OF
THE LAKE. IN ANY EVENT...THIS WILL BE A PERIOD TO MONITOR FOR LAKE
EFFECT SNOW ACCUMULATIONS IN THE COMING DAYS.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
VFR CONDITIONS ARE EXPECTED THROUGH EARLY THIS EVENING AS A WEAK
HIGH PRESSURE RIDGE SLIDES THROUGH THE AREA. THE INCREASING SRLY
FLOW AND MELTING SNOW TODAY WILL COMBINE TO MOISTEN LOW LEVELS
TONIGHT. LOWER CLOUDS AND SOME FOG SHOULD DEVELOP BY LATE EVENING AT
KSAW. SOUTH WINDS WILL DELAY FORMATION OF LOW CLOUDS UNTIL NEAR
SUNRISE AT KIWD AND KCMX...BUT DECIDED TO INSERT AN MVFR CLOUD DECK
AROUND 11Z WITH CONDITIONS SLOWLY IMPROVING BY LATE MORNING. STRONG
LOW-LEVEL WINDS JUST ABOVE INVERSION NEAR THE SFC WILL RESULT IN
WIND SHEAR AT ALL SITES BEGINNING THIS EVENING.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
ACTIVE PERIOD ON THE LAKE THROUGH MUCH OF NEXT WEEK. LOW PRESSURE
PUSHING FROM THE DAKOTAS TODAY TO ONTARIO THROUGH SUNDAY WILL BRING
A PERIOD OF STRONG SOUTHERLY WINDS TO LK SUPERIOR LATE TODAY THROUGH
SUNDAY MORNING. STRONGEST WINDS...30 KTS WITH GALE GUSTS 35-40
KTS...WILL OCCUR OVER EASTERN HALF OF LK SUPERIOR. TROUGH TIED TO
THE LOW WILL SWING ACROSS LK SUPERIOR SUNDAY AFTERNOON ALLOWING FOR
WESTERLY WINDS TO 30 KTS WITH GALE GUSTS TO 35 KTS OVR MUCH OF THE
LAKE THROUGH SUNDAY NIGHT. YET ANOTHER OPPORTUNITY FOR WESTERLY GALE
FORCE WINDS OCCURS TUESDAY NIGHT THROUGH WEDNESDAY IN WAKE OF STRONG
COLD FRONT PASSING THROUGH TUESDAY AFTN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...ROLFSON
DISCUSSION...ROLFSON
AVIATION...VOSS
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
640 AM EST SAT NOV 12 2011
UPDATED AVIATION DISCUSSION FOR 12Z TAFS
.SYNOPSIS...
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW FLOW OVER THE GREAT LAKES
BACKING MORE WESTERLY AS TROF EXTENDING FROM HUDSON BAY TO NEW
ENGLAND CONTINUES TO SHIFT E. UPSTREAM...A POTENT SHORTWAVE WAS
DROPPING THRU THE PACIFIC NW STATES. 00Z RAOBS REVEALED VERY
IMPRESSIVE 12HR HEIGHT FALLS OF 230M AT 500MB ASSOCIATED WITH THE
WAVE OVER WRN WA. DOWNSTREAM...A RIDGE IS SHIFTING OUT OVER THE WRN
PLAINS. AT THE SFC...LOW-LEVEL W TO SW FLOW HAS DEVELOPED OVER THE
UPPER GREAT LAKES BTWN BROAD LOW PRES FROM THE ROCKIES TO NRN
ONTARIO AND HIGH PRES OVER THE SE STATES. ONGOING MODEST WAA IS ONLY
PRODUCING SOME SCT MID AND HIGH CLOUDS ACROSS THE FCST AREA EARLY
THIS MORNING.
&&
.DISCUSSION...
THE NEXT FEW DAYS WILL FEATURE A RETURN TO ABOVE NORMAL TEMPS AS
MID/UPPER LEVEL FLOW BECOMES SOUTHWESTERLY INTO THE UPPER GREAT
LAKES. COLDER WEATHER/BLO NORMAL TEMPS WILL THEN RETURN DURING THE
MIDDLE OF THE UPCOMING WEEK. THE NEXT POTENTIAL FOR PCPN WILL BE
TIED TO POTENT SHORTWAVE NOW OVER THE PACIFIC NW.
QUIET/WARMER WEATHER EXPECTED TODAY AS WAA CONTINUES ALONG WITH A
DECENT DISPLAY OF SUNSHINE. LINGERING...MELTING SNOW COVER WILL
TEMPER WARMING SOME OVER PARTS OF THE CNTRL AND W. HIGHS MAY REACH
THE MID 40S THERE. A FEW LOCATIONS OVER THE FAR W MAY TOP OUT AROUND
50F.
LOW-LEVEL MOISTURE ADDED BY MELTING SNOW TODAY COULD LEAD TO STRATUS
AND SOME FOG LATER TONIGHT/SUN MORNING AS SUGGESTED BY SOME OF THE
NAM/GFS MOS GUIDANCE AND BY NAM MODEL OUTPUT/SREF PROBABILITIES.
OTHERWISE...EXPECT A MILD NIGHT AS SW FLOW STRENGTHENS (850MB WINDS
INCREASE TO 40-50KT) AS DEEP LOW PRES MOVES TOWARD NRN ONTARIO.
EXPECT MINS IN THE MID 30S TO LWR 40S WITH THE WARMEST READINGS IN
THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR AND DOWNWIND OF LAKE MI IN
SRLY FLOW.
ON SUN...LOW PRES WILL MOVE ACROSS NRN ONTARIO WITH ASSOCIATED COLD
FRONT MOVING ACROSS UPPER MI. STRONG SHORTWAVE NOW OVER THE PACIFIC
NW WILL ALSO SWING OUT INTO THE PLAINS TONIGHT AND THEN ROTATE INTO
THE UPPER LAKES SUN. ALTHOUGH SHORTWAVE WILL BE WEAKENING...THE
WELL-DEFINED APPEARANCE/STRONG HEIGHT FALLS PER 00Z RAOBS SUGGEST
CONTINUING TO FAVOR THE WETTER SOLUTIONS FOR SUN. MODEL CONSENSUS
DEPICTS FAIRLY STRONG DEEP LAYER QVECTOR CONVERGENCE QUICKLY LIFTING
ACROSS THE CENTRAL AND ERN FCST AREA AS VORT CENTER TRACKS ACROSS
SRN WI AND THRU NRN LWR MI. ALONG THE TRACK OF THE VORT CENTER...
STEEP MIDLEVEL LAPSE RATES IN EXCESS OF 7C/KM AND SHOWALTER INDEX
AROUND OR JUST BLO 0C ARE NOTED WHICH SUGGESTS SOME CONVECTION COULD
BE ASSOCIATED WITH SYSTEM. WILL BE SOMETHING TO KEEP IN MIND IN
LATER FCSTS IF SHORTWAVE TRACKS A LITTLE FARTHER N AS SUGGESTED BY
THE HIGH RES-ARW. IN ANY EVENT...POPS WILL SHOW A GRADIENT FROM
SLIGHT CHC NW TO LIKELY SE SUN. CLOUD COVER AND PROBABLE PCPN WILL
LIMIT TEMP RISE DESPITE MILD START TO THE DAY. EXPECT MAX TEMPS OF
MID 40S TO AROUND 50.
BRIEF SHOT OF PCPN (3-6HRS) WILL BE OUT OF THE AREA BY SUN EVENING.
BEHIND COLD FRONT...CAA AND ASSOCIATED INCREASED MIXING COULD LEAD
TO WIND GUSTS TO AROUND 40 MPH OVER THE KEWEENAW PENINSULA SUN
EVENING IN FAVORABLE WRLY FLOW (NAM/GFS BOTH SHOW 40KT WINDS WITHIN
1KFT). 850MB TEMPS BRIEFLY FALLING TO -4C WON`T BE SUFFICIENT FOR
ANY LAKE EFFECT PCPN SUN NIGHT.
MEDIUM RANGE GUIDANCE OVER THE LAST FEW DAYS HAS OCCASIONALLY
SUGGESTED POTENTIAL FOR PCPN MON WITH SHORTWAVE ENERGY LIFTING NE
FROM LONGWAVE TROF AXIS ACROSS THE WRN PLAINS. WHILE CLOSE...BULK OF
GUIDANCE SUGGESTS PCPN WILL STAY SE OF THE FCST AREA. SO AT THIS
POINT...PLAN TO MAINTAIN A DRY FCST.
NEXT SHORTWAVE OF INTEREST WILL DROP INTO THE NRN PLAINS MON NIGHT
AND THEN TRACK THRU THE WRN GREAT LAKES LATE TUE. SYSTEM LOOKS
FAIRLY STRONG WITH 500MB HEIGHT FALLS OF AT LEAST 100M...SO LOW CHC
POPS LOOK ON TRACK WITH COLD FROPA TUE. GOOD PUSH OF CAA (850MB
TEMPS FALL TO AROUND -9C TUE NIGHT) ALONG WITH TIGHT PRES GRADIENT
WILL LEAD TO GALES ACROSS LAKE SUPERIOR AS 850MB WINDS ARE FCST AT
35-45KT. FAVORABLE WNW WIND DIRECTION WILL ALSO SUPPORT GUSTS OF
40-45MPH ACROSS THE KEWEENAW AND LAKESHORE AREAS EXPOSED TO A WNW
WIND. LAKE EFFECT COULD KICK INTO HIGH GEAR TUE NIGHT/WED AS 850MB
TEMPS FALL TO AROUND -9C...BUT 00Z GFS SOUNDINGS SHOW A DRY BOUNDARY
LAYER/INVERTED-V LOOK WHICH WOULD BE A BIG NEGATIVE FOR SIGNIFICANT
LES IF THAT VERIFIES. ECMWF IS MORE BULLISH WITH PCPN DOWNWIND OF
THE LAKE. IN ANY EVENT...THIS WILL BE A PERIOD TO MONITOR FOR LAKE
EFFECT SNOW ACCUMULATIONS IN THE COMING DAYS.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
VFR CONDITIONS ARE EXPECTED THROUGH EARLY THIS EVENING AS A WEAK
HIGH PRESSURE RIDGE SLIDES THROUGH THE AREA AND WINDS BECOME SRLY
AHEAD OF LOW PRESSURE MOVING THROUGH THE NRN PLAINS. THE SRLY FLOW
AND MELTING SNOW TODAY COMBINE TO MOISTEN LOW LEVELS TONIGHT. LOWER
CLOUDS AND SOME FOG SHOULD DEVELOP BY LATE EVENING AT KSAW. SOUTH
WINDS ARE NOT FAVORABLE FOR LOW CLOUDS TO DEVELOP AT KIWD AND KCMX...
SO HAVE KEPT WITH VFR CONDITIONS. STRONG LOW-LEVEL WINDS JUST ABOVE
SHARP NEAR SFC BASED INVERSION WILL RESULT IN WIND SHEAR AT ALL SITES
BEGINNING THIS EVENING.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
ACTIVE PERIOD ON THE LAKE THROUGH MUCH OF NEXT WEEK. LOW PRESSURE
PUSHING FROM THE DAKOTAS TODAY TO ONTARIO THROUGH SUNDAY WILL BRING
A PERIOD OF STRONG SOUTHERLY WINDS TO LK SUPERIOR LATE TODAY THROUGH
SUNDAY MORNING. STRONGEST WINDS...30 KTS WITH GALE GUSTS 35-40
KTS...WILL OCCUR OVER EASTERN HALF OF LK SUPERIOR. TROUGH TIED TO
THE LOW WILL SWING ACROSS LK SUPERIOR SUNDAY AFTERNOON ALLOWING FOR
WESTERLY WINDS TO 30 KTS WITH GALE GUSTS TO 35 KTS OVR MUCH OF THE
LAKE THROUGH SUNDAY NIGHT. YET ANOTHER OPPORTUNITY FOR WESTERLY GALE
FORCE WINDS OCCURS TUESDAY NIGHT THROUGH WEDNESDAY IN WAKE OF STRONG
COLD FRONT PASSING THROUGH TUESDAY AFTN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...ROLFSON
DISCUSSION...ROLFSON
AVIATION...JLA
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
457 AM EST SAT NOV 12 2011
.SYNOPSIS...
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW FLOW OVER THE GREAT LAKES
BACKING MORE WESTERLY AS TROF EXTENDING FROM HUDSON BAY TO NEW
ENGLAND CONTINUES TO SHIFT E. UPSTREAM...A POTENT SHORTWAVE WAS
DROPPING THRU THE PACIFIC NW STATES. 00Z RAOBS REVEALED VERY
IMPRESSIVE 12HR HEIGHT FALLS OF 230M AT 500MB ASSOCIATED WITH THE
WAVE OVER WRN WA. DOWNSTREAM...A RIDGE IS SHIFTING OUT OVER THE WRN
PLAINS. AT THE SFC...LOW-LEVEL W TO SW FLOW HAS DEVELOPED OVER THE
UPPER GREAT LAKES BTWN BROAD LOW PRES FROM THE ROCKIES TO NRN
ONTARIO AND HIGH PRES OVER THE SE STATES. ONGOING MODEST WAA IS ONLY
PRODUCING SOME SCT MID AND HIGH CLOUDS ACROSS THE FCST AREA EARLY
THIS MORNING.
&&
.DISCUSSION...
THE NEXT FEW DAYS WILL FEATURE A RETURN TO ABOVE NORMAL TEMPS AS
MID/UPPER LEVEL FLOW BECOMES SOUTHWESTERLY INTO THE UPPER GREAT
LAKES. COLDER WEATHER/BLO NORMAL TEMPS WILL THEN RETURN DURING THE
MIDDLE OF THE UPCOMING WEEK. THE NEXT POTENTIAL FOR PCPN WILL BE
TIED TO POTENT SHORTWAVE NOW OVER THE PACIFIC NW.
QUIET/WARMER WEATHER EXPECTED TODAY AS WAA CONTINUES ALONG WITH A
DECENT DISPLAY OF SUNSHINE. LINGERING...MELTING SNOW COVER WILL
TEMPER WARMING SOME OVER PARTS OF THE CNTRL AND W. HIGHS MAY REACH
THE MID 40S THERE. A FEW LOCATIONS OVER THE FAR W MAY TOP OUT AROUND
50F.
LOW-LEVEL MOISTURE ADDED BY MELTING SNOW TODAY COULD LEAD TO STRATUS
AND SOME FOG LATER TONIGHT/SUN MORNING AS SUGGESTED BY SOME OF THE
NAM/GFS MOS GUIDANCE AND BY NAM MODEL OUTPUT/SREF PROBABILITIES.
OTHERWISE...EXPECT A MILD NIGHT AS SW FLOW STRENGTHENS (850MB WINDS
INCREASE TO 40-50KT) AS DEEP LOW PRES MOVES TOWARD NRN ONTARIO.
EXPECT MINS IN THE MID 30S TO LWR 40S WITH THE WARMEST READINGS IN
THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR AND DOWNWIND OF LAKE MI IN
SRLY FLOW.
ON SUN...LOW PRES WILL MOVE ACROSS NRN ONTARIO WITH ASSOCIATED COLD
FRONT MOVING ACROSS UPPER MI. STRONG SHORTWAVE NOW OVER THE PACIFIC
NW WILL ALSO SWING OUT INTO THE PLAINS TONIGHT AND THEN ROTATE INTO
THE UPPER LAKES SUN. ALTHOUGH SHORTWAVE WILL BE WEAKENING...THE
WELL-DEFINED APPEARANCE/STRONG HEIGHT FALLS PER 00Z RAOBS SUGGEST
CONTINUING TO FAVOR THE WETTER SOLUTIONS FOR SUN. MODEL CONSENSUS
DEPICTS FAIRLY STRONG DEEP LAYER QVECTOR CONVERGENCE QUICKLY LIFTING
ACROSS THE CENTRAL AND ERN FCST AREA AS VORT CENTER TRACKS ACROSS
SRN WI AND THRU NRN LWR MI. ALONG THE TRACK OF THE VORT CENTER...
STEEP MIDLEVEL LAPSE RATES IN EXCESS OF 7C/KM AND SHOWALTER INDEX
AROUND OR JUST BLO 0C ARE NOTED WHICH SUGGESTS SOME CONVECTION COULD
BE ASSOCIATED WITH SYSTEM. WILL BE SOMETHING TO KEEP IN MIND IN
LATER FCSTS IF SHORTWAVE TRACKS A LITTLE FARTHER N AS SUGGESTED BY
THE HIGH RES-ARW. IN ANY EVENT...POPS WILL SHOW A GRADIENT FROM
SLIGHT CHC NW TO LIKELY SE SUN. CLOUD COVER AND PROBABLE PCPN WILL
LIMIT TEMP RISE DESPITE MILD START TO THE DAY. EXPECT MAX TEMPS OF
MID 40S TO AROUND 50.
BRIEF SHOT OF PCPN (3-6HRS) WILL BE OUT OF THE AREA BY SUN EVENING.
BEHIND COLD FRONT...CAA AND ASSOCIATED INCREASED MIXING COULD LEAD
TO WIND GUSTS TO AROUND 40 MPH OVER THE KEWEENAW PENINSULA SUN
EVENING IN FAVORABLE WRLY FLOW (NAM/GFS BOTH SHOW 40KT WINDS WITHIN
1KFT). 850MB TEMPS BRIEFLY FALLING TO -4C WON`T BE SUFFICIENT FOR
ANY LAKE EFFECT PCPN SUN NIGHT.
MEDIUM RANGE GUIDANCE OVER THE LAST FEW DAYS HAS OCCASIONALLY
SUGGESTED POTENTIAL FOR PCPN MON WITH SHORTWAVE ENERGY LIFTING NE
FROM LONGWAVE TROF AXIS ACROSS THE WRN PLAINS. WHILE CLOSE...BULK OF
GUIDANCE SUGGESTS PCPN WILL STAY SE OF THE FCST AREA. SO AT THIS
POINT...PLAN TO MAINTAIN A DRY FCST.
NEXT SHORTWAVE OF INTEREST WILL DROP INTO THE NRN PLAINS MON NIGHT
AND THEN TRACK THRU THE WRN GREAT LAKES LATE TUE. SYSTEM LOOKS
FAIRLY STRONG WITH 500MB HEIGHT FALLS OF AT LEAST 100M...SO LOW CHC
POPS LOOK ON TRACK WITH COLD FROPA TUE. GOOD PUSH OF CAA (850MB
TEMPS FALL TO AROUND -9C TUE NIGHT) ALONG WITH TIGHT PRES GRADIENT
WILL LEAD TO GALES ACROSS LAKE SUPERIOR AS 850MB WINDS ARE FCST AT
35-45KT. FAVORABLE WNW WIND DIRECTION WILL ALSO SUPPORT GUSTS OF
40-45MPH ACROSS THE KEWEENAW AND LAKESHORE AREAS EXPOSED TO A WNW
WIND. LAKE EFFECT COULD KICK INTO HIGH GEAR TUE NIGHT/WED AS 850MB
TEMPS FALL TO AROUND -9C...BUT 00Z GFS SOUNDINGS SHOW A DRY BOUNDARY
LAYER/INVERTED-V LOOK WHICH WOULD BE A BIG NEGATIVE FOR SIGNIFICANT
LES IF THAT VERIFIES. ECMWF IS MORE BULLISH WITH PCPN DOWNWIND OF
THE LAKE. IN ANY EVENT...THIS WILL BE A PERIOD TO MONITOR FOR LAKE
EFFECT SNOW ACCUMULATIONS IN THE COMING DAYS.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE FORECAST PERIOD AS A
WEAK RIDGE SLIDES THROUGH THE AREA AND WINDS BECOME SRLY AHEAD OF
LOW PRESSURE MOVING THROUGH THE NRN PLAINS. THE SRLY FLOW WILL BRING
A RETURN OF LOW LEVEL MOISTURE LATE SATURDAY INTO SATURDAY NIGHT.
SOME LOWER CLOUDS AND FOG MAY DEVELOP BY LATE EVENING AT KSAW...BUT
SHOULD BE MORE LIKELY AFT 06Z.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
ACTIVE PERIOD ON THE LAKE THROUGH MUCH OF NEXT WEEK. LOW PRESSURE
PUSHING FROM THE DAKOTAS TODAY TO ONTARIO THROUGH SUNDAY WILL BRING
A PERIOD OF STRONG SOUTHERLY WINDS TO LK SUPERIOR LATE TODAY THROUGH
SUNDAY MORNING. STRONGEST WINDS...30 KTS WITH GALE GUSTS 35-40
KTS...WILL OCCUR OVER EASTERN HALF OF LK SUPERIOR. TROUGH TIED TO
THE LOW WILL SWING ACROSS LK SUPERIOR SUNDAY AFTERNOON ALLOWING FOR
WESTERLY WINDS TO 30 KTS WITH GALE GUSTS TO 35 KTS OVR MUCH OF THE
LAKE THROUGH SUNDAY NIGHT. YET ANOTHER OPPORTUNITY FOR WESTERLY GALE
FORCE WINDS OCCURS TUESDAY NIGHT THROUGH WEDNESDAY IN WAKE OF STRONG
COLD FRONT PASSING THROUGH TUESDAY AFTN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...NONE.
LAKE SUPERIOR...NONE.
LAKE MICHIGAN...NONE.
&&
$$
SYNOPSIS...ROLFSON
DISCUSSION...ROLFSON
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1241 PM EST FRI NOV 11 2011
UPDATED AVIATION DISCUSSION FOR 18Z TAFS
.SYNOPSIS...
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF EXTENDING FROM
HUDSON BAY TO THE MID ATLANTIC STATES...LEAVING THE UPPER LAKES
UNDER NW FLOW. UPSTREAM...A WEAK SHORTWAVE TROF IS NOTED OVER
MANITOBA AND THE DAKOTAS...AND THIS FEATURE WILL AFFECT THE UPPER
LAKES TODAY. FARTHER UPSTREAM...ANOTHER SHORTWAVE IS DROPPING DOWN
THE BRITISH COLUMBIA COAST. CLOSER TO HOME...LES IS ONGOING UNDER
CHILLY AIR MASS (00Z RAOBS SHOWED 850MB TEMPS OF -6/-7/-10C AT
KAPX/KGRB/KINL RESPECTIVELY). LES IS NOT WELL ORGANIZED INTO BANDS
DESPITE UNIDIRECTIONAL NW FLOW. ONLY ONE REAL BAND IS NOTED...AND
THAT IS DUE TO THE CONVERGENCE FROM LAND BREEZE OFF MARQUETTE
COUNTY. PERIODIC MDT/HVY INTENSITY HAS BEEN NOTED ON KMQT RADAR
IMAGERY AS CONVECTIVE LAYER IS DEEP...UP TO 10KFT MSL PER VAD WIND
PROFILE. LES IS BEGINNING TO SHOW SIGNS OF DIMINISHING AS INVERSION
IS LOWERING (LATEST VAD WIND PROFILE SHOWS TOPS AT 7-8KFT).
UPSTREAM...00Z KINL SOUNDING SHOWED SHARP INVERSION AT 850MB (AROUND
4800FT MSL). TO THE W...WAA IS UNDERWAY AHEAD OF NEXT TROF AS 850MB
TEMP AT KBIS WAS UP TO 2C AT 00Z FROM -6C AT 12Z.
&&
.DISCUSSION...
FCST FOR THE NEXT FEW DAYS WILL FEATURE A WARMING TREND AS SHORTWAVE
ENERGY DROPPING DOWN BRITISH COLUMBIA COAST AMPLIFIES A TROF OVER
THE WRN CONUS...FORCING DOWNSTREAM HEIGHT RISES/WAA THRU THE CNTRL
CONUS INTO THE GREAT LAKES. LEADING THE START OF WAA WILL BE THE
SHORTWAVE OVER MANITOBA/DAKOTAS. PRIOR TO ITS ARRIVAL...ONGOING LES
WILL CONTINUE TO WIND DOWN THIS MORNING AS INVERSION LOWERS AND
850MB TEMPS BEGIN TO RISE. ADDITIONAL ACCUMULATIONS THIS MORNING
SHOULD BE AROUND 1 INCH OVER THE NE FCST AREA...THOUGH A SPOT OR TWO
NEAR THE ONE MAIN BAND INTO ALGER COUNTY COULD SEE A COUPLE OF
INCHES. WAA ASSOCIATED WITH INCOMING SHORTWAVE WILL LIKELY GENERATE
A BAND OF PCPN AS DECENT ISENTROPIC ASCENT IS INDICATED PER 290K
SFC. THERE IS SOME QUESTION AS TO THE SRN EXTENT OF WHERE COLUMN
SATURATION WILL OCCUR FOR PCPN TO REACH THE GROUND. MOST MODELS
SUGGEST PCPN WILL ONLY BRUSH NRN UPPER MI WHILE A FEW KEEP PCPN JUST
TO THE N. GIVEN DEVELOPMENT ON UPSTREAM RADAR IMAGERY...WILL CLIP
NRN UPPER MI WITH MENTION OF -SHRASN THIS AFTN. WITH WINDS BECOMING
SSW BEFORE FORCING ARRIVES...LAKE ENHANCEMENT OFF LAKE SUPERIOR WILL
NOT BE AN ISSUE FOR UPPER MI. SSW FLOW OFF LAKE MICHIGAN AND
MARGINAL 850MB TEMPS MAY PROVIDE JUST ENOUGH LOW-LEVEL MOISTENING
FOR PCPN TO EXPAND S OVER ERN PORTIONS OF THE FCST AREA DURING THE
LATE AFTN/EARLY EVENING.
PCPN WILL EXIT TO THE E THIS EVENING WITH DRY WEATHER FOLLOWING AS
WARMING CONTINUES (850MB TEMPS BY 12Z SAT SHOULD RANGE FROM 4C W TO
1C E). TEMPS TONIGHT WILL BE VERY DEPENDENT ON CLOUD COVER...
PARTICULARLY IN THE AREAS THAT HAVE SNOW COVER. IF SKIES CLEAR...
TEMPS COULD EASILY FALL INTO THE TEENS. WITH MIXED SIGNALS ON
CLEARING...ESPECIALLY SINCE WAA COULD RESULT IN LOW CLOUDS...OPTED
FOR THE MIDDLE GROUND.
WAA CONTINUES SAT. BY EVENING...850MB TEMPS SHOULD RANGE FROM 6 TO
8C ACROSS THE FCST AREA. ALTHOUGH THERE WILL BE SOME SUNSHINE...
NAM/GFS GUIDANCE TEMPS LOOK ON THE WARM SIDE (50S) OVER THE AREAS OF
THE CNTRL AND W THAT HAVE SNOW COVER. 40S SHOULD GENERALLY BE THE
RULE. MOISTURE ADDED BY MELTING SNOW SAT COULD LEAD TO STRATUS/FOG
SAT NIGHT AS STATISTICAL GUIDANCE SUGGESTS. SHOULD BE A MILD NIGHT
SAT NIGHT COMPARED TO RECENT NIGHTS UNDER STRENGTHENING SW FLOW
(850MB WINDS INCREASE TO 40-50KT) AS LOW PRES MOVES TOWARD NRN
ONTARIO. EXPECT MINS IN THE MID 30S TO AROUND 40F WITH THE WARMEST
READINGS IN THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR. COULD BE WARMER
IF CLOUDS DEVELOP.
ON SUN...LOW PRES WILL MOVE ACROSS NRN ONTARIO WITH ASSOCIATED COLD
FRONT MOVING ACROSS UPPER MI. PIECE OF ENERGY ASSOCIATED WITH
SHORTWAVE CURRENTLY DROPPING DOWN BRITISH COLUMBIA COAST WILL ALSO
BE LIFTING NE INTO THE GREAT LAKES. GIVEN THE CURRENT WELL-DEFINED
APPEARANCE OF FEATURE ON WATER VAPOR IMAGERY...WILL LEAN TOWARD THE
WETTER SOLUTIONS FOR SUN. AS IT STANDS NOW...MODELS GENERALLY DEPICT
BEST COMBINATION OF DEEP LAYER QVECTOR CONVERGENCE AND ISENTROPIC
ASCENT OVER THE ERN FCST AREA...SO HIGHEST POPS WILL BE PAINTED IN
THAT AREA. DESPITE WARM START...PLENTY OF CLOUD COVER AND PROBABLE
PCPN WILL LIMIT TEMP RISE. UPPER 40S/AROUND 50 SHOULD BE THE RULE.
IN THE WAKE OF THE SYSTEM SUN...MEDIUM RANGE GUIDANCE GENERALLY
AGREES THAT ADDITIONAL SHORTWAVE ENERGY WILL DROP SE INTO THE NCNTRL
CONUS AND THE GREAT LAKES MON/TUE. TIMING/INTENSITY OF SPECIFIC
SHORTWAVES VARY BTWN MODELS AS WOULD BE EXPECTED AT THIS TIME RANGE.
OVERALL...PATTERN SUPPORTS LOW POPS AT A MINIMUM UNTIL DETAILS CAN
BE IRONED OUT. MIGHT SEE A DECENT PERIOD OF W TO NW FLOW LES/LAKE
ENHANCED SNOW LATER TUE INTO WED AS COLD AIR SWEEPS INTO THE UPPER
LAKES BEHIND ONE OF THE SHORTWAVES.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
A WEAKENING LOW OVER MANITOBA WILL BRING A WARM FRONT ACROSS THE
AREA LATE THIS AFTERNOON AND THIS EVENING...BRINGING LITTLE MORE
THAN A SUBTLE WIND SHIFT. WITH ANOTHER ROUND OF LIGHT SNOW SHOWERS
MAINLY NORTH AT CMX...HOWEVER EXACTLY WHERE THE SHOWERS MOVE IS IN
QUESTION SO PUT IN VCSH AT CMX. THERE IS A SMALL CHANCE THAT CEILINGS
WOULD TEMPORARILY FALL TO HIGH END MVFR AT CMX AND SAW THIS EARLY
THIS AFTERNOON AS A UPPER LEVEL DISTURBANCE MOVES TROUGH AHEAD OF
THE WARM FRONT...OTHERWISE VFR CONDITIONS CAN BE EXPECTED THROUGH
THE NEXT 24 HOURS.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR ISSUANCE/...
A RIDGE OF HIGH PRESSURE OVER LS WILL EXIT TO THE LOWER GREAT LAKES
THIS AFTERNOON. EXPECT A TROUGH OF LOW PRESSURE TO PUSH EASTWARD
ACROSS LS OVERNIGHT...AHEAD OF STRONGER LOW PRESSURE DEVELOPING TO
THE WEST. LOW PRESSURE OVER SOUTHERN SASKATCHEWAN SATURDAY WILL
CROSS THROUGH ONTARIO SUNDAY...BEFORE MOVING INTO HUDSON BAY AND
QUEBEC SUNDAY NIGHT THROUGH MUCH OF THE UPCOMING WORK WEEK...WITH A
TROUGH ACROSS LS ON SUNDAY. SW GALES NEAR 35KTS WILL BE POSSIBLE
SUNDAY AFTERNOON/SUNDAY NIGHT. A BRIEF RIDGE WILL EDGE NORTHWARD
ACROSS THE AREA MONDAY...AHEAD OF A LOW NEARING THE REGION FROM THE
WEST ON TUESDAY...WITH DECREASING WINDS. W-SW WIND GUSTS WILL ONCE
AGAIN NEAR 30KTS TUESDAY...AND NOT DIMINISHING TO AROUND 20KTS UNTIL
SOMETIME WEDNESDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...ROLFSON
DISCUSSION...ROLFSON
AVIATION...TITUS
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
612 AM EST FRI NOV 11 2011
UPDATED AVIATION DISCUSSION FOR 12Z TAFS
.SYNOPSIS...
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF EXTENDING FROM
HUDSON BAY TO THE MID ATLANTIC STATES...LEAVING THE UPPER LAKES
UNDER NW FLOW. UPSTREAM...A WEAK SHORTWAVE TROF IS NOTED OVER
MANITOBA AND THE DAKOTAS...AND THIS FEATURE WILL AFFECT THE UPPER
LAKES TODAY. FARTHER UPSTREAM...ANOTHER SHORTWAVE IS DROPPING DOWN
THE BRITISH COLUMBIA COAST. CLOSER TO HOME...LES IS ONGOING UNDER
CHILLY AIR MASS (00Z RAOBS SHOWED 850MB TEMPS OF -6/-7/-10C AT
KAPX/KGRB/KINL RESPECTIVELY). LES IS NOT WELL ORGANIZED INTO BANDS
DESPITE UNIDIRECTIONAL NW FLOW. ONLY ONE REAL BAND IS NOTED...AND
THAT IS DUE TO THE CONVERGENCE FROM LAND BREEZE OFF MARQUETTE
COUNTY. PERIODIC MDT/HVY INTENSITY HAS BEEN NOTED ON KMQT RADAR
IMAGERY AS CONVECTIVE LAYER IS DEEP...UP TO 10KFT MSL PER VAD WIND
PROFILE. LES IS BEGINNING TO SHOW SIGNS OF DIMINISHING AS INVERSION
IS LOWERING (LATEST VAD WIND PROFILE SHOWS TOPS AT 7-8KFT).
UPSTREAM...00Z KINL SOUNDING SHOWED SHARP INVERSION AT 850MB (AROUND
4800FT MSL). TO THE W...WAA IS UNDERWAY AHEAD OF NEXT TROF AS 850MB
TEMP AT KBIS WAS UP TO 2C AT 00Z FROM -6C AT 12Z.
&&
.DISCUSSION...
FCST FOR THE NEXT FEW DAYS WILL FEATURE A WARMING TREND AS SHORTWAVE
ENERGY DROPPING DOWN BRITISH COLUMBIA COAST AMPLIFIES A TROF OVER
THE WRN CONUS...FORCING DOWNSTREAM HEIGHT RISES/WAA THRU THE CNTRL
CONUS INTO THE GREAT LAKES. LEADING THE START OF WAA WILL BE THE
SHORTWAVE OVER MANITOBA/DAKOTAS. PRIOR TO ITS ARRIVAL...ONGOING LES
WILL CONTINUE TO WIND DOWN THIS MORNING AS INVERSION LOWERS AND
850MB TEMPS BEGIN TO RISE. ADDITIONAL ACCUMULATIONS THIS MORNING
SHOULD BE AROUND 1 INCH OVER THE NE FCST AREA...THOUGH A SPOT OR TWO
NEAR THE ONE MAIN BAND INTO ALGER COUNTY COULD SEE A COUPLE OF
INCHES. WAA ASSOCIATED WITH INCOMING SHORTWAVE WILL LIKELY GENERATE
A BAND OF PCPN AS DECENT ISENTROPIC ASCENT IS INDICATED PER 290K
SFC. THERE IS SOME QUESTION AS TO THE SRN EXTENT OF WHERE COLUMN
SATURATION WILL OCCUR FOR PCPN TO REACH THE GROUND. MOST MODELS
SUGGEST PCPN WILL ONLY BRUSH NRN UPPER MI WHILE A FEW KEEP PCPN JUST
TO THE N. GIVEN DEVELOPMENT ON UPSTREAM RADAR IMAGERY...WILL CLIP
NRN UPPER MI WITH MENTION OF -SHRASN THIS AFTN. WITH WINDS BECOMING
SSW BEFORE FORCING ARRIVES...LAKE ENHANCEMENT OFF LAKE SUPERIOR WILL
NOT BE AN ISSUE FOR UPPER MI. SSW FLOW OFF LAKE MICHIGAN AND
MARGINAL 850MB TEMPS MAY PROVIDE JUST ENOUGH LOW-LEVEL MOISTENING
FOR PCPN TO EXPAND S OVER ERN PORTIONS OF THE FCST AREA DURING THE
LATE AFTN/EARLY EVENING.
PCPN WILL EXIT TO THE E THIS EVENING WITH DRY WEATHER FOLLOWING AS
WARMING CONTINUES (850MB TEMPS BY 12Z SAT SHOULD RANGE FROM 4C W TO
1C E). TEMPS TONIGHT WILL BE VERY DEPENDENT ON CLOUD COVER...
PARTICULARLY IN THE AREAS THAT HAVE SNOW COVER. IF SKIES CLEAR...
TEMPS COULD EASILY FALL INTO THE TEENS. WITH MIXED SIGNALS ON
CLEARING...ESPECIALLY SINCE WAA COULD RESULT IN LOW CLOUDS...OPTED
FOR THE MIDDLE GROUND.
WAA CONTINUES SAT. BY EVENING...850MB TEMPS SHOULD RANGE FROM 6 TO
8C ACROSS THE FCST AREA. ALTHOUGH THERE WILL BE SOME SUNSHINE...
NAM/GFS GUIDANCE TEMPS LOOK ON THE WARM SIDE (50S) OVER THE AREAS OF
THE CNTRL AND W THAT HAVE SNOW COVER. 40S SHOULD GENERALLY BE THE
RULE. MOISTURE ADDED BY MELTING SNOW SAT COULD LEAD TO STRATUS/FOG
SAT NIGHT AS STATISTICAL GUIDANCE SUGGESTS. SHOULD BE A MILD NIGHT
SAT NIGHT COMPARED TO RECENT NIGHTS UNDER STRENGTHENING SW FLOW
(850MB WINDS INCREASE TO 40-50KT) AS LOW PRES MOVES TOWARD NRN
ONTARIO. EXPECT MINS IN THE MID 30S TO AROUND 40F WITH THE WARMEST
READINGS IN THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR. COULD BE WARMER
IF CLOUDS DEVELOP.
ON SUN...LOW PRES WILL MOVE ACROSS NRN ONTARIO WITH ASSOCIATED COLD
FRONT MOVING ACROSS UPPER MI. PIECE OF ENERGY ASSOCIATED WITH
SHORTWAVE CURRENTLY DROPPING DOWN BRITISH COLUMBIA COAST WILL ALSO
BE LIFTING NE INTO THE GREAT LAKES. GIVEN THE CURRENT WELL-DEFINED
APPEARANCE OF FEATURE ON WATER VAPOR IMAGERY...WILL LEAN TOWARD THE
WETTER SOLUTIONS FOR SUN. AS IT STANDS NOW...MODELS GENERALLY DEPICT
BEST COMBINATION OF DEEP LAYER QVECTOR CONVERGENCE AND ISENTROPIC
ASCENT OVER THE ERN FCST AREA...SO HIGHEST POPS WILL BE PAINTED IN
THAT AREA. DESPITE WARM START...PLENTY OF CLOUD COVER AND PROBABLE
PCPN WILL LIMIT TEMP RISE. UPPER 40S/AROUND 50 SHOULD BE THE RULE.
IN THE WAKE OF THE SYSTEM SUN...MEDIUM RANGE GUIDANCE GENERALLY
AGREES THAT ADDITIONAL SHORTWAVE ENERGY WILL DROP SE INTO THE NCNTRL
CONUS AND THE GREAT LAKES MON/TUE. TIMING/INTENSITY OF SPECIFIC
SHORTWAVES VARY BTWN MODELS AS WOULD BE EXPECTED AT THIS TIME RANGE.
OVERALL...PATTERN SUPPORTS LOW POPS AT A MINIMUM UNTIL DETAILS CAN
BE IRONED OUT. MIGHT SEE A DECENT PERIOD OF W TO NW FLOW LES/LAKE
ENHANCED SNOW LATER TUE INTO WED AS COLD AIR SWEEPS INTO THE UPPER
LAKES BEHIND ONE OF THE SHORTWAVES.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
WINDS TURNING SOUTHERLY THIS MORNING...WITH A RIDGE EXITING
OVERHEAD...WILL TEMPORARILY ANY ANY LINGERING SNOW SHOWERS.
HOWEVER...A WEAKENING LOW OVER LAKE WINNIPEG THIS MORNING WILL BRING
A WARM FRONT ACROSS THE AREA LATE THIS AFTERNOON AND THIS
EVENING...WITH LITTLE MORE THAN A WIND SHIFT. WITH ANOTHER ROUND OF
LIGHT SNOW SHOWERS MAINLY NORTH AT CMX. THERE IS A SMALL CHANCE THAT
CEILINGS WOULD TEMPORARILY FALL TO HIGH END MVFR AT CMX AND SAW THIS
EARLY THIS AFTERNOON AS A UPPER LEVEL DISTURBANCE MOVES TROUGH AHEAD
OF THE WARM FRONT...OTHERWISE VFR CONDITIONS CAN BE EXPECTED THROUGH
THE NEXT 24 HOURS.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR ISSUANCE/...
A RIDGE OF HIGH PRESSURE OVER LS WILL EXIT TO THE LOWER GREAT LAKES
THIS AFTERNOON. EXPECT A TROUGH OF LOW PRESSURE TO PUSH EASTWARD
ACROSS LS OVERNIGHT...AHEAD OF STRONGER LOW PRESSURE DEVELOPING TO
THE WEST. LOW PRESSURE OVER SOUTHERN SASKATCHEWAN SATURDAY WILL
CROSS THROUGH ONTARIO SUNDAY...BEFORE MOVING INTO HUDSON BAY AND
QUEBEC SUNDAY NIGHT THROUGH MUCH OF THE UPCOMING WORK WEEK...WITH A
TROUGH ACROSS LS ON SUNDAY. SW GALES NEAR 35KTS WILL BE POSSIBLE
SUNDAY AFTERNOON/SUNDAY NIGHT. A BRIEF RIDGE WILL EDGE NORTHWARD
ACROSS THE AREA MONDAY...AHEAD OF A LOW NEARING THE REGION FROM THE
WEST ON TUESDAY...WITH DECREASING WINDS. W-SW WIND GUSTS WILL ONCE
AGAIN NEAR 30KTS TUESDAY...AND NOT DIMINISHING TO AROUND 20KTS UNTIL
SOMETIME WEDNESDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...ROLFSON
DISCUSSION...ROLFSON
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
448 AM EST FRI NOV 11 2011
.SYNOPSIS...
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF EXTENDING FROM
HUDSON BAY TO THE MID ATLANTIC STATES...LEAVING THE UPPER LAKES
UNDER NW FLOW. UPSTREAM...A WEAK SHORTWAVE TROF IS NOTED OVER
MANITOBA AND THE DAKOTAS...AND THIS FEATURE WILL AFFECT THE UPPER
LAKES TODAY. FARTHER UPSTREAM...ANOTHER SHORTWAVE IS DROPPING DOWN
THE BRITISH COLUMBIA COAST. CLOSER TO HOME...LES IS ONGOING UNDER
CHILLY AIR MASS (00Z RAOBS SHOWED 850MB TEMPS OF -6/-7/-10C AT
KAPX/KGRB/KINL RESPECTIVELY). LES IS NOT WELL ORGANIZED INTO BANDS
DESPITE UNIDIRECTIONAL NW FLOW. ONLY ONE REAL BAND IS NOTED...AND
THAT IS DUE TO THE CONVERGENCE FROM LAND BREEZE OFF MARQUETTE
COUNTY. PERIODIC MDT/HVY INTENSITY HAS BEEN NOTED ON KMQT RADAR
IMAGERY AS CONVECTIVE LAYER IS DEEP...UP TO 10KFT MSL PER VAD WIND
PROFILE. LES IS BEGINNING TO SHOW SIGNS OF DIMINISHING AS INVERSION
IS LOWERING (LATEST VAD WIND PROFILE SHOWS TOPS AT 7-8KFT).
UPSTREAM...00Z KINL SOUNDING SHOWED SHARP INVERSION AT 850MB (AROUND
4800FT MSL). TO THE W...WAA IS UNDERWAY AHEAD OF NEXT TROF AS 850MB
TEMP AT KBIS WAS UP TO 2C AT 00Z FROM -6C AT 12Z.
&&
.DISCUSSION...
FCST FOR THE NEXT FEW DAYS WILL FEATURE A WARMING TREND AS SHORTWAVE
ENERGY DROPPING DOWN BRITISH COLUMBIA COAST AMPLIFIES A TROF OVER
THE WRN CONUS...FORCING DOWNSTREAM HEIGHT RISES/WAA THRU THE CNTRL
CONUS INTO THE GREAT LAKES. LEADING THE START OF WAA WILL BE THE
SHORTWAVE OVER MANITOBA/DAKOTAS. PRIOR TO ITS ARRIVAL...ONGOING LES
WILL CONTINUE TO WIND DOWN THIS MORNING AS INVERSION LOWERS AND
850MB TEMPS BEGIN TO RISE. ADDITIONAL ACCUMULATIONS THIS MORNING
SHOULD BE AROUND 1 INCH OVER THE NE FCST AREA...THOUGH A SPOT OR TWO
NEAR THE ONE MAIN BAND INTO ALGER COUNTY COULD SEE A COUPLE OF
INCHES. WAA ASSOCIATED WITH INCOMING SHORTWAVE WILL LIKELY GENERATE
A BAND OF PCPN AS DECENT ISENTROPIC ASCENT IS INDICATED PER 290K
SFC. THERE IS SOME QUESTION AS TO THE SRN EXTENT OF WHERE COLUMN
SATURATION WILL OCCUR FOR PCPN TO REACH THE GROUND. MOST MODELS
SUGGEST PCPN WILL ONLY BRUSH NRN UPPER MI WHILE A FEW KEEP PCPN JUST
TO THE N. GIVEN DEVELOPMENT ON UPSTREAM RADAR IMAGERY...WILL CLIP
NRN UPPER MI WITH MENTION OF -SHRASN THIS AFTN. WITH WINDS BECOMING
SSW BEFORE FORCING ARRIVES...LAKE ENHANCEMENT OFF LAKE SUPERIOR WILL
NOT BE AN ISSUE FOR UPPER MI. SSW FLOW OFF LAKE MICHIGAN AND
MARGINAL 850MB TEMPS MAY PROVIDE JUST ENOUGH LOW-LEVEL MOISTENING
FOR PCPN TO EXPAND S OVER ERN PORTIONS OF THE FCST AREA DURING THE
LATE AFTN/EARLY EVENING.
PCPN WILL EXIT TO THE E THIS EVENING WITH DRY WEATHER FOLLOWING AS
WARMING CONTINUES (850MB TEMPS BY 12Z SAT SHOULD RANGE FROM 4C W TO
1C E). TEMPS TONIGHT WILL BE VERY DEPENDENT ON CLOUD COVER...
PARTICULARLY IN THE AREAS THAT HAVE SNOW COVER. IF SKIES CLEAR...
TEMPS COULD EASILY FALL INTO THE TEENS. WITH MIXED SIGNALS ON
CLEARING...ESPECIALLY SINCE WAA COULD RESULT IN LOW CLOUDS...OPTED
FOR THE MIDDLE GROUND.
WAA CONTINUES SAT. BY EVENING...850MB TEMPS SHOULD RANGE FROM 6 TO
8C ACROSS THE FCST AREA. ALTHOUGH THERE WILL BE SOME SUNSHINE...
NAM/GFS GUIDANCE TEMPS LOOK ON THE WARM SIDE (50S) OVER THE AREAS OF
THE CNTRL AND W THAT HAVE SNOW COVER. 40S SHOULD GENERALLY BE THE
RULE. MOISTURE ADDED BY MELTING SNOW SAT COULD LEAD TO STRATUS/FOG
SAT NIGHT AS STATISTICAL GUIDANCE SUGGESTS. SHOULD BE A MILD NIGHT
SAT NIGHT COMPARED TO RECENT NIGHTS UNDER STRENGTHENING SW FLOW
(850MB WINDS INCREASE TO 40-50KT) AS LOW PRES MOVES TOWARD NRN
ONTARIO. EXPECT MINS IN THE MID 30S TO AROUND 40F WITH THE WARMEST
READINGS IN THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR. COULD BE WARMER
IF CLOUDS DEVELOP.
ON SUN...LOW PRES WILL MOVE ACROSS NRN ONTARIO WITH ASSOCIATED COLD
FRONT MOVING ACROSS UPPER MI. PIECE OF ENERGY ASSOCIATED WITH
SHORTWAVE CURRENTLY DROPPING DOWN BRITISH COLUMBIA COAST WILL ALSO
BE LIFTING NE INTO THE GREAT LAKES. GIVEN THE CURRENT WELL-DEFINED
APPEARANCE OF FEATURE ON WATER VAPOR IMAGERY...WILL LEAN TOWARD THE
WETTER SOLUTIONS FOR SUN. AS IT STANDS NOW...MODELS GENERALLY DEPICT
BEST COMBINATION OF DEEP LAYER QVECTOR CONVERGENCE AND ISENTROPIC
ASCENT OVER THE ERN FCST AREA...SO HIGHEST POPS WILL BE PAINTED IN
THAT AREA. DESPITE WARM START...PLENTY OF CLOUD COVER AND PROBABLE
PCPN WILL LIMIT TEMP RISE. UPPER 40S/AROUND 50 SHOULD BE THE RULE.
IN THE WAKE OF THE SYSTEM SUN...MEDIUM RANGE GUIDANCE GENERALLY
AGREES THAT ADDITIONAL SHORTWAVE ENERGY WILL DROP SE INTO THE NCNTRL
CONUS AND THE GREAT LAKES MON/TUE. TIMING/INTENSITY OF SPECIFIC
SHORTWAVES VARY BTWN MODELS AS WOULD BE EXPECTED AT THIS TIME RANGE.
OVERALL...PATTERN SUPPORTS LOW POPS AT A MINIMUM UNTIL DETAILS CAN
BE IRONED OUT. MIGHT SEE A DECENT PERIOD OF W TO NW FLOW LES/LAKE
ENHANCED SNOW LATER TUE INTO WED AS COLD AIR SWEEPS INTO THE UPPER
LAKES BEHIND ONE OF THE SHORTWAVES.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
AS A RIDGE BUILDS TOWARD THE AREA...ENOUGH LOW LEVEL DRYING IS
EXPECTED FOR MAINLY VFR CONDITIONS OVER THE REGION AS WINDS VEER
TOWARD SRLY. HOWEVER...LAKE CLOUDS MAY LINGER OVERNIGHT MAINLY OVER
THE KEWEENAW WHERE MVFR CIGS SHOULD BE MORE PERSISTENT. AN UPPER
LEVEL SHORTWAVE MOVING THROUGH FRIDAY WILL BRING SOME LOWERING CIGS
TO NEAR MVFR LEVELS AT KCMX AND KSAW.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR ISSUANCE/...
A RIDGE OF HIGH PRESSURE OVER LS WILL EXIT TO THE LOWER GREAT LAKES
THIS AFTERNOON. EXPECT A TROUGH OF LOW PRESSURE TO PUSH EASTWARD
ACROSS LS OVERNIGHT...AHEAD OF STRONGER LOW PRESSURE DEVELOPING TO
THE WEST. LOW PRESSURE OVER SOUTHERN SASKATCHEWAN SATURDAY WILL
CROSS THROUGH ONTARIO SUNDAY...BEFORE MOVING INTO HUDSON BAY AND
QUEBEC SUNDAY NIGHT THROUGH MUCH OF THE UPCOMING WORK WEEK...WITH A
TROUGH ACROSS LS ON SUNDAY. SW GALES NEAR 35KTS WILL BE POSSIBLE
SUNDAY AFTERNOON/SUNDAY NIGHT. A BRIEF RIDGE WILL EDGE NORTHWARD
ACROSS THE AREA MONDAY...AHEAD OF A LOW NEARING THE REGION FROM THE
WEST ON TUESDAY...WITH DECREASING WINDS. W-SW WIND GUSTS WILL ONCE
AGAIN NEAR 30KTS TUESDAY...AND NOT DIMINISHING TO AROUND 20KTS UNTIL
SOMETIME WEDNESDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...NONE.
LAKE SUPERIOR...NONE.
LAKE MICHIGAN...NONE.
&&
$$
SYNOPSIS...ROLFSON
DISCUSSION...ROLFSON
AVIATION...JLB
MARINE...KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1130 AM CST SAT NOV 12 2011
.UPDATED FOR 18Z AVIATION DISCUSSION BELOW...
.DISCUSSION...
A RATHER UNEVENTFUL FORECAST WILL CONTINUE OVER THE NEXT
WEEK...WITH THE MAIN FOCUS OF THIS FORECAST SPENT ON POPS SUNDAY
MORNING WITH THE PASSAGE OF A COLD FRONT. WILL SEE ANOTHER DAY OF
WELL ABOVE NORMAL TEMPERATURES TODAY...BEFORE TEMPS FALL BACK
CLOSER TO NORMAL/BELOW NORMAL FOR MOST OF NEXT WEEK AS A MORE
ZONAL FLOW SETS UP ACROSS THE MIDWEST.
CURRENT WATER VAPOR IMAGERY SHOWS TO WAVES OF INTEREST FOR THE
NEXT 30 HRS OR SO. THE FIRST ONE IS RATHER WEAK AND MOVING THROUGH
CO AT THE MOMENT...WITH A MUCH STRONGER WAVE NOW MOVING INTO ID.
BY THIS AFTERNOON...THE RUC HAS THE CO WAVE REACHING SW MN. WHERE
THIS WILL CAUSE TROUBLE IS WITH HIGHS FOR TODAY. H85 TEMPS BY ALL
ACCOUNTS WILL BE AROUND +10C /ABOUT 1.5 STAND DEV ABOVE
NORMAL/...WHICH UNDER CLEAR SKIES WOULD EASILY NET HIGHS IN THE
UPPER 50S TO MID 60S. HOWEVER...CO WAVE LOOKS TO BRING IN A FAIRLY
DENSE BAND OF CI/CS. GIVEN LOW SUN ANGLE THIS TIME OF YEAR AND
EXPECTED CLOUD COVER...DID GO A LITTLE BELOW GUIDANCE FOR HIGHS
TODAY...BUT FOR MANY AREAS THEY SHOULD STILL BE WITHIN 5 DEGREES
OR SO OF RECORDS. OTHER ISSUE TO WATCH TODAY WILL BE DEWPS. SAW
DEWPS YESTERDAY AFTERNOON TO THE W AND SW CRASH INTO THE TEENS /IN
FACT THEY ARE STILL THERE NOW/ AND ML DEWPS ALONG WITH FORECAST
SOUNDINGS FROM THE NAM WOULD INDICATE THAT MOST OF THE MN CWA
COULD SEE SIMILAR VALUES TODAY. DID BUMP DEWPS DOWN AS A
RESULT...BUT MAY NOT HAVE BEEN ENOUGH. WITH WINDS EXPECTED TO PICK
UP TO BETWEEN 15 TO 20 MPH AND AFTERNOON HUMIDITIES CRASHING INTO
THE 20S...WILL BE A DECENT FIRE WEATHER DAY ONCE AGAIN FOR
NOVEMBER STANDARDS.
FOR TONIGHT...CO WAVE WILL LEAVE US WITH AMPLE CLOUD COVER AS ID
WAVE AND ASSOCIATED PV PUNCH MOVE INTO THE DAKOTAS. SUB 985 MB SFC
LOW WILL BE TRACKING ACROSS THE INTERNATIONAL BORDER...WITH ITS
ASSOCIATED COLD FRONT MOVING INTO WRN MN AFTER MIDNIGHT. THE CLOUD
COVER ALONG WITH CONTINUED SRLY WINDS WILL HOLD OVERNIGHT LOWS
TONIGHT UP NEAR THE AVERAGE HIGHS FOR THIS TIME OF YEAR. PRECIP
LOOKS TO MAINLY HOLD OFF UNTIL SUNDAY MORNING...WHEN STRONG PV
ANOMALY AND ASSOCIATED PVA MOVE ACROSS SRN MN. FAIRLY GOOD
AGREEMENT AMONGST DETERMINISTIC MODES IN BAND OF SHOWERS MOVING
ACROSS SOUTH CENTRAL MN INTO WEST CENTRAL WI BETWEEN 12Z AND 18Z
SUNDAY AHEAD OF THE PV PUNCH. HOWEVER...HELD POPS BACK IN THE
30S. THERE ARE A FEW REASONS FOR GOING UNDER GUIDANCE. FIRST AND
FOREMOST...ANTECEDENT AIRMASS WILL BE EXTREMELY DRY AND ONCE AGAIN
CONSIDERABLE WORK WILL NEED TO BE DONE TO MOISTEN THE ATMO COLUMN.
WE HAVE SEEN THIS SITUATION NUMEROUS TIMES THIS FALL...AND MOST OF
THE TIME THE DRY AIR WINS OUT...ESPECIALLY WHEN THE FORCING IS
SHORT LIVED...AS THIS IS FORECAST TO BE. IN ADDITION...STRONG LLJ
/BETTER THAN 50 KTS/ AND ASSOCIATED MOISTURE TRANSPORT ARE
FORECAST TO MOVE FROM MO SAT NIGHT TO THE LK MICH REGION SUNDAY
MORNING. THE SNOW STORM THAT WAS NOT EARLIER IN THE WEEK HAD A
SIMILAR PATH TO ITS LLJ/MOISTURE TRANSPORT...AND ALL ASSOCIATED
PRECIP FELL SE OF THE MPX CWA. IF ANYTHING WERE TO FALL IN THE
AREA...AMOUNTS WOULD BE LESS THAN A TENTH OF AN INCH. IN ADDITION
LOW-LEVEL THERMAL PROFILES WOULD PRODUCE AN ALL LIQUID EVENT AS
WELL...SO REMOVED ANY RA/SN MIX MENTION.
NEXT SMALL TWEAK MADE TO THE FORECAST WAS TO ADD SOME SMALL POPS
MONDAY NIGHT INTO TUESDAY AS A RATHER STRONG SHORTWAVE AND
ASSOCIATED COLD FRONT MOVE THROUGH THE UPPER MS VALLEY. BEHIND THE
FRONT...NW FLOW WILL SET UP FOR THE TUESDAY THROUGH THURSDAY
PERIOD WITH RATHER COOL...THOUGH DRY AIR COMING IN FOR THE MIDDLE
PART OF NEXT WEEK. WITH H85 TEMPS FALLING TO AROUND -10C BY
WEDNESDAY...WILL BE A STRUGGLE TO HIT THE 40 DEGREE MARK WEDNESDAY
AND THURSDAY. FOR THE END OF THE WEEK INTO NEXT WEEKEND...
GFS/ECMWF BOTH START DIGGING A RATHER DEEP TROUGH OVER THE PAC
NW...WITH W/WSW FLOW DEVELOPING OVER THE CENTRAL CONUS. THIS WILL
HAVE TWO EFFECTS. ONE...TEMPERATURES WILL BEGIN TO REBOUND BACK TO
NEAR TO SLIGHTLY ABOVE NORMAL BY THE WEEKEND. TWO...BY THE WEEKEND
BOTH THE GFS/ECMWF ARE SPINNING UP QUITE THE IMPRESSIVE LEE SIDE
LOW OVER THE CENTRAL HIGH PLAINS. LOTS OF DISAGREEMENT ON THE
DETAILS THIS FAR OUT...BUT THERE IS THE GENERAL IDEA THAT NEXT
WEEKEND COULD BRING THE NEXT SHOT AT SEEING SOME PRECIP IN THE
AREA.
&&
.AVIATION... /18Z TAF ISSUANCE/
VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THE BULK OF THE PERIOD.
EXPECTING CLOUDS HEIGHTS TO LOWER OVER ESPECIALLY SOUTHERN PORTIONS
OF THE AREA AS SYSTEM MOVES IN LATER TONIGHT. SHOULD DROP TO 8-10K
FEET 08Z-12Z BEST SHOT OF RAIN MOVING MAINLY SOUTH OF THE TAF SITES.
WILL CONTINUE TREND OF VCSH BOTH KMSP AND KEAU FOR THE INTERIM.
WINDS EXPECTED TO INCREASE THIS AFTERNOON AND GUTS TO AROUND 20KTS
AT SOUTHERN SITES AND THEN SWITCH TO SOUTHWEST AND EVENTUALLY
WEST/NORTHWEST WITH PASSAGE OF FRONT OVERNIGHT/SUNDAY MORNING. SOME
GUSTS AROUND 20KTS POSSIBLE BEHIND COLD FRONT AS WELL. SMALL CHANCE
OF STRATOCUMULUS DECK NEAR THE KAXN AREA SUNDAY MORNING. LEFT AS
SCATTERED 1500FT BECAUSE OF LOWER CONFIDENCE.
KMSP...VFR EXPECTED THROUGH THE PERIOD. THERE IS A SMALL THREAT OF
SHOWERS 13Z-17Z SUNDAY MORNING AS FRONT MOVES THROUGH. SOUTHERLY
WINDS INCREASING TO 10 TO 15 KNOTS WITH A FEW GUSTS 18-20KTS
POSSIBLE THIS AFTERNOON. WIND SWITCHES TO MORE SOUTHWEST TO WEST
SUNDAY MORNING AND WILL LIKELY BECOME A BIT GUSTY AS WELL WITH
FRONTAL PASSAGE.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/DWE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
510 AM CST SAT NOV 12 2011
.DISCUSSION...
A RATHER UNEVENTFUL FORECAST WILL CONTINUE OVER THE NEXT
WEEK...WITH THE MAIN FOCUS OF THIS FORECAST SPENT ON POPS SUNDAY
MORNING WITH THE PASSAGE OF A COLD FRONT. WILL SEE ANOTHER DAY OF
WELL ABOVE NORMAL TEMPERATURES TODAY...BEFORE TEMPS FALL BACK
CLOSER TO NORMAL/BELOW NORMAL FOR MOST OF NEXT WEEK AS A MORE
ZONAL FLOW SETS UP ACROSS THE MIDWEST.
CURRENT WATER VAPOR IMAGERY SHOWS TO WAVES OF INTEREST FOR THE
NEXT 30 HRS OR SO. THE FIRST ONE IS RATHER WEAK AND MOVING THROUGH
CO AT THE MOMENT...WITH A MUCH STRONGER WAVE NOW MOVING INTO ID.
BY THIS AFTERNOON...THE RUC HAS THE CO WAVE REACHING SW MN. WHERE
THIS WILL CAUSE TROUBLE IS WITH HIGHS FOR TODAY. H85 TEMPS BY ALL
ACCOUNTS WILL BE AROUND +10C /ABOUT 1.5 STAND DEV ABOVE
NORMAL/...WHICH UNDER CLEAR SKIES WOULD EASILY NET HIGHS IN THE
UPPER 50S TO MID 60S. HOWEVER...CO WAVE LOOKS TO BRING IN A FAIRLY
DENSE BAND OF CI/CS. GIVEN LOW SUN ANGLE THIS TIME OF YEAR AND
EXPECTED CLOUD COVER...DID GO A LITTLE BELOW GUIDANCE FOR HIGHS
TODAY...BUT FOR MANY AREAS THEY SHOULD STILL BE WITHIN 5 DEGREES
OR SO OF RECORDS. OTHER ISSUE TO WATCH TODAY WILL BE DEWPS. SAW
DEWPS YESTERDAY AFTERNOON TO THE W AND SW CRASH INTO THE TEENS /IN
FACT THEY ARE STILL THERE NOW/ AND ML DEWPS ALONG WITH FORECAST
SOUNDINGS FROM THE NAM WOULD INDICATE THAT MOST OF THE MN CWA
COULD SEE SIMILAR VALUES TODAY. DID BUMP DEWPS DOWN AS A
RESULT...BUT MAY NOT HAVE BEEN ENOUGH. WITH WINDS EXPECTED TO PICK
UP TO BETWEEN 15 TO 20 MPH AND AFTERNOON HUMIDITIES CRASHING INTO
THE 20S...WILL BE A DECENT FIRE WEATHER DAY ONCE AGAIN FOR
NOVEMBER STANDARDS.
FOR TONIGHT...CO WAVE WILL LEAVE US WITH AMPLE CLOUD COVER AS ID
WAVE AND ASSOCIATED PV PUNCH MOVE INTO THE DAKOTAS. SUB 985 MB SFC
LOW WILL BE TRACKING ACROSS THE INTERNATIONAL BORDER...WITH ITS
ASSOCIATED COLD FRONT MOVING INTO WRN MN AFTER MIDNIGHT. THE CLOUD
COVER ALONG WITH CONTINUED SRLY WINDS WILL HOLD OVERNIGHT LOWS
TONIGHT UP NEAR THE AVERAGE HIGHS FOR THIS TIME OF YEAR. PRECIP
LOOKS TO MAINLY HOLD OFF UNTIL SUNDAY MORNING...WHEN STRONG PV
ANOMALY AND ASSOCIATED PVA MOVE ACROSS SRN MN. FAIRLY GOOD
AGREEMENT AMONGST DETERMINISTIC MODES IN BAND OF SHOWERS MOVING
ACROSS SOUTH CENTRAL MN INTO WEST CENTRAL WI BETWEEN 12Z AND 18Z
SUNDAY AHEAD OF THE PV PUNCH. HOWEVER...HELD POPS BACK IN THE
30S. THERE ARE A FEW REASONS FOR GOING UNDER GUIDANCE. FIRST AND
FOREMOST...ANTECEDENT AIRMASS WILL BE EXTREMELY DRY AND ONCE AGAIN
CONSIDERABLE WORK WILL NEED TO BE DONE TO MOISTEN THE ATMO COLUMN.
WE HAVE SEEN THIS SITUATION NUMEROUS TIMES THIS FALL...AND MOST OF
THE TIME THE DRY AIR WINS OUT...ESPECIALLY WHEN THE FORCING IS
SHORT LIVED...AS THIS IS FORECAST TO BE. IN ADDITION...STRONG LLJ
/BETTER THAN 50 KTS/ AND ASSOCIATED MOISTURE TRANSPORT ARE
FORECAST TO MOVE FROM MO SAT NIGHT TO THE LK MICH REGION SUNDAY
MORNING. THE SNOW STORM THAT WAS NOT EARLIER IN THE WEEK HAD A
SIMILAR PATH TO ITS LLJ/MOISTURE TRANSPORT...AND ALL ASSOCIATED
PRECIP FELL SE OF THE MPX CWA. IF ANYTHING WERE TO FALL IN THE
AREA...AMOUNTS WOULD BE LESS THAN A TENTH OF AN INCH. IN ADDITION
LOW-LEVEL THERMAL PROFILES WOULD PRODUCE AN ALL LIQUID EVENT AS
WELL...SO REMOVED ANY RA/SN MIX MENTION.
NEXT SMALL TWEAK MADE TO THE FORECAST WAS TO ADD SOME SMALL POPS
MONDAY NIGHT INTO TUESDAY AS A RATHER STRONG SHORTWAVE AND
ASSOCIATED COLD FRONT MOVE THROUGH THE UPPER MS VALLEY. BEHIND THE
FRONT...NW FLOW WILL SET UP FOR THE TUESDAY THROUGH THURSDAY
PERIOD WITH RATHER COOL...THOUGH DRY AIR COMING IN FOR THE MIDDLE
PART OF NEXT WEEK. WITH H85 TEMPS FALLING TO AROUND -10C BY
WEDNESDAY...WILL BE A STRUGGLE TO HIT THE 40 DEGREE MARK WEDNESDAY
AND THURSDAY. FOR THE END OF THE WEEK INTO NEXT WEEKEND...
GFS/ECMWF BOTH START DIGGING A RATHER DEEP TROUGH OVER THE PAC
NW...WITH W/WSW FLOW DEVELOPING OVER THE CENTRAL CONUS. THIS WILL
HAVE TWO EFFECTS. ONE...TEMPERATURES WILL BEGIN TO REBOUND BACK TO
NEAR TO SLIGHTLY ABOVE NORMAL BY THE WEEKEND. TWO...BY THE WEEKEND
BOTH THE GFS/ECMWF ARE SPINNING UP QUITE THE IMPRESSIVE LEE SIDE
LOW OVER THE CENTRAL HIGH PLAINS. LOTS OF DISAGREEMENT ON THE
DETAILS THIS FAR OUT...BUT THERE IS THE GENERAL IDEA THAT NEXT
WEEKEND COULD BRING THE NEXT SHOT AT SEEING SOME PRECIP IN THE
AREA.
&&
.AVIATION... /12Z TAF ISSUANCE/
VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THE BULK OF THE PERIOD.
CLOUDS AND CEILING HEIGHTS SHOULD GENERALLY BE AT OR ABOVE 10K AGL.
SOUTHERLY WINDS INCREASING 15 TO 20 KNOTS WITH HIGHER GUSTS NEAR 30
KNOTS BY MID AFTERNOON OVER THE WESTERN SECTION MN. SHORTWAVE
TROUGH OVER THE NORTHERN ROCKIES...WILL BRING SOME SCATTERED SHOWERS
TO PARTS OF SOUTHWEST MN LATER TONIGHT AND ACROSS MUCH OF THE
FORECAST AREA SUNDAY MORNING.
KMSP...VFR THROUGH THE PERIOD. THERE IS A SOME SMALL THREAT OF
SHOWERS SUNDAY MORNING. SOUTHERLY WINDS INCREASING TO 10 TO 15 KNOTS
THIS AFTERNOON.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/JM
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
408 AM CST SAT NOV 12 2011
.DISCUSSION...
A RATHER UNEVENTFUL FORECAST WILL CONTINUE OVER THE NEXT
WEEK...WITH THE MAIN FOCUS OF THIS FORECAST SPENT ON POPS SUNDAY
MORNING WITH THE PASSAGE OF A COLD FRONT. WILL SEE ANOTHER DAY OF
WELL ABOVE NORMAL TEMPERATURES TODAY...BEFORE TEMPS FALL BACK
CLOSER TO NORMAL/BELOW NORMAL FOR MOST OF NEXT WEEK AS A MORE
ZONAL FLOW SETS UP ACROSS THE MIDWEST.
CURRENT WATER VAPOR IMAGERY SHOWS TO WAVES OF INTEREST FOR THE
NEXT 30 HRS OR SO. THE FIRST ONE IS RATHER WEAK AND MOVING THROUGH
CO AT THE MOMENT...WITH A MUCH STRONGER WAVE NOW MOVING INTO ID.
BY THIS AFTERNOON...THE RUC HAS THE CO WAVE REACHING SW MN. WHERE
THIS WILL CAUSE TROUBLE IS WITH HIGHS FOR TODAY. H85 TEMPS BY ALL
ACCOUNTS WILL BE AROUND +10C /ABOUT 1.5 STAND DEV ABOVE
NORMAL/...WHICH UNDER CLEAR SKIES WOULD EASILY NET HIGHS IN THE
UPPER 50S TO MID 60S. HOWEVER...CO WAVE LOOKS TO BRING IN A FAIRLY
DENSE BAND OF CI/CS. GIVEN LOW SUN ANGLE THIS TIME OF YEAR AND
EXPECTED CLOUD COVER...DID GO A LITTLE BELOW GUIDANCE FOR HIGHS
TODAY...BUT FOR MANY AREAS THEY SHOULD STILL BE WITHIN 5 DEGREES
OR SO OF RECORDS. OTHER ISSUE TO WATCH TODAY WILL BE DEWPS. SAW
DEWPS YESTERDAY AFTERNOON TO THE W AND SW CRASH INTO THE TEENS /IN
FACT THEY ARE STILL THERE NOW/ AND ML DEWPS ALONG WITH FORECAST
SOUNDINGS FROM THE NAM WOULD INDICATE THAT MOST OF THE MN CWA
COULD SEE SIMILAR VALUES TODAY. DID BUMP DEWPS DOWN AS A
RESULT...BUT MAY NOT HAVE BEEN ENOUGH. WITH WINDS EXPECTED TO PICK
UP TO BETWEEN 15 TO 20 MPH AND AFTERNOON HUMIDITIES CRASHING INTO
THE 20S...WILL BE A DECENT FIRE WEATHER DAY ONCE AGAIN FOR
NOVEMBER STANDARDS.
FOR TONIGHT...CO WAVE WILL LEAVE US WITH AMPLE CLOUD COVER AS ID
WAVE AND ASSOCIATED PV PUNCH MOVE INTO THE DAKOTAS. SUB 985 MB SFC
LOW WILL BE TRACKING ACROSS THE INTERNATIONAL BORDER...WITH ITS
ASSOCIATED COLD FRONT MOVING INTO WRN MN AFTER MIDNIGHT. THE CLOUD
COVER ALONG WITH CONTINUED SRLY WINDS WILL HOLD OVERNIGHT LOWS
TONIGHT UP NEAR THE AVERAGE HIGHS FOR THIS TIME OF YEAR. PRECIP
LOOKS TO MAINLY HOLD OFF UNTIL SUNDAY MORNING...WHEN STRONG PV
ANOMALY AND ASSOCIATED PVA MOVE ACROSS SRN MN. FAIRLY GOOD
AGREEMENT AMONGST DETERMINISTIC MODES IN BAND OF SHOWERS MOVING
ACROSS SOUTH CENTRAL MN INTO WEST CENTRAL WI BETWEEN 12Z AND 18Z
SUNDAY AHEAD OF THE PV PUNCH. HOWEVER...HELD POPS BACK IN THE
30S. THERE ARE A FEW REASONS FOR GOING UNDER GUIDANCE. FIRST AND
FOREMOST...ANTECEDENT AIRMASS WILL BE EXTREMELY DRY AND ONCE AGAIN
CONSIDERABLE WORK WILL NEED TO BE DONE TO MOISTEN THE ATMO COLUMN.
WE HAVE SEEN THIS SITUATION NUMEROUS TIMES THIS FALL...AND MOST OF
THE TIME THE DRY AIR WINS OUT...ESPECIALLY WHEN THE FORCING IS
SHORT LIVED...AS THIS IS FORECAST TO BE. IN ADDITION...STRONG LLJ
/BETTER THAN 50 KTS/ AND ASSOCIATED MOISTURE TRANSPORT ARE
FORECAST TO MOVE FROM MO SAT NIGHT TO THE LK MICH REGION SUNDAY
MORNING. THE SNOW STORM THAT WAS NOT EARLIER IN THE WEEK HAD A
SIMILAR PATH TO ITS LLJ/MOISTURE TRANSPORT...AND ALL ASSOCIATED
PRECIP FELL SE OF THE MPX CWA. IF ANYTHING WERE TO FALL IN THE
AREA...AMOUNTS WOULD BE LESS THAN A TENTH OF AN INCH. IN ADDITION
LOW-LEVEL THERMAL PROFILES WOULD PRODUCE AN ALL LIQUID EVENT AS
WELL...SO REMOVED ANY RA/SN MIX MENTION.
NEXT SMALL TWEAK MADE TO THE FORECAST WAS TO ADD SOME SMALL POPS
MONDAY NIGHT INTO TUESDAY AS A RATHER STRONG SHORTWAVE AND
ASSOCIATED COLD FRONT MOVE THROUGH THE UPPER MS VALLEY. BEHIND THE
FRONT...NW FLOW WILL SET UP FOR THE TUESDAY THROUGH THURSDAY
PERIOD WITH RATHER COOL...THOUGH DRY AIR COMING IN FOR THE MIDDLE
PART OF NEXT WEEK. WITH H85 TEMPS FALLING TO AROUND -10C BY
WEDNESDAY...WILL BE A STRUGGLE TO HIT THE 40 DEGREE MARK WEDNESDAY
AND THURSDAY. FOR THE END OF THE WEEK INTO NEXT WEEKEND...
GFS/ECMWF BOTH START DIGGING A RATHER DEEP TROUGH OVER THE PAC
NW...WITH W/WSW FLOW DEVELOPING OVER THE CENTRAL CONUS. THIS WILL
HAVE TWO EFFECTS. ONE...TEMPERATURES WILL BEGIN TO REBOUND BACK TO
NEAR TO SLIGHTLY ABOVE NORMAL BY THE WEEKEND. TWO...BY THE WEEKEND
BOTH THE GFS/ECMWF ARE SPINNING UP QUITE THE IMPRESSIVE LEE SIDE
LOW OVER THE CENTRAL HIGH PLAINS. LOTS OF DISAGREEMENT ON THE
DETAILS THIS FAR OUT...BUT THERE IS THE GENERAL IDEA THAT NEXT
WEEKEND COULD BRING THE NEXT SHOT AT SEEING SOME PRECIP IN THE
AREA.
&&
.AVIATION... /06Z TAF ISSUANCE/
VFR THROUGH THE PERIOD WITH SOUTHERLY WINDS INCREASING TO 10 TO 15
KNOTS SATURDAY MORNING. GUSTS NEAR 20 KNOTS LIKELY FOR THE MN TAF
SITES DURING THE MID TO LATE AFTERNOON HOURS. CLOUDINESS WILL
THICKEN DURING THE DAY BUT CEILINGS WILL BE AT OR ABOVE 100
THROUGH THE END OF TAF PERIOD. BEYOND THE END OF THE TAF
(13/06)...A COLD FRONT WILL PASS ACROSS THE MN TAF SITES BETWEEN
13/06Z-12Z AND THROUGH KRNH AND KEAU BETWEEN 13/12Z-18Z. SOME
RAIN SHOWERS ARE POSSIBLE AS THE BOUNDARY MOVES THROUGH.
KMSP...VFR THROUGH THE PERIOD. SMALL THREAT AT THIS POINT FOR RAIN
SHOWERS TOWARDS DAYBREAK SUNDAY AS A COLD FRONT MOVES THROUGH.
MAIN CONCERN FOR SATURDAY IS THE WIND SPEED DURING THE AFTERNOON
AND EVENING. SPEEDS OF 12-15 KNOTS LIKELY ALONG WITH SOME GUSTS UP
TO 23 KNOTS. THE STRONGEST WINDS MAY NOT OCCUR UNTIL 22Z-23Z TIME
FRAME AND LAST INTO THE EVENING.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
MPG/RAH
AREA FORECAST DISCUSSION
NWS BILLINGS MT
322 PM MST FRI NOV 11 2011
.SHORT TERM...VALID FOR SAT AND SUN...
DOWNSLOPE FLOW PRODUCING NICE WARM UP TODAY DESPITE SOME CLOUD
COVER. HIGHS IN THE MID 50S TO LOWER 60S WILL BE COMMON ACROSS OUR
FORECAST AREA TODAY. MODELS IN GOOD AGREEMENT ON BRINGING FAIRLY
VIGOROUS...ALBEIT POSITIVE TILT TROUGH THROUGH OUR REGION TOMORROW.
THIS FEATURE IS EASILY SEEN IN WATER VAPOR IMAGERY OFF THE
SOUTHERN BRITISH COLUMBIA COAST IN THE NORTHERN SPLIT FLOW WHILE A
LARGE UPPER LOW RESTS OFF THE CALIFORNIA COAST. GFS A LITTLE MORE
AGGRESSIVE THAN NAM OR ECMWF.
THIS WEATHER SYSTEM AND ASSOCIATED FRONT WILL MOVE THROUGH OUR
FORECAST AREA SATURDAY MORNING. PROGS INDICATING FRONTOGENESIS
DEVELOPING OVER THE WESTERN AND CENTRAL ZONES BY 18Z WITH DECENT
EQUIVALENT POTENTIAL VORTICITY COINCIDING WITH THE FORCING.
STRONG COLD ADVECTION IN THE MID LEVELS WILL RAPIDLY DESTABILIZE
THE ATMOSPHERE. WINDS WILL SWITCH TO A BIT MORE NORTHERLY
COMPONENT AS FRONT MOVES THROUGH. SHOT OF STRONG LIFT FROM UPPER
DYNAMICS WILL LIKELY OVERCOME DOWNSLOPE FLOW FOR AT LEAST A SHORT
TIME. SECTIONS OF PARK COUNTY AT THE LOWER ELEVATIONS COULD SEE
TWO INCHES SATURDAY MORNING...OTHERWISE THE HIGHEST POPS OVERALL
WILL BE IN BIG HORN COUNTY AND ABSAROKAS/BEARTOOTH MOUNTAINS. ONE
OR TWO INCHES OF ACCUMULATION AT FAVORED UPSLOPE AREAS ARE
POSSIBLE THROUGH SATURDAY EVENING...WHILE THE HIGH COUNTRY IS
EXPECTED TO PICK UP 3 TO 6 INCHES.
NW FLOW REMAINS UNSTABLE EVEN AFTER THE INITIAL SHOT OF
FORCING RIGHT ON THROUGH SUNDAY NIGHT WITH 500MB HEIGHTS SLOWLY
LOWERING. THEREFORE...EXPECT AREAS OF LIGHT SNOW OR SNOW SHOWERS
TO BE FOUND ACROSS OUR FORECAST AREA AT TIMES THIS
WEEKEND...PARTICULARLY SUNDAY EVENING WHEN ANOTHER SHOT OF
UNORGANIZED ENERGY TRACKS ACROSS THE FORECAST AREA.
WIND THREAT...GAP FLOW OVER LIVINGSTON AND THE BEARTOOTH FOOTHILLS
WILL CONTINUE THROUGH TONIGHT THANKS TO A FAVORABLY ORIENTED AND
STRONG PRESSURE GRADIENT WITH STRONG SUBSIDING AIR OVER THE
MOUNTAINS. THE VERTICAL PROFILES WILL CHANGE ONCE THE FRONT COMES
THROUGH SATURDAY MORNING...BUT WESTERLY WINDS WILL CONTINUE TO BE
BRISK AFTER THE FRONTAL PASSAGE. THE OTHER AREA OF CONCERN IS THE
MOUNTAINS ABOVE RED LODGE WHERE A BRIEF MOUNTAIN WAVE TYPE
SCENARIO LOOKED POSSIBLE BASED ON WRF PROFILES. WRF IS TRYING TO
FORECAST A 65 TO 75 KT WIND AT MOUNTAIN TOP LEVELS OR AROUND 10K
FT. THE WRF ALSO SHOWS A HINT OF A CRITICAL LAYER FROM 03Z TO 06Z
TONIGHT. HOWEVER...THE GFS AND RUC DO NOT CONFIDENTLY SUPPORT MUCH
OF A CRITICAL LAYER AND I WOULD LIKE TO SEE AN INDICATION OF
BETTER MOMENTUM TRANSFER DOWNWARD. PLUS...THE JET SUPPORT IS NOT
OBVIOUS AS REGION WILL NOT BE UNDER A FAVORABLE RIGHT FRONT OR
LEFT REAR QUAD. INGREDIENTS FOR MOUNTAIN WAVE DO NOT NOT SEEM
FAVORABLE OVER RED LODGE AT THIS TIME. HOWEVER...WILL HIGHLIGHT IT
IN THE WEB GRAPHIC AND HWO AS SOME 50 MPH WINDS MAY AFFECT HIGHER
FOOTHILL LOCATIONS ABOVE RED LODGE. BT
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
MODELS REMAIN IN PRETTY GOOD AGREEMENT THROUGH THE EXTENDED PERIOD
BEGINNING MONDAY...WITH PRETTY GOOD RUN TO RUN CONSISTENCY AS
WELL. IT LOOKS LIKE A STRETCH OF UNSETTLED WEATHER IS ON TAP FOR
THE BULK OF THE PERIOD AS A BROAD UPPER LEVEL TROF EXTENDING
ACROSS THE COUNTRY KEEPS UNSTABLE NORTHWEST FLOW IN PLACE OVER US.
THE DIFFICULTY IN THIS TYPE OF FLOW CONTINUES TO BE THE TRACKING
OF SIGNIFICANT WAVES THROUGH THE REGION HOWEVER...SO POPS REMAIN
GENERALLY LOW THROUGH THE PERIOD.
EXPECT TO SEE RESPECTABLE MOUNTAIN POPS THROUGHOUT THE EXTENDED
PERIOD AS MOISTURE CONTINUES TO STREAM INTO THE REGION. MULTIPLE
SHORTWAVES WILL ROTATE THROUGH THE FLOW THROUGH WEDNESDAY AS WELL.
CURRENTLY A SIGNIFICANT WAVES APPEARS TO PUSH THROUGH THE REGION
BEGINNING MONDAY MORNING. HAVE RAISED POPS ACROSS THE
REGION...BUT ESPECIALLY WESTERN PORTIONS OF THE CWA. THIS WILL
ALLOW COLD AIR TO BEGIN TO SETTLE INTO THE REGION ONCE
AGAIN...SETTING UP WHAT APPEARS TO BE A PRETTY GOOD CHANCE FOR
OVERRUNNING THROUGH THE DAY TUESDAY...ESPECIALLY ACROSS SW
PORTIONS OF THE CWA...MAINLY FROM KBIL SOUTH AND WEST AT THIS
TIME. HAVE RAISED POPS IN THESE AREAS IN RESPONSE. THIS SYSTEM
LOOKS LIKE IT SHOULD SHIFT MORE EASTWARD THROUGH THE DAY...BUT
TIMING IS VERY QUESTIONABLE...SO HAVE KEPT POPS IN EAST A BIT
LOWER. WEDNESDAY APPEARS TO BE A SOMEWHAT TRANSITIONAL DAY...WITH
SCATTERED ACTIVITY IN ADVANCE OF DEVELOPING SHORTWAVE RIDGE THAT
WILL BRING A SHORT BREAK IN WEATHER FOR THURSDAY. THIS RESPITE WILL
BE SHORT LIVED HOWEVER...AS A STRONG PACIFIC LOW PRESSURE SYSTEM
IS PROGGED TO FINALLY MOVE OVER THE PACIFIC NORTHWEST AND MOVE
INTO CENTRAL AND EASTERN MONTANA ON FRIDAY. HAVE RAISED POPS
SIGNIFICANTLY WITH THIS SYSTEM.
AS FOR TEMP..EXPECT TO SEE COOL TEMPS THROUGH THE EXTENDED
PERIOD...BUT MAINLY ABOVE FREEZING. MONDAY AND THURSDAY WILL BE
THE WARMEST DAYS...WITH HIGHS IN THE LOW 40S. EXPECT TO SEE A
DRASTIC DROP IN TEMPS FOR FRIDAY AS PACIFIC SYSTEM MOVES INTO THE
REGION...WITH HIGHS AROUND 30 IN THE WESTERN ZONES COMING
RELATIVELY EARLY IN THE DAY. AAG
&&
.AVIATION...
STRONG GUSTY WINDS CONTINUE TO BE THE GREATEST AVIATION CONCERN
THROUGH TONIGHT...WITH PREVAILING VFR SKIES. GUSTS TO 50 KNOTS
ARE EXPECTED AROUND KLVM...AND NEAR FOOTHILLS TODAY...APPROACHING
60 KNOTS LATE THIS EVENING. GUSTY WINDS WILL EXTEND EASTWARD ACROSS
THE PLAINS TODAY...WITH GUSTS AROUND 25 KNOTS COMMON IN MANY
AREA....AND AROUND 30 KNOTS POSSIBLE AS FAR EAST AS KBIL. AAG
&&
.PRELIMINARY POINT TEMP/POPS...
SAT SUN MON TUE WED THU FRI
-----------------------------------------------------------
BIL 034/043 029/044 030/041 024/036 024/038 025/042 025/030
25/W 22/W 24/W 23/J 32/J 21/B 12/J
LVM 032/039 024/039 025/036 020/035 022/038 024/040 023/029
26/W 23/J 34/J 33/J 42/J 22/J 12/J
HDN 031/046 025/046 029/042 023/038 021/040 020/045 023/033
05/W 22/W 33/W 23/J 32/J 21/B 12/J
MLS 029/046 026/044 027/041 021/036 018/037 023/042 022/034
02/W 22/W 22/W 22/J 22/J 11/B 12/W
4BQ 029/048 024/045 026/043 021/037 021/041 021/044 022/038
03/W 31/N 22/W 22/J 22/J 11/B 12/W
BHK 026/048 024/042 024/041 022/035 019/037 022/040 019/038
02/W 31/N 22/W 12/J 22/J 11/B 12/W
SHR 028/044 022/043 025/040 021/036 019/040 020/043 021/036
04/W 21/B 22/W 33/J 32/J 21/B 12/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WIND ADVISORY IN EFFECT UNTIL 11 AM MST SATURDAY FOR ZONES
65-66.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1214 PM CST SAT NOV 12 2011
.AVIATION...18Z TAFS FOR KOMA...KLNK AND KOFK.
A WEATHER SYSTEM OVER MONTANA WILL MOVE INTO EASTERN NEBRASKA
TONIGHT AND WILL DRAG A COLD FRONT THROUGH. VFR CONDITIONS WITH MID
AND HIGH LEVEL CLOUDS WILL PUSH THROUGH THIS AFTERNOON...BUT WILL
INCREASE AGAIN TONIGHT WITH THE STORM SYSTEM. SOUTH WINDS TODAY AT
10 TO 20KT WILL SETTLE DOWN TO SOUTH OR SOUTHWEST 5 TO 15KTS THIS
EVENING. THE FRONT WILL MOVE THRU KOFK AROUND 07-08Z AND AT KOMA AND
KLNK 10-12Z. STRONGER WEST OR NORTHWEST WINDS WILL MIX DOWN AND
INCREASED WINDS TO 15 TO 30KTS BEHIND THE FRONT. INCLUDED SCATTERED
SHOWERS AT KOFK BETWEEN 08-12Z.
&&
PREV DISCUSSION.../257 AM CST SAT NOV 12 2011/
PRECIPITATION CHANCES TONIGHT...AND TEMPERATURES OVER THE NEXT
SEVERAL DAYS...ARE THE PRIMARY FORECAST CHALLENGES.
STRONG MID LEVEL LOW PRESSURE AREA THAT MOVED OUT OF THE GULF OF
ALASKA YESTERDAY WAS DIVING THROUGH WASHINGTON AND INTO IDAHO THIS
MORNING. RUC SUGGESTS TROP PRESSURES AROUND 600MB ACCOMPANIED THIS
SYSTEM...OWING TO INTENSITY OF SYSTEM. NAM SEEMED TO HAVE BEST
HANDLE ON INTENSITY...WITH ECMWF A LITTLE STRONGER AND GFS
SIGNIFICANTLY WEAKER. HOWEVER ALL MODELS WERE SIMILAR IN PROGRESSING
SYSTEM THROUGH THE ROCKIES TODAY AND ACROSS NORTHERN NEBRASKA
OVERNIGHT.
WILL HAVE A SHORT PERIOD OF INTENSE LIFT AS THIS PROGRESSIVE SYSTEM
ROLLS THROUGH. MODELS SHOW STRONG ISENTROPIC UPGLIDE NEAR AND AFTER
MIDNIGHT ACROSS NORTHEAST NEBRASKA...WITH THIS AREA SHIFTING EAST BY
12Z. MODEL MOISTURE PROFILES ARE NOT IMPRESSIVE...BUT ARE USUALLY
WAY UNDERDONE WITH STRONG NORTHWEST FLOW SYSTEMS. SO EXPECT
PRECIPITATION TO COMMENCE SOMETIME AROUND MIDNIGHT OVER THE NORTHERN
HALF OF EASTERN NEBRASKA THEN SPREADING INTO WEST CENTRAL IOWA
SHORTLY AFTER. RELATIVELY WARM LOW LEVELS INITIALLY WILL KEEP
PRECIPITATION LIQUID...BUT DYNAMIC COOLING NEAR CORE OF UPPER LOW
WILL LIKELY OVERCOME WARM SURFACE LAYER ALLOWING SNOW TO OCCUR OVER
OUR FAR NORTHERN CWA. AM NOT EXPECTING MUCH SNOWFALL GIVEN WARM
GROUND AND INITIAL LIQUID PRECIPITATION...BUT WOULD NOT BE SURPRISED
TO SEE A HALF INCH OR SO IN SOME AREAS.
AHEAD OF THIS SYSTEM...SOUTHERLY LOW LEVEL FLOW WILL HELP WARM TEMPS
TOWARD 60 AGAIN THIS AFTERNOON. MORE MID/HIGH LEVEL CLOUDS WILL CUT
DOWN ON INSOLATION...SO NOT EXPECTING HIGHS QUITE AS MILD AS FRIDAY.
RELATIVELY MILD OVERNIGHT LOWS ARE ALSO EXPECTED GIVEN CLOUD COVER
AND MIXING OF LOW LEVEL AIR.
AFTER PRECIP ENDS EARLY SUNDAY...A SWITCH TO NORTHWEST WINDS WILL
BRING COLDER AIR INTO THE REGION. A PERIOD OF GUSTY WINDS EARLY IN
THE DAY LOOKS IN ORDER BEFORE UPPER SYSTEM LIFTS TOWARD THE GREAT
LAKES. OTHERWISE...850 TEMPS DROP TO NEAR 0C JUST NORTH OF THE
NEBRASKA BORDER...AND NEAR 5C IN THE SOUTH. DECENT MIXING SHOULD
STILL PUT HIGHS IN THE 50S MOST AREAS.
ANOTHER FRONTAL SYSTEM WILL DIVE INTO THE REGION MONDAY NIGHT. AHEAD
OF IT...SOUTHWEST LOW LEVEL FLOW AND SUNSHINE WILL PUT HIGHS AGAIN
IN THE 50S. BUT HIGHS WILL STRUGGLE TO REACH 50 TUESDAY IN COLD AIR
BEHIND FRONT. A GRADUAL WARMING TREND IS EXPECTED THROUGH THE REST
OF THE WEEK AS BROAD UPPER TROUGH OVER THE CENTRAL PART OF THE
COUNTRY GRADUALLY LIFTS NORTHEAST BRINGING ZONAL THEN EVENTUALLY
SOUTHWEST FLOW ALOFT TO THE REGION.
DERGAN
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
ZAPOTOCNY
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1213 PM CST SAT NOV 12 2011
.UPDATE...
&&
.SHORT TERM...
AN UPDATED WIND ADVISORY HAS BEEN ISSUED FOR WESTERN AND PARTS OF NORTH
CENTRAL NEBRASKA FOR THE STRONG PACIFIC COLD FRONT FORECAST TO
MOVE THROUGH TONIGHT. THE RUC...HRRR...NAM AND GFS ARE ALL
SUGGESTING WIND ADVISORY CONDITIONS DEVELOPING WITH GUSTS TO 50
MPH OR STRONGER. THE HRRR AND NAM SUGGEST 58 MPH GUSTS BUT DUE THE
NOCTURNAL NATURE OF THE FRONTAL PASSAGE...A WIND ADVISORY IS IN
PLACE.
.PREV DISCUSSION... /ISSUED 1135 AM CST SAT NOV 12 2011/
UPDATE...
SHORT TERM...
BASED ON OBS IN THE WRN NEBRASKA PANHANDLE AND THE RUC...A WIND
ADVISORY HAS BEEN HOISTED FOR A FEW COUNTIES IN THE WEST.
PREV DISCUSSION... /ISSUED 755 AM CST SAT NOV 12 2011/
UPDATE...
UPDATED TO PLACE MORE WINDS IN THE FORECAST FOR TONIGHT WITH THE
COLD FRONT...COLD AIR ADVECTION...AND THE CHANCE OF PRECIPITATION
TO DRAW DOWN STRONGER GUSTS DURING THE OVERNIGHT HOURS. THIS
INDICATED IN 6Z MODEL DATA AND IN REVIEW OF MODEL SOUNDINGS.
REMAINDER OF THE FORECAST ON TRACK AND UNCHANGED.
AVIATION...
VISUAL FLIGHT RULES EXPECTED THROUGH AT LEAST 6Z SUNDAY ACROSS
WESTERN NEBRASKA. SCT-BKN CONDITIONS ABOVE 150 WILL MOVE IN FROM
THE WEST AND THICKEN AND LOWER THROUGH THE DAY. BY 6Z SUNDAY OVC100
ACROSS THE AREA WITH SCT-BKN035 EXPECTED ACROSS PORTIONS OF NORTHERN
NEBRASKA AROUND 9Z. THE LOW CLOUD DECK WILL BRING THE CHANCE OF
SNOW OR RAIN CROSSING NORTHERN SECTIONS BETWEEN 6Z AND 12Z. LIGHT
WEST WINDS THIS MORNING WILL BECOME 10-20 KNOTS TODAY AND REMAIN
10-20 OVERNIGHT AND THROUGH SUNDAY.
PREV DISCUSSION... /ISSUED 344 AM CST SAT NOV 12 2011/
SYNOPSIS...
A BROAD FLATTENING RIDGE OF HIGH PRESSURE EXTENDS EAST FROM THE
GREAT BASIN THROUGH THE NORTH CENTRAL PLAINS STATES AS INDICATED
FROM HAND ANALYSIS OF THE 12.00Z 500MB LEVEL. ALSO OF NOTE...A
CLOSED LOW CONTINUES TO SPIN JUST WEST OF KSFO WITH AN UPPER LEVEL
TROUGH ACROSS THE MID ATLANTIC/NEW ENGLAND STATES. A SECOND TROUGH
IS NOW APPARENT ACROSS THE PACIFIC NORTHWEST...WITH HEIGHT FALLS OF
230M NOTED AT KUIL. AT THE SURFACE...LIGHT SOUTHEASTERLY FLOW IS
ESTABLISHED ACROSS THE FORECAST AREA...WITH DEWPOINTS REMAINING LOW
IN THE MID TEENS. TEMPERATURES HAVE BEEN SLOW TO COOL UNDER A THIN
VEIL OF HIGH CLOUDS...WITH TEMPERATURES RUNNING FROM THE MID 20S
ACROSS THE NORTHWESTERN SAND HILLS...TO THE LOW 40S AT KTIF AND
KANW.
DISCUSSION...
FIRE WEATHER CONCERNS LEAD OFF THE DISCUSSION EARLY THIS
MORNING...THEN THE FOCUS SHIFTS TO A PASSING COLD FRONT AND
ASSOCIATED CHANCE OF PRECIPITATION OVERNIGHT TONIGHT.
REGIONAL SOUNDINGS REVEAL ABNORMALLY DRY AIR IS ONCE AGAIN IN PLACE
THROUGH THE LOW AND MID LEVELS OF THE ATMOSPHERE. THIS DRY AIR WILL
SLOWLY MODIFY THIS AFTERNOON...AS INCREASING MOISTURE ASSOCIATED
WITH THE PACIFIC NW UPPER LEVEL SYSTEM MOVES INTO THE REGION.
BUFFER SOUNDING DO SHOW THE GRADUAL INCREASE OF MOISTURE FROM TOP
DOWN...BUT CERTAINLY LIMIT THE AMOUNT OF LOW LEVEL MOISTURE DURING
PEAK HEATING. DEPENDING ON THE MODEL OF CHOICE...RELATIVE HUMIDITY
VALUES RANGE FROM THE UPPER TEENS /EURO/...TO THE UPPER 20S /NAM/
LATE THIS AFTERNOON. WILL SIDE WITH THE HIGHER RH SOLUTIONS AS A
GOOD BIT OF HIGH LEVEL CLOUDS ARE EXPECTED TODAY. GIVEN THE LOWER
SUN ANGLE AND PRESENCE OF AN UPPER LEVEL CLOUD DECK...FEEL IT WOULD
BE DIFFICULT TO REACH RED FLAG RH CRITERIA...BUT WILL NEED TO BE
MONITORED CLOSELY AS WESTERLY WINDS WILL INCREASE THIS AFTERNOON.
WIND GUSTS AOA 30 MPH WILL BE POSSIBLE ACROSS NORTHWEST NEBRASKA
THIS AFTERNOON AND ESPECIALLY THIS EVENING AS THE UPPER LEVEL SYSTEM
DRAGS A COLD FRONT THROUGH THE REGION. CAA AND HEIGHT RISES OF
2MB/HR WILL CERTAINLY CREATE FAVORABLE CONDITIONS FOR THE GUSTY
WIND. THE FRONTAL PASSAGE WILL ALSO PROVIDE A FOCUS FOR
PRECIPITATION THIS EVENING AND TONIGHT. AGAIN THE LOWER LEVELS OF
THE ATMOSPHERE ARE SUGGESTED TO BE QUITE DRY...SO PRECIPITATION THAT
FALLS WILL BE LIGHT AT BEST. MODELS DIFFER ON THE AMOUNT OF COOLING
THAT WILL TAKE PLACE...GFS REMAINS ON THE WARM SIDE...WITH H85 T/S
ABOVE 0C THROUGH MUCH OF THE NIGHT. THE NAM ON THE OTHER HAND
LOWERS TEMPERATURES ENOUGH FOR AT LEAST A MIX OF RAIN AND SNOW.
WITH ABNORMALLY WARM SURFACE TEMPERATURES FRIDAY AND THAT EXPECTED
TODAY...GROUND TEMPERATURES WILL NOT FAVOR ANY ACCUMULATION WITH THE
EXCEPTION OF GRASSY SURFACES IF SNOW WERE TO FALL. BUT GIVEN
DYNAMIC COOLING...DO EXPECT THE EVENTUAL CHANGE OVER TO
SNOW...ESPECIALLY ACROSS NORTH CENTRAL NEBRASKA...WHICH WILL BE IN
CLOSE PROXIMITY TO THE CORE OF THE UPPER LOW. THE SYSTEM QUICKLY
PULLS EAST ON SUNDAY LEAVING BEHIND BREEZY CONDITIONS EARLY...WITH
SOMEWHAT COOLER TEMPERATURES THROUGH THE DAY. EXPECTED HIGHS ON
SUNDAY WILL BE IN THE 40S AND 50S...WHICH WILL BE CLOSE TO CLIMO FOR
THIS TIME OF YEAR. ZONAL FLOW RETURNS OVER THE CENTRAL PLAINS EARLY
NEXT WEEK...WITH SEVERAL WEAK WAVES INDICATED BY THE MODELS. A
FRONT WILL USHER IN COOLER TEMPERATURES AGAIN LATE MONDAY NIGHT AND
TUESDAY...BUT A GRADUAL WARMING TREND IS EXPECTED MID TO LATE WEEK
AS ZONAL TO SOUTHWESTERLY FLOW ONCE AGAIN BECOMES ESTABLISHED.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...WIND ADVISORY FROM 8 PM CST /7 PM MST/
THIS EVENING TO 5 AM CST /4 AM MST/ SUNDAY FOR
NEZ004-022>024-035-036-056>059-069-094.
WIND ADVISORY UNTIL 4 PM MST THIS AFTERNOON FOR NEZ004-022-023-
035-094.
&&
$$
SHORT TERM/EXTENDED...CDC
AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
519 AM CST SAT NOV 12 2011
.AVIATION...
12Z TAFS FOR KOMA...KLNK AND KOFK.
VFR CONDITIONS WILL PREVAIL THROUGH THE FCST PERIOD.
DEE
&&
.PREV DISCUSSION.../257 AM CST SAT NOV 12 2011/
PRECIPITATION CHANCES TONIGHT...AND TEMPERATURES OVER THE NEXT
SEVERAL DAYS...ARE THE PRIMARY FORECAST CHALLENGES.
STRONG MID LEVEL LOW PRESSURE AREA THAT MOVED OUT OF THE GULF OF
ALASKA YESTERDAY WAS DIVING THROUGH WASHINGTON AND INTO IDAHO THIS
MORNING. RUC SUGGESTS TROP PRESSURES AROUND 600MB ACCOMPANIED THIS
SYSTEM...OWING TO INTENSITY OF SYSTEM. NAM SEEMED TO HAVE BEST
HANDLE ON INTENSITY...WITH ECMWF A LITTLE STRONGER AND GFS
SIGNIFICANTLY WEAKER. HOWEVER ALL MODELS WERE SIMILAR IN PROGRESSING
SYSTEM THROUGH THE ROCKIES TODAY AND ACROSS NORTHERN NEBRASKA
OVERNIGHT.
WILL HAVE A SHORT PERIOD OF INTENSE LIFT AS THIS PROGRESSIVE SYSTEM
ROLLS THROUGH. MODELS SHOW STRONG ISENTROPIC UPGLIDE NEAR AND AFTER
MIDNIGHT ACROSS NORTHEAST NEBRASKA...WITH THIS AREA SHIFTING EAST BY
12Z. MODEL MOISTURE PROFILES ARE NOT IMPRESSIVE...BUT ARE USUALLY
WAY UNDERDONE WITH STRONG NORTHWEST FLOW SYSTEMS. SO EXPECT
PRECIPITATION TO COMMENCE SOMETIME AROUND MIDNIGHT OVER THE NORTHERN
HALF OF EASTERN NEBRASKA THEN SPREADING INTO WEST CENTRAL IOWA
SHORTLY AFTER. RELATIVELY WARM LOW LEVELS INITIALLY WILL KEEP
PRECIPITATION LIQUID...BUT DYNAMIC COOLING NEAR CORE OF UPPER LOW
WILL LIKELY OVERCOME WARM SURFACE LAYER ALLOWING SNOW TO OCCUR OVER
OUR FAR NORTHERN CWA. AM NOT EXPECTING MUCH SNOWFALL GIVEN WARM
GROUND AND INITIAL LIQUID PRECIPITATION...BUT WOULD NOT BE SURPRISED
TO SEE A HALF INCH OR SO IN SOME AREAS.
AHEAD OF THIS SYSTEM...SOUTHERLY LOW LEVEL FLOW WILL HELP WARM TEMPS
TOWARD 60 AGAIN THIS AFTERNOON. MORE MID/HIGH LEVEL CLOUDS WILL CUT
DOWN ON INSOLATION...SO NOT EXPECTING HIGHS QUITE AS MILD AS FRIDAY.
RELATIVELY MILD OVERNIGHT LOWS ARE ALSO EXPECTED GIVEN CLOUD COVER
AND MIXING OF LOW LEVEL AIR.
AFTER PRECIP ENDS EARLY SUNDAY...A SWITCH TO NORTHWEST WINDS WILL
BRING COLDER AIR INTO THE REGION. A PERIOD OF GUSTY WINDS EARLY IN
THE DAY LOOKS IN ORDER BEFORE UPPER SYSTEM LIFTS TOWARD THE GREAT
LAKES. OTHERWISE...850 TEMPS DROP TO NEAR 0C JUST NORTH OF THE
NEBRASKA BORDER...AND NEAR 5C IN THE SOUTH. DECENT MIXING SHOULD
STILL PUT HIGHS IN THE 50S MOST AREAS.
ANOTHER FRONTAL SYSTEM WILL DIVE INTO THE REGION MONDAY NIGHT. AHEAD
OF IT...SOUTHWEST LOW LEVEL FLOW AND SUNSHINE WILL PUT HIGHS AGAIN
IN THE 50S. BUT HIGHS WILL STRUGGLE TO REACH 50 TUESDAY IN COLD AIR
BEHIND FRONT. A GRADUAL WARMING TREND IS EXPECTED THROUGH THE REST
OF THE WEEK AS BROAD UPPER TROUGH OVER THE CENTRAL PART OF THE
COUNTRY GRADUALLY LIFTS NORTHEAST BRINGING ZONAL THEN EVENTUALLY
SOUTHWEST FLOW ALOFT TO THE REGION.
DERGAN
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
257 AM CST SAT NOV 12 2011
.DISCUSSION...
PRECIPITATION CHANCES TONIGHT...AND TEMPERATURES OVER THE NEXT
SEVERAL DAYS...ARE THE PRIMARY FORECAST CHALLENGES.
STRONG MID LEVEL LOW PRESSURE AREA THAT MOVED OUT OF THE GULF OF
ALASKA YESTERDAY WAS DIVING THROUGH WASHINGTON AND INTO IDAHO THIS
MORNING. RUC SUGGESTS TROP PRESSURES AROUND 600MB ACCOMPANIED THIS
SYSTEM...OWING TO INTENSITY OF SYSTEM. NAM SEEMED TO HAVE BEST
HANDLE ON INTENSITY...WITH ECMWF A LITTLE STRONGER AND GFS
SIGNIFICANTLY WEAKER. HOWEVER ALL MODELS WERE SIMILAR IN PROGRESSING
SYSTEM THROUGH THE ROCKIES TODAY AND ACROSS NORTHERN NEBRASKA
OVERNIGHT.
WILL HAVE A SHORT PERIOD OF INTENSE LIFT AS THIS PROGRESSIVE SYSTEM
ROLLS THROUGH. MODELS SHOW STRONG ISENTROPIC UPGLIDE NEAR AND AFTER
MIDNIGHT ACROSS NORTHEAST NEBRASKA...WITH THIS AREA SHIFTING EAST BY
12Z. MODEL MOISTURE PROFILES ARE NOT IMPRESSIVE...BUT ARE USUALLY
WAY UNDERDONE WITH STRONG NORTHWEST FLOW SYSTEMS. SO EXPECT
PRECIPITATION TO COMMENCE SOMETIME AROUND MIDNIGHT OVER THE NORTHERN
HALF OF EASTERN NEBRASKA THEN SPREADING INTO WEST CENTRAL IOWA
SHORTLY AFTER. RELATIVELY WARM LOW LEVELS INITIALLY WILL KEEP
PRECIPITATION LIQUID...BUT DYNAMIC COOLING NEAR CORE OF UPPER LOW
WILL LIKELY OVERCOME WARM SURFACE LAYER ALLOWING SNOW TO OCCUR OVER
OUR FAR NORTHERN CWA. AM NOT EXPECTING MUCH SNOWFALL GIVEN WARM
GROUND AND INITIAL LIQUID PRECIPITATION...BUT WOULD NOT BE SURPRISED
TO SEE A HALF INCH OR SO IN SOME AREAS.
AHEAD OF THIS SYSTEM...SOUTHERLY LOW LEVEL FLOW WILL HELP WARM TEMPS
TOWARD 60 AGAIN THIS AFTERNOON. MORE MID/HIGH LEVEL CLOUDS WILL CUT
DOWN ON INSOLATION...SO NOT EXPECTING HIGHS QUITE AS MILD AS FRIDAY.
RELATIVELY MILD OVERNIGHT LOWS ARE ALSO EXPECTED GIVEN CLOUD COVER
AND MIXING OF LOW LEVEL AIR.
AFTER PRECIP ENDS EARLY SUNDAY...A SWITCH TO NORTHWEST WINDS WILL
BRING COLDER AIR INTO THE REGION. A PERIOD OF GUSTY WINDS EARLY IN
THE DAY LOOKS IN ORDER BEFORE UPPER SYSTEM LIFTS TOWARD THE GREAT
LAKES. OTHERWISE...850 TEMPS DROP TO NEAR 0C JUST NORTH OF THE
NEBRASKA BORDER...AND NEAR 5C IN THE SOUTH. DECENT MIXING SHOULD
STILL PUT HIGHS IN THE 50S MOST AREAS.
ANOTHER FRONTAL SYSTEM WILL DIVE INTO THE REGION MONDAY NIGHT. AHEAD
OF IT...SOUTHWEST LOW LEVEL FLOW AND SUNSHINE WILL PUT HIGHS AGAIN
IN THE 50S. BUT HIGHS WILL STRUGGLE TO REACH 50 TUESDAY IN COLD AIR
BEHIND FRONT. A GRADUAL WARMING TREND IS EXPECTED THROUGH THE REST
OF THE WEEK AS BROAD UPPER TROUGH OVER THE CENTRAL PART OF THE
COUNTRY GRADUALLY LIFTS NORTHEAST BRINGING ZONAL THEN EVENTUALLY
SOUTHWEST FLOW ALOFT TO THE REGION.
DERGAN
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK AND KOFK.
VFR CONDITIONS WILL PREVAIL FOR TAF PERIOD WITH SOUTHWESTERLY SFC
WINDS AND A SCT TO BKN DECK OF MID AND HIGH CLOUDS.
KERN
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
612 PM EST FRI NOV 11 2011
.SYNOPSIS...
SCATTERED LIGHT RAIN AND SNOW SHOWERS WILL SLOWLY WANE ACROSS THE
AREA THIS EVENING...THEN RE-GENERATE TO A LESSER EXTENT ACROSS THE
NORTHERN MOUNTAINS BY SATURDAY WITH VARIABLY CLOUDY SKIES.
EXPECT CONSIDERABLY MILDER TEMPERATURES BY SUNDAY AS HIGH
PRESSURE RETURNS WITH SOUTHERLY WINDS. CONDITIONS REMAIN
MILD...BUT TREND UNSETTLED BY THE EARLY PORTIONS OF NEXT WEEK AS A
SLOW MOVING FRONTAL SYSTEM SAGS INTO THE REGION.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 612 PM EST FRIDAY...SCATTERED RAIN/SNOW SHOWERS WILL TEND TO
DIMINISH IN OVERALL COVERAGE THIS EVENING THOUGH THESE SHOWERS
WILL NOT AMOUNT TO MUCH WITH REGARD TO QPF...A COUPLE HUNDREDTHS
OF AN INCH. CLOUD COVERAGE THIS EVENING HAS BEEN MORE VARIABLY
CLOUDY BUT STILL HAVE PLENTY OF CLOUDINESS TOWARD THE GREAT LAKES.
SEVERAL SITES STILL OCCASIONALLY SEEING SOME WIND GUSTS UP TO
AROUND 25 MPH BUT THESE WILL DIMINISH IN THE NEXT FEW HOURS. SOME
CHANGES TO MIN TEMPS MAY BE NECESSARY IN LATER UPDATES DEPENDING
ON THE DEGREE OF CLOUDS BUT NO CHANGES WERE MADE TO MINS WITH THIS
UPDATE. LOWS IN THE MID/UPPER 20S FOR THE MTNS...TO THE LOWER 30S
IN THE BROADER VALLEYS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 305 PM EST FRIDAY...GENERALLY DRY CONDITIONS ARE EXPECTED FOR
THE REMAINDER OF THE SHORT TERM FORECAST. RELIABLE SHORT RANGE 12Z
MODELS HAVE CONTINUED EARLIER TRENDS IN TRACKING TAIL END
SHORTWAVE ENERGY BUNDLE ON SATURDAY FURTHER NORTH WITH EACH
SUCCESSIVE CYCLE. THIS WOULD IN TURN LIMIT ANY ADDITIONAL RAIN OR
SNOW SHOWER THREAT GENERALLY TO THE FAR NRN MTNS DURING THE DAY.
WE`LL LIKELY STILL SEE QUITE A FEW CLOUDS AROUND HOWEVER...
ESPECIALLY WITH BROAD-SCALE WARM AIR ADVECTION DEVELOPING THROUGH
THE LOWER AND MID LEVELS AS THE DAY WEARS ON. PROGGED 925-850 MB
THERMAL PROFILES WOULD SUPPORT MILD READINGS IN THE U40S TO M50S
ACROSS THE AREA...BUT WITH ABUNDANCE OF CLOUD COVER
EXPECTED...STAYED CLOSE TO BLENDED MOS GUIDANCE OFFERING VALUES IN
THE 45-50 RANGE. WINDS TREND SOUTH/SOUTHWESTERLY DURING THE DAY
AND COULD BE GUSTY FOR A FEW HOURS DURING THE AFTERNOON.
THEN CLR/PC BY SATURDAY NIGHT UNDER BROAD SOUTH/SOUTHWESTERLY
FLOW. DUE TO VARIABLE DEGREES OF BOUNDARY LAYER
DECOUPLING OFTEN NOTED UNDER THESE TYPES OF MODEST SOUTHERLY
RETURN FLOW REGIMES...OVERNIGHT LOWS COULD BE QUITE VARIABLE
ACROSS THE AREA. HAVE THUS LEANED NEAR OR SLIGHTLY COLDER THAN
GUIDANCE ACROSS ERN VT/DACKS...AND SLIGHTLY MILDER IN THE
CHAMPLAIN/ST LAWRENCE VALLEYS.
BY SUNDAY SHORTWAVE RIDGING THEN SLIDES OFFSHORE WITH TIGHTENING
SOUTHERLY GRADIENT UNDER SUNNY/PTLY SUNNY SKIES. TEMPERATURES
CONTINUE TO MODERATE WITH HIGHS WELL INTO THE 50S...PERHAPS NEAR
60 IN CUSTOMARY MILD SPOTS. WINDS SOUTH/SOUTHWESTERLY AND GUSTY AT
TIMES.
THEREAFTER...CLOUDS WILL SLOWLY INCREASE ACROSS THE AREA OVERNIGHT
SUNDAY AS MEDIUM RANGE SOLUTIONS REMAIN IN DECENT AGREEMENT
SHOWING SLOW MOVING SFC FRONTAL ENERGY DROPPING SOUTH AND EAST
INTO THE REGION. COULD SEE A FEW SHOWERS DURING THIS PERIOD...BUT
OVERALL LACK OF MOISTURE PRECLUDES ANY POPS HIGHER THAN 30/40%
WITH THIS FEATURE. TEMPERATURES SHOULD REMAIN MILD WITH CLOUDS AND
SOUTH/SOUTHWESTERLY FLOW...MAINLY IN THE 40S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 320 PM EST FRIDAY...OVERALL LITTLE CHANGE FROM PREVIOUS
COUPLE OF FCSTS WITH REGARDS TO LARGE SCALE SYNOPTIC PATTERN AND
IMPACTS TO OUR CWA. THIS PROGRESSIVE PATTERN WL FEATURE SYSTEM
EVERY COUPLE OF DAYS...ALONG WITH MAINLY ABOVE NORMAL TEMPS. THE
SYSTEM FOR MONDAY INTO TUES IS ARRIVING 6 TO 10 HRS
QUICKER...WHICH WL RESULT IN MORE CLOUDS/PRECIP AND SLIGHTLY
COOLER TEMPS...ESPECIALLY ON TUES. BASED ON ANTICIPATED CLOUDS AND
PROGGED 925MB TEMPS BTWN 8-10C...WL MENTION HIGHS IN THE 50S FOR
BOTH DAYS. BEST CHC FOR RAIN WL BE LATE TUES AFTN INTO TUES
NIGHT...ASSOCIATED WITH SFC COLD FRNT AND WEAK SFC LOW PRES
DEVELOPING ALONG BOUNDARY. LATEST ECMWF IS MUCH MORE AGGRESSIVE
WITH DEVELOPMENT OF SFC LOW PRES ALONG BOUNDARY ASSOCIATED WITH
SOUTHERN STREAM VORT. GIVEN PROGRESSIVE MID/UPPER LVL PATTERN
ANTICIPATE WEAK AREA OF LOW PRES DEVELOPING...WHICH WL HELP TO
ENHANCE MOISTURE/CONVERGENCE AND RESULT IN A PERIOD OF RAIN LATE
TUES INTO WEDS. WL MENTION LIKELY POPS TUES AFTN AND HI CHC POPS
FOR TUES NIGHT INTO WEDS. SOME CLRING AND COOLER WX ARRIVES FOR
WEDS INTO THURS...BUT STILL SOME UNCERTAINTY WITH REGARDS TO
AMOUNT OF TROF AMPLIFICATION/LLVL CAA. WL TREND TWD THE MILDER
ECMWF SOLUTION AND MENTION TEMPS NEAR NORMAL FOR WEDS THRU
FRIDAY...AND DIS-GUARD THE COLDER GFS SOLUTION ATTM.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...MAINLY VFR CONDITIONS WL PREVAIL THRU 18Z
SATURDAY...BUT SCATTERED RAIN/SNOW SHOWERS WL RESULT IN BRIEF
PERIODS OF MVFR AND POSSIBLE IFR AT SLK BTWN 18Z-22Z THIS AFTN.
CRNT RADAR SHOWS SCATTERED MAINLY MTN SNOW/RAIN SHOWERS HAVE
DEVELOPED ASSOCIATED WITH STEEPENING LLVL LAPSE RATES FROM SFC
HEATING...UPSLOPE NW FLW...AND WEAK ELONGATED 5H VORT. THIS
ACTIVITY WL CONT THRU 22Z THIS AFTN...BUT DECREASING IN AREAL
COVERAGE/INTENSITY BY EARLY THIS EVENING. WL MENTION VCSH AT
PBG/BTV AND USE TEMPO GROUP WITH MVFR CONDITIONS AT MPV AND
POTENTIAL IFR CONDITIONS AT SLK. VIS COULD QUICKLY FALL BLW 2SM IN
THE STRONGER SNOW SHOWERS THIS AFTN AT SLK. BOTH RUC13 AND BTV4
SHOW A PERIOD OF ENHANCED UVVS AND DEEPER LAYER MOISTURE
ASSOCIATED WITH THESE SNOW SHOWERS AT SLK. OTHERWISE...INCREASE
MIXING THRU THIS AFTN WL RESULT IN GUSTY NW WINDS AT 10 TO 20
KNTS...WHICH WL DECREASE BY EVENING AND SWITCH TO THE SOUTH BY
SUNRISE. VFR CONDITIONS WL PREVAIL ON SATURDAY.
OUTLOOK 18Z SATURDAY THROUGH WEDNESDAY...
SFC HIGH PRES BUILDS INTO THE REGION FOR SAT AFTN THRU SUNDAY WITH
VFR CONDITIONS...WITH EXCEPTION OF PATCHY FOG/FZFG AT MPV/SLK BTWN
06Z-11Z SUNDAY MORNING. NEXT WEATHER SYSTEM TO IMPACT TAFS WITH
SCATTERED SHOWERS WL BE LATE MONDAY INTO TUESDAY WITH MVFR
CONDITIONS POSSIBLE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG/LOCONTO
SHORT TERM...JMG
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
315 PM EST FRI NOV 11 2011
.SYNOPSIS...
SCATTERED LIGHT RAIN AND SNOW SHOWERS WILL SLOWLY WANE ACROSS THE
AREA THIS EVENING...THEN RE-GENERATE TO A LESSER EXTENT ACROSS THE
NORTHERN MOUNTAINS BY SATURDAY WITH VARIABLY CLOUDY SKIES.
EXPECT CONSIDERABLY MILDER TEMPERATURES BY SUNDAY AS HIGH
PRESSURE RETURNS WITH SOUTHERLY WINDS. CONDITIONS REMAIN
MILD...BUT TREND UNSETTLED BY THE EARLY PORTIONS OF NEXT WEEK AS A
SLOW MOVING FRONTAL SYSTEM SAGS INTO THE REGION.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 305 PM EST FRIDAY...VARIABLY CLOUDY SKIES WILL CONTINUE
TONIGHT AS SHARP UPPER TROUGH SWINGS THROUGH THE REGION. SCATTERED
RAIN AND SNOW SHOWER ACTIVITY WILL WANE THIS EVENING AND
ESSENTIALLY END OVERNIGHT AS STEEP LAPSE RATES LESSEN WITH LOSS OF
DAYTIME HEATING. ANY ADDITIONAL PCPN AMOUNTS LIGHT AND ONLY A FEW
HUNDREDTHS AT BEST EXPECTED THROUGH 8 PM OR SO. LEANED A TAD
MILDER THAN BLENDED MOS GUIDANCE ON LOW TEMPERATURES GIVEN
LINGERING CLOUD COVER AND MARGINAL BOUNDARY LAYER MIXED PROFILES
SUGGESTING WINDS WILL REMAIN IN THE 5-10 KNOT RANGE. THIS WOULD
OFFER READINGS IN THE M-U 20S MTNS...TO LOWER 30S IN THE BROADER
VALLEYS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 305 PM EST FRIDAY...GENERALLY DRY CONDITIONS ARE EXPECTED FOR
THE REMAINDER OF THE SHORT TERM FORECAST. RELIABLE SHORT RANGE 12Z
MODELS HAVE CONTINUED EARLIER TRENDS IN TRACKING TAIL END
SHORTWAVE ENERGY BUNDLE ON SATURDAY FURTHER NORTH WITH EACH
SUCCESSIVE CYCLE. THIS WOULD IN TURN LIMIT ANY ADDITIONAL RAIN OR
SNOW SHOWER THREAT GENERALLY TO THE FAR NRN MTNS DURING THE DAY.
WE`LL LIKELY STILL SEE QUITE A FEW CLOUDS AROUND HOWEVER...
ESPECIALLY WITH BROAD-SCALE WARM AIR ADVECTION DEVELOPING THROUGH
THE LOWER AND MID LEVELS AS THE DAY WEARS ON. PROGGED 925-850 MB
THERMAL PROFILES WOULD SUPPORT MILD READINGS IN THE U40S TO M50S
ACROSS THE AREA...BUT WITH ABUNDANCE OF CLOUD COVER
EXPECTED...STAYED CLOSE TO BLENDED MOS GUIDANCE OFFERING VALUES IN
THE 45-50 RANGE. WINDS TREND SOUTH/SOUTHWESTERLY DURING THE DAY
AND COULD BE GUSTY FOR A FEW HOURS DURING THE AFTERNOON.
THEN CLR/PC BY SATURDAY NIGHT UNDER BROAD SOUTH/SOUTHWESTERLY
FLOW. DUE TO VARIABLE DEGREES OF BOUNDARY LAYER
DECOUPLING OFTEN NOTED UNDER THESE TYPES OF MODEST SOUTHERLY
RETURN FLOW REGIMES...OVERNIGHT LOWS COULD BE QUITE VARIABLE
ACROSS THE AREA. HAVE THUS LEANED NEAR OR SLIGHTLY COLDER THAN
GUIDANCE ACROSS ERN VT/DACKS...AND SLIGHTLY MILDER IN THE
CHAMPLAIN/ST LAWRENCE VALLEYS.
BY SUNDAY SHORTWAVE RIDGING THEN SLIDES OFFSHORE WITH TIGHTENING
SOUTHERLY GRADIENT UNDER SUNNY/PTLY SUNNY SKIES. TEMPERATURES
CONTINUE TO MODERATE WITH HIGHS WELL INTO THE 50S...PERHAPS NEAR
60 IN CUSTOMARY MILD SPOTS. WINDS SOUTH/SOUTHWESTERLY AND GUSTY AT
TIMES.
THEREAFTER...CLOUDS WILL SLOWLY INCREASE ACROSS THE AREA OVERNIGHT
SUNDAY AS MEDIUM RANGE SOLUTIONS REMAIN IN DECENT AGREEMENT
SHOWING SLOW MOVING SFC FRONTAL ENERGY DROPPING SOUTH AND EAST
INTO THE REGION. COULD SEE A FEW SHOWERS DURING THIS PERIOD...BUT
OVERALL LACK OF MOISTURE PRECLUDES ANY POPS HIGHER THAN 30/40%
WITH THIS FEATURE. TEMPERATURES SHOULD REMAIN MILD WITH CLOUDS AND
SOUTH/SOUTHWESTERLY FLOW...MAINLY IN THE 40S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 320 PM EST FRIDAY...OVERALL LITTLE CHANGE FROM PREVIOUS
COUPLE OF FCSTS WITH REGARDS TO LARGE SCALE SYNOPTIC PATTERN AND
IMPACTS TO OUR CWA. THIS PROGRESSIVE PATTERN WL FEATURE SYSTEM
EVERY COUPLE OF DAYS...ALONG WITH MAINLY ABOVE NORMAL TEMPS. THE
SYSTEM FOR MONDAY INTO TUES IS ARRIVING 6 TO 10 HRS
QUICKER...WHICH WL RESULT IN MORE CLOUDS/PRECIP AND SLIGHTLY
COOLER TEMPS...ESPECIALLY ON TUES. BASED ON ANTICIPATED CLOUDS AND
PROGGED 925MB TEMPS BTWN 8-10C...WL MENTION HIGHS IN THE 50S FOR
BOTH DAYS. BEST CHC FOR RAIN WL BE LATE TUES AFTN INTO TUES
NIGHT...ASSOCIATED WITH SFC COLD FRNT AND WEAK SFC LOW PRES
DEVELOPING ALONG BOUNDARY. LATEST ECMWF IS MUCH MORE AGGRESSIVE
WITH DEVELOPMENT OF SFC LOW PRES ALONG BOUNDARY ASSOCIATED WITH
SOUTHERN STREAM VORT. GIVEN PROGRESSIVE MID/UPPER LVL PATTERN
ANTICIPATE WEAK AREA OF LOW PRES DEVELOPING...WHICH WL HELP TO
ENHANCE MOISTURE/CONVERGENCE AND RESULT IN A PERIOD OF RAIN LATE
TUES INTO WEDS. WL MENTION LIKELY POPS TUES AFTN AND HI CHC POPS
FOR TUES NIGHT INTO WEDS. SOME CLRING AND COOLER WX ARRIVES FOR
WEDS INTO THURS...BUT STILL SOME UNCERTAINTY WITH REGARDS TO
AMOUNT OF TROF AMPLIFICATION/LLVL CAA. WL TREND TWD THE MILDER
ECMWF SOLUTION AND MENTION TEMPS NEAR NORMAL FOR WEDS THRU
FRIDAY...AND DIS-GUARD THE COLDER GFS SOLUTION ATTM.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...MAINLY VFR CONDITIONS WL PREVAIL THRU 18Z
SATURDAY...BUT SCATTERED RAIN/SNOW SHOWERS WL RESULT IN BRIEF
PERIODS OF MVFR AND POSSIBLE IFR AT SLK BTWN 18Z-22Z THIS AFTN.
CRNT RADAR SHOWS SCATTERED MAINLY MTN SNOW/RAIN SHOWERS HAVE
DEVELOPED ASSOCIATED WITH STEEPENING LLVL LAPSE RATES FROM SFC
HEATING...UPSLOPE NW FLW...AND WEAK ELONGATED 5H VORT. THIS
ACTIVITY WL CONT THRU 22Z THIS AFTN...BUT DECREASING IN AREAL
COVERAGE/INTENSITY BY EARLY THIS EVENING. WL MENTION VCSH AT
PBG/BTV AND USE TEMPO GROUP WITH MVFR CONDITIONS AT MPV AND
POTENTIAL IFR CONDITIONS AT SLK. VIS COULD QUICKLY FALL BLW 2SM IN
THE STRONGER SNOW SHOWERS THIS AFTN AT SLK. BOTH RUC13 AND BTV4
SHOW A PERIOD OF ENHANCED UVVS AND DEEPER LAYER MOISTURE
ASSOCIATED WITH THESE SNOW SHOWERS AT SLK. OTHERWISE...INCREASE
MIXING THRU THIS AFTN WL RESULT IN GUSTY NW WINDS AT 10 TO 20
KNTS...WHICH WL DECREASE BY EVENING AND SWITCH TO THE SOUTH BY
SUNRISE. VFR CONDITIONS WL PREVAIL ON SATURDAY.
OUTLOOK 18Z SATURDAY THROUGH WEDNESDAY...
SFC HIGH PRES BUILDS INTO THE REGION FOR SAT AFTN THRU SUNDAY WITH
VFR CONDITIONS...WITH EXCEPTION OF PATCHY FOG/FZFG AT MPV/SLK BTWN
06Z-11Z SUNDAY MORNING. NEXT WEATHER SYSTEM TO IMPACT TAFS WITH
SCATTERED SHOWERS WL BE LATE MONDAY INTO TUESDAY WITH MVFR
CONDITIONS POSSIBLE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG
SHORT TERM...JMG
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
305 PM EST FRI NOV 11 2011
.SYNOPSIS...
SCATTERED LIGHT RAIN AND SNOW SHOWERS WILL SLOWLY WANE ACROSS THE
AREA THIS EVENING...THEN RE-GENERATE TO A LESSER EXTENT ACROSS THE
NORTHERN MOUNTAINS BY SATURDAY WITH VARIABLY CLOUDY SKIES.
EXPECT CONSIDERABLY MILDER TEMPERATURES BY SUNDAY AS HIGH
PRESSURE RETURNS WITH SOUTHERLY WINDS. CONDITIONS REMAIN
MILD...BUT TREND UNSETTLED BY THE EARLY PORTIONS OF NEXT WEEK AS A
SLOW MOVING FRONTAL SYSTEM SAGS INTO THE REGION.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 305 PM EST FRIDAY...VARIABLY CLOUDY SKIES WILL CONTINUE
TONIGHT AS SHARP UPPER TROUGH SWINGS THROUGH THE REGION. SCATTERED
RAIN AND SNOW SHOWER ACTIVITY WILL WANE THIS EVENING AND
ESSENTIALLY END OVERNIGHT AS STEEP LAPSE RATES LESSEN WITH LOSS OF
DAYTIME HEATING. ANY ADDITIONAL PCPN AMOUNTS LIGHT AND ONLY A FEW
HUNDREDTHS AT BEST EXPECTED THROUGH 8 PM OR SO. LEANED A TAD
MILDER THAN BLENDED MOS GUIDANCE ON LOW TEMPERATURES GIVEN
LINGERING CLOUD COVER AND MARGINAL BOUNDARY LAYER MIXED PROFILES
SUGGESTING WINDS WILL REMAIN IN THE 5-10 KNOT RANGE. THIS WOULD
OFFER READINGS IN THE M-U 20S MTNS...TO LOWER 30S IN THE BROADER
VALLEYS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 305 PM EST FRIDAY...GENERALLY DRY CONDITIONS ARE EXPECTED FOR
THE REMAINDER OF THE SHORT TERM FORECAST. RELIABLE SHORT RANGE 12Z
MODELS HAVE CONTINUED EARLIER TRENDS IN TRACKING TAIL END
SHORTWAVE ENERGY BUNDLE ON SATURDAY FURTHER NORTH WITH EACH
SUCCESSIVE CYCLE. THIS WOULD IN TURN LIMIT ANY ADDITIONAL RAIN OR
SNOW SHOWER THREAT GENERALLY TO THE FAR NRN MTNS DURING THE DAY.
WE`LL LIKELY STILL SEE QUITE A FEW CLOUDS AROUND HOWEVER...
ESPECIALLY WITH BROAD-SCALE WARM AIR ADVECTION DEVELOPING THROUGH
THE LOWER AND MID LEVELS AS THE DAY WEARS ON. PROGGED 925-850 MB
THERMAL PROFILES WOULD SUPPORT MILD READINGS IN THE U40S TO M50S
ACROSS THE AREA...BUT WITH ABUNDANCE OF CLOUD COVER
EXPECTED...STAYED CLOSE TO BLENDED MOS GUIDANCE OFFERING VALUES IN
THE 45-50 RANGE. WINDS TREND SOUTH/SOUTHWESTERLY DURING THE DAY
AND COULD BE GUSTY FOR A FEW HOURS DURING THE AFTERNOON.
THEN CLR/PC BY SATURDAY NIGHT UNDER BROAD SOUTH/SOUTHWESTERLY
FLOW. DUE TO VARIABLE DEGREES OF BOUNDARY LAYER
DECOUPLING OFTEN NOTED UNDER THESE TYPES OF MODEST SOUTHERLY
RETURN FLOW REGIMES...OVERNIGHT LOWS COULD BE QUITE VARIABLE
ACROSS THE AREA. HAVE THUS LEANED NEAR OR SLIGHTLY COLDER THAN
GUIDANCE ACROSS ERN VT/DACKS...AND SLIGHTLY MILDER IN THE
CHAMPLAIN/ST LAWRENCE VALLEYS.
BY SUNDAY SHORTWAVE RIDGING THEN SLIDES OFFSHORE WITH TIGHTENING
SOUTHERLY GRADIENT UNDER SUNNY/PTLY SUNNY SKIES. TEMPERATURES
CONTINUE TO MODERATE WITH HIGHS WELL INTO THE 50S...PERHAPS NEAR
60 IN CUSTOMARY MILD SPOTS. WINDS SOUTH/SOUTHWESTERLY AND GUSTY AT
TIMES.
THEREAFTER...CLOUDS WILL SLOWLY INCREASE ACROSS THE AREA OVERNIGHT
SUNDAY AS MEDIUM RANGE SOLUTIONS REMAIN IN DECENT AGREEMENT
SHOWING SLOW MOVING SFC FRONTAL ENERGY DROPPING SOUTH AND EAST
INTO THE REGION. COULD SEE A FEW SHOWERS DURING THIS PERIOD...BUT
OVERALL LACK OF MOISTURE PRECLUDES ANY POPS HIGHER THAN 30/40%
WITH THIS FEATURE. TEMPERATURES SHOULD REMAIN MILD WITH CLOUDS AND
SOUTH/SOUTHWESTERLY FLOW...MAINLY IN THE 40S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 400 AM EST FRIDAY...SOUTHWEST FLOW ALOFT WILL CREATE A
SOMEWHAT ACTIVE PATTERN IN THE EXTENDED FORECAST PERIOD...SUNDAY
NIGHT THROUGH THURSDAY. HOWEVER...NONE OF THE SYSTEMS MOVING
THROUGH THE SOUTHWEST FLOW WILL BE STRONG. FIRST SYSTEM MOVES
INTO THE AREA LATE SUNDAY NIGHT INTO MONDAY FOR A CHANCE OF
SHOWERS...FOLLOWED BY ANOTHER SYSTEM ON TUESDAY AND TUESDAY
NIGHT. THIS FEATURE APPEARS TO HAVE THE BEST CHANCE OF PROVIDING
WIDESPREAD RAIN TO THE AREA. LASTLY A COUPLE OF SHORTWAVE TROUGHS
WILL MOVE ACROSS THE REGION LATER WEDNESDAY INTO THURSDAY FOR MORE
CHANCES OF SHOWERS. TEMPERATURES AT THE START OF THE PERIOD WILL
BE ABOVE NORMAL...THEN TREND TOWARD SEASONAL NORMALS BY THE LATTER
HALF OF THE PERIOD.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...MAINLY VFR CONDITIONS WL PREVAIL THRU 18Z
SATURDAY...BUT SCATTERED RAIN/SNOW SHOWERS WL RESULT IN BRIEF
PERIODS OF MVFR AND POSSIBLE IFR AT SLK BTWN 18Z-22Z THIS AFTN.
CRNT RADAR SHOWS SCATTERED MAINLY MTN SNOW/RAIN SHOWERS HAVE
DEVELOPED ASSOCIATED WITH STEEPENING LLVL LAPSE RATES FROM SFC
HEATING...UPSLOPE NW FLW...AND WEAK ELONGATED 5H VORT. THIS
ACTIVITY WL CONT THRU 22Z THIS AFTN...BUT DECREASING IN AREAL
COVERAGE/INTENSITY BY EARLY THIS EVENING. WL MENTION VCSH AT
PBG/BTV AND USE TEMPO GROUP WITH MVFR CONDITIONS AT MPV AND
POTENTIAL IFR CONDITIONS AT SLK. VIS COULD QUICKLY FALL BLW 2SM IN
THE STRONGER SNOW SHOWERS THIS AFTN AT SLK. BOTH RUC13 AND BTV4
SHOW A PERIOD OF ENHANCED UVVS AND DEEPER LAYER MOISTURE
ASSOCIATED WITH THESE SNOW SHOWERS AT SLK. OTHERWISE...INCREASE
MIXING THRU THIS AFTN WL RESULT IN GUSTY NW WINDS AT 10 TO 20
KNTS...WHICH WL DECREASE BY EVENING AND SWITCH TO THE SOUTH BY
SUNRISE. VFR CONDITIONS WL PREVAIL ON SATURDAY.
OUTLOOK 18Z SATURDAY THROUGH WEDNESDAY...
SFC HIGH PRES BUILDS INTO THE REGION FOR SAT AFTN THRU SUNDAY WITH
VFR CONDITIONS...WITH EXCEPTION OF PATCHY FOG/FZFG AT MPV/SLK BTWN
06Z-11Z SUNDAY MORNING. NEXT WEATHER SYSTEM TO IMPACT TAFS WITH
SCATTERED SHOWERS WL BE LATE MONDAY INTO TUESDAY WITH MVFR
CONDITIONS POSSIBLE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG
SHORT TERM...JMG
LONG TERM...EVENSON
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1244 PM EST FRI NOV 11 2011
.SYNOPSIS...
AS AN UPPER TROUGH SWINGS THROUGH THE REGION TODAY...GENERALLY
CLOUDY SKIES AND MORE SEASONAL TEMPERATURES ARE EXPECTED...ALONG
WITH SOME SCATTERED VALLEY RAIN AND MOUNTAIN SNOW SHOWERS.
GENERALLY DRY CONDITIONS ARE EXPECTED GOING INTO THE WEEKEND...WITH
WEAK HIGH PRESSURE BUILDING INTO THE REGION...THOUGH A WEAK UPPER
DISTURBANCE WILL KEEP A CHANCE OF PRECIPITATION ALONG THE CANADIAN
BORDER ON SATURDAY. TEMPERATURES WILL MODERATE TO ABOVE NORMAL
LEVELS AGAIN BY SUNDAY INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1214 PM EST FRIDAY...QUICK UPDATE TO MASSAGE POPS/TEMPS AT
THE NOISE LEVEL..REST OF FCST UNCHANGED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
AS OF 400 AM EST FRIDAY...GENERALLY DRY CONDITIONS ARE EXPECTED
FOR THE SHORT TERM PERIOD THROUGH THE WEEKEND WITH HIGH PRESSURE
DEVELOPING ACROSS THE MID-ATLANTIC AND SOUTHEAST STATES
SATURDAY...AND PUSHING OFF THE ATLANTIC COAST ON SUNDAY. THE
NORTH COUNTRY WILL BE ON THE NORTHERN FRINGE OF THIS HIGH...WITH
GENERALLY WESTERLY FLOW ALOFT ON SATURDAY...TURNING SOUTHWESTERLY
ON SUNDAY. A WEAK DISTURBANCE WILL TRACK JUST NORTH OF THE
CANADIAN BORDER ON SATURDAY...WHICH MAY SPARK A FEW HIGHER
ELEVATION RAIN/SNOW SHOWERS ACROSS NORTHERN LOCALES...BUT THE
MAJORITY OF THE AREA SHOULD REMAIN DRY. TEMPERATURES WILL REMAIN
SEASONAL TONIGHT THROUGH SATURDAY NIGHT WITH LOWS GENERALLY IN
THE UPPER 20 TO MID 30S...AND HIGHS IN THE 40S. BUT BY
SUNDAY...SOUTHERLY FLOW OUT AHEAD OF AN APPROACHING SYSTEM WILL
WARM TEMPS BACK ABOVE NORMAL INTO THE MID 50S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 400 AM EST FRIDAY...SOUTHWEST FLOW ALOFT WILL CREATE A
SOMEWHAT ACTIVE PATTERN IN THE EXTENDED FORECAST PERIOD...SUNDAY
NIGHT THROUGH THURSDAY. HOWEVER...NONE OF THE SYSTEMS MOVING
THROUGH THE SOUTHWEST FLOW WILL BE STRONG. FIRST SYSTEM MOVES
INTO THE AREA LATE SUNDAY NIGHT INTO MONDAY FOR A CHANCE OF
SHOWERS...FOLLOWED BY ANOTHER SYSTEM ON TUESDAY AND TUESDAY
NIGHT. THIS FEATURE APPEARS TO HAVE THE BEST CHANCE OF PROVIDING
WIDESPREAD RAIN TO THE AREA. LASTLY A COUPLE OF SHORTWAVE TROUGHS
WILL MOVE ACROSS THE REGION LATER WEDNESDAY INTO THURSDAY FOR MORE
CHANCES OF SHOWERS. TEMPERATURES AT THE START OF THE PERIOD WILL
BE ABOVE NORMAL...THEN TREND TOWARD SEASONAL NORMALS BY THE LATTER
HALF OF THE PERIOD.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...MAINLY VFR CONDITIONS WL PREVAIL THRU 18Z
SATURDAY...BUT SCATTERED RAIN/SNOW SHOWERS WL RESULT IN BRIEF
PERIODS OF MVFR AND POSSIBLE IFR AT SLK BTWN 18Z-22Z THIS AFTN.
CRNT RADAR SHOWS SCATTERED MAINLY MTN SNOW/RAIN SHOWERS HAVE
DEVELOPED ASSOCIATED WITH STEEPENING LLVL LAPSE RATES FROM SFC
HEATING...UPSLOPE NW FLW...AND WEAK ELONGATED 5H VORT. THIS
ACTIVITY WL CONT THRU 22Z THIS AFTN...BUT DECREASING IN AREAL
COVERAGE/INTENSITY BY EARLY THIS EVENING. WL MENTION VCSH AT
PBG/BTV AND USE TEMPO GROUP WITH MVFR CONDITIONS AT MPV AND
POTENTIAL IFR CONDITIONS AT SLK. VIS COULD QUICKLY FALL BLW 2SM IN
THE STRONGER SNOW SHOWERS THIS AFTN AT SLK. BOTH RUC13 AND BTV4
SHOW A PERIOD OF ENHANCED UVVS AND DEEPER LAYER MOISTURE
ASSOCIATED WITH THESE SNOW SHOWERS AT SLK. OTHERWISE...INCREASE
MIXING THRU THIS AFTN WL RESULT IN GUSTY NW WINDS AT 10 TO 20
KNTS...WHICH WL DECREASE BY EVENING AND SWITCH TO THE SOUTH BY
SUNRISE. VFR CONDITIONS WL PREVAIL ON SATURDAY.
OUTLOOK 18Z SATURDAY THROUGH WEDNESDAY...
SFC HIGH PRES BUILDS INTO THE REGION FOR SAT AFTN THRU SUNDAY WITH
VFR CONDITIONS...WITH EXCEPTION OF PATCHY FOG/FZFG AT MPV/SLK BTWN
06Z-11Z SUNDAY MORNING. NEXT WEATHER SYSTEM TO IMPACT TAFS WITH
SCATTERED SHOWERS WL BE LATE MONDAY INTO TUESDAY WITH MVFR
CONDITIONS POSSIBLE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LAHIFF
NEAR TERM...JMG
SHORT TERM...LAHIFF
LONG TERM...EVENSON
AVIATION...TABER
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
851 AM CST SAT NOV 12 2011
.UPDATE...
QUICK UPDATE TO REMOVE MENTION OF BLOWING DUST ON THE CAPROCK
THIS AFTERNOON. 12Z NAM AND RUC DATA CONTINUE TO PAINT REDUCED
GRADIENT FLOW OVER MUCH OF THE SOUTH PLAINS WITH AFTERNOON GUST
POTENTIAL STRUGGLING TO REACH 30 MPH. 06Z BIAS-CORRECTED MAV
GUIDANCE DID NOT EXECUTE PROPERLY...THOUGH INFERENCE SUGGESTS
SUSTAINED WINDS ONLY AROUND 20 MPH FOR MOST AREAS WELL SOUTH OF
HIGHWAY 70. NORTH OF THIS LINE WE ARE ALREADY SEEING STRONGER
GRADIENT WINDS AND DEEPER MIXING/HIGHER GUSTS...SO THE FORECAST
FOR THESE AREAS REMAINS ON TRACK. NO OTHER UPDATES AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 524 AM CST SAT NOV 12 2011/
AVIATION...
WINDS WILL BECOME BREEZY BEGINNING LATE THIS MORNING THROUGH LATE THIS
AFTERNOON AT BOTH TAF SITES IN RESPONSE TO A STRENGTHENING SURFACE
PRESSURE GRADIENT. MID AND HIGH LEVEL CLOUDS WILL CONTINUE TO BE
THICK AS WELL. KLBB MAY SEE MINOR VISIBILITY RESTRICTIONS DUE TO
BLDU BUT HAVE NOT INCLUDED ANY MENTION IN THE TAF AT THE MOMENT.
SOUTHWESTERLY WINDS WILL REMAIN BREEZY TONIGHT.
PREV DISCUSSION... /ISSUED 417 AM CST SAT NOV 12 2011/
SHORT TERM...
EPIC ALASKA STORM SYSTEM WILL MOVE ACROSS THE INTERMOUNTAIN REGION
TODAY BRINGING WINDY CONDITIONS FOR WEST TEXAS. HOWEVER...NOT AS
WINDY AS SEEN IN WESTERN ALASKA. THE HEIGHT GRADIENT WILL TIGHTEN UP
IN RESPONSE TO THIS SYSTEM. A SURFACE TROUGH WILL BISECT THE AREA
WITH THE CENTER OF A SURFACE LOW IN THE NORTHERN PLAINS. WIDESPREAD
SUBSIDENCE WILL ENCOMPASS THE REGION THIS AFTERNOON ALTHOUGH MIXING
HEIGHTS WILL NOT BE TOO IMPRESSIVE. MODEL SOUNDINGS SHOW THE
ATMOSPHERE MIXING TO AROUND 800 TO 750 MB. THE MID AND HIGH CLOUDS
STILL ACROSS THE REGION WILL LIKELY KEEP THIS MIXING LIMITED. CLOUDS
WILL BEGIN TO THIN OUT LATE THIS MORNING. MID LEVEL WINDS ARE NOT
TOO IMPRESSIVE EITHER WITH A 700MB WIND MAX EXTENDING FROM NORTHEAST
NEW MEXICO INTO THE WESTERN TEXAS PANHANDLE. THESE DOWNSLOPING WIND
WILL SEND TEMPERATURES SOARING INTO THE 70S FOR MOST AREAS WITH
LOWER 80S IN THE SOUTHEASTERN TEXAS PANHANDLE. MODELS HAVE BEEN OVER
FORECASTING THE SURFACE DEW POINTS THE PAST SEVERAL DAYS AND WILL
CONTINUE TO UNDERCUT THE DEW POINT GUIDANCE BECAUSE OF THIS. THE
PRESSURE GRADIENT WILL REMAIN STRONG OVERNIGHT WITH A WESTERLY LOW
LEVEL JET OF 30 TO 40KT KEEPING WINDS AND TEMPERATURES UP TONIGHT.
JDV
LONG TERM...
MODEST HEIGHT AND PRESSURE GRADIENTS WILL REMAIN SUNDAY FOLLOWING
PASSAGE OF WEAKENING UPPER LOW TO OUR NORTHEAST. THIS SHOULD RESULT
IN A BREEZY DAY SUNDAY WITH HIGH CLOUDS LIMITING CONFIDENCE OF
MIXING DEPTH WHICH THUS IMPACTS BOTH HIGH TEMPERATURES AND WIND
SPEEDS. UPPER LOW PRESSURE APPROACHING FROM NORTHWEST MEXICO NOW
SHOWING MUCH CLOSER MODEL SPREAD WITH MAJORITY OF FEATURES THOUGH
THE PREVIOUSLY LAGGING GFS NOW HAS BECOME THE PACE SETTER...AND SO
WE REMAIN LESS INCLINED TOWARDS ITS SOLUTION. PREFER INSTEAD A
BLEND BETWEEN MORE CONSISTENT WRF/NAM AND ECMWF WITH A SOMEWHAT
SLOWER APPROACH AND OPENING OF THE LOW...RETAINING LOW/LIMITED
SHOWER CHANCES MONDAY FAVORING STILL SOUTHEASTERN SECTIONS. WEAK
FRONT WILL FOLLOW TUESDAY THOUGH ECMWF OFFERS MORE SUBSTANTIAL
SURFACE RIDGING CENTERED ON MID-WEEK WITH AT LEAST A BLENDED
SOLUTION JUSTIFIED. WE LOWERED TEMPERATURES A CATEGORY OR SO FOR
MID WEEK. IN EITHER CASE...A DRY OUTLOOK WITH MODEST LATE PERIOD
WARMING APPEARS IN THE OFFING AS BROAD LOW AMPLITUDE UPPER LEVEL
CYCLONIC FLOW OVER MID-CONTINENT EVOLVES TOWARDS SIMILAR LOW
AMPLITUDE ANTICYCLONIC CURVATURE LATER IN THE WEEK. RMCQUEEN
FIRE WEATHER...
ELEVATED AND CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED THIS
AFTERNOON. LATEST RFTI-MOD VALUES INDICATE LOW TO HIGH CRITICAL
VALUES MOSTLY FOR AREAS ON THE CAPROCK. STRONG WESTERLY WINDS WILL
DEVELOP THIS AFTERNOON IN RESPONSE TO A STRENGTHENING SURFACE
PRESSURE GRADIENT. THE HIGHEST WINDS ARE EXPECTED TO BE ACROSS THE
SOUTHWESTERN TEXAS PANHANDLE. THESE STRONG WINDS WILL ALSO CAUSE
TEMPERATURES TO BE AROUND 10 DEGREES ABOVE NORMAL. THE WARM
TEMPERATURES COMBINED WITH THE VERY DRY SURFACE AIR WILL CAUSE
AFTERNOON RELATIVE HUMIDITY VALUES TO DROP BELOW CRITICAL VALUES.
ENOUGH MID AND LOW LEVEL HEIGHT AND PRESSURE GRADIENTS SHOULD
REMAIN SUNDAY FOR A BREEZY DAY FAVORING NORTHWESTERN COUNTIES WITH
ELEVATED FIRE DANGER THREAT. HOWEVER MID LEVEL MOISTURE IS
EXPECTED TO MIX TO LOWER LEVELS AND MAY HOLD DEWPOINTS UP ENOUGH
TO LIMIT ABILITY OF RELATIVE HUMIDITY LEVELS TO DROP. RMCQUEEN
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 71 42 69 42 64 / 0 0 0 10 10
TULIA 73 43 71 45 65 / 0 0 0 10 20
PLAINVIEW 74 44 72 46 65 / 0 0 0 10 20
LEVELLAND 74 45 72 47 66 / 0 0 0 10 20
LUBBOCK 75 46 73 48 66 / 0 0 0 10 20
DENVER CITY 73 46 72 47 67 / 0 0 10 10 20
BROWNFIELD 75 46 73 48 67 / 0 0 0 10 20
CHILDRESS 80 49 77 50 68 / 0 0 0 10 20
SPUR 79 47 77 50 70 / 0 0 0 10 20
ASPERMONT 79 50 78 52 72 / 0 0 0 10 30
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 5 PM CST THIS AFTERNOON FOR THE FOLLOWING
ZONES: TXZ021>025-027>031-033>036.
&&
$$
93/20
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
308 PM CST SAT NOV 12 2011
.VERY SHORT TERM...TONIGHT AND SUNDAY.
HIGH CLOUDS WILL CONTINUE TO SHIFT INTO THE AREA THIS
EVENING...WITHIN WARM AIR ADVECTION REGIME. SOUTH WINDS SHOULD
REMAIN UP TONIGHT WITH TIGHT PRESSURE GRADIENT REMAINING. INCREASING
MOISTURE WITH WARM AIR ADVECTION IN THE LOWEST LEVELS WILL SATURATE
AIR COLUMN UNDER INVERSION...AND SHOULD LEAD TO LOW STRATUS CLOUD
DEVELOPMENT LATER TONIGHT. NAM/GFS/RUC FORECAST SOUNDINGS ALL SHOW
THIS DEVELOPMENT...WITH THE RUC TOO AGGRESSIVE WITH ITS ONSET. THIS
SHOULD KEEP LOWS IN THE LOWER TO MID 40S.
LOW STRATUS CLOUDS SHOULD LINGER THROUGH THE MORNING SUNDAY...AS
MOIST AIR REMAINS TRAPPED UNDER INVERSION. THESE CLOUDS SHOULD LIMIT
SOME OF THE GUSTINESS WITH THE WINDS DURING THE MORNING...UNTIL THE
COLD FRONT PASSES THROUGH THE AREA LATE MORNING/EARLY AFTERNOON.
PRESSURE GRADIENT ACTUALLY WEAKENS WITH APPROACH AND PASSING OF THE
FRONT DURING THIS TIME...WHICH SHOULD ALSO LIMIT SOME OF THE MIXING
AND GUSTS. SHORTWAVE TROUGH ALSO SHIFTS THROUGH THE REGION DURING
THIS TIME. THIS AND THE FRONT SHOULD ALLOW FOR CHANCES OF
SHOWERS...THOUGH AIR COLUMN HAS A HARD TIME SATURATING THROUGH A
DEEP LAYER. SHOWER CHANCES LINGER IN THE NORTHEAST INTO THE EARLY
AFTERNOON.
BEST SHOT AT STRONG WINDS APPEARS TO BE AFTER THE COLD FRONTAL
PASSAGE DURING THE AFTERNOON...ESPECIALLY IN THE FAR SOUTHEAST
COUNTIES WHERE THE PRESSURE GRADIENT WILL BE THE STRONGEST. DRY SLOT
STAYS JUST SOUTH OF THE FORECAST AREA AS WELL DURING THE AFTERNOON.
FOR NOW...WILL HOLD OFF ON A WIND ADVISORY FOR THE FAR SOUTHEAST
COUNTIES. A LOT WILL DEPEND ON HOW EXTENSIVE THE LOW STRATUS
BECOMES. HIGHS SHOULD BE IN THE LOWER TO MID 50S.
.SHORT TERM...SUNDAY NIGHT THROUGH TUESDAY.
FOCUS OF THIS PERIOD ON LIGHT PRECIP THREAT ON MONDAY AND TUESDAY.
PASSING SHORT WAVE TROUGH ON SUNDAY WILL NUDGE BAROCLINIC ZONE
SOUTHWARD INTO CENTRAL MS VALLEY REGION WHICH WILL EXTEND NORTHEAST
INTO ERN GTLAKES. SHORT TERM GUIDANCE IN GOOD AGREEMENT ON CARRYING
SHORT WAVE ALONG THERMAL RIBBON ENE ON MONDAY. BOTH GFS AND NAM
KEEP QPF SOUTH OF WI OVER IL/IN INTO SRN LWR MI ON MONDAY...HOWEVER
OTHER GUIDANCE INCLUDING ECMWF...UKMT AND GEM-NHEM DOES BRING LIGHT
QPF INTO SRN WI. FURTHER DIAGNOSIS OF NAM AND GFS REVEALS BURST OF
10 TO 20 UNIT LAYER Q-VECTOR CONVERGENCE MOVING RAPIDLY EWD ACROSS
SRN WI WITH LAYER RH EXTENDING FROM 1K FEET THROUGH 10K. 295 THETA
SFC MONDAY MORNING SHOWS RAPID MOISTENING WITH CONDENSATION PRESSURE
DEFICITS LOWERING TO LESS THAN 10MB WITH 3-5MICROBARS ISENTROPIC
UPGLIDE. OMEGA QUICKLY SHIFTS EAST IN THE AFTN. WL CONTINUE LOW
POPS FOR NOW...WITH BEST CHANCE IN THE SOUTHEAST CORNER OF WI.
LOW PRESSURE MOVING EAST THRU SRN CAN WL DRAG MID LEVEL TROF AND SFC
FRONT THROUGH SRN WI ON TUE. MOISTURE AND SATURATION LIMITED AND
CONFINED MOSTLY TO NRN HALF OF WI. FOR NOW WL CONTINUE SCHC POPS ON
TUE...WITH COLDER AIR SURGING IN DURING THE DAY BEHIND SFC FRONT. WL
HAVE NARROW STRIP OF SLIGHTLY HIGHER POPS ALONG NRN BORDER.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY.
GENERAL MODEL CONSENSUS THROUGH THIS PERIOD...FOR THE MOMENT.
DESPITE LIMITED FORCING ASSOCIATED WITH TUESDAY SHORT WAVE...PUSH OF
COLDER AIR WILL SETTLE OVER SOUTHERN WI TUE NIGHT AND WED. 85H
TEMPS EXPCD TO DROP AROUND 15C IN THE 24 HOUR PERIOD FROM MID-DAY
TUE TO WED...TO AROUND -10C. HENCE DAYTIME TEMPS WILL BE IN THE 30S
FOR MOST OF WED.
AMPLIFYING LONG WAVE TROFFING STILL EXPECTED TO DEVELOP UPSTREAM
OVER NORTHWEST CONUS AND SW CANADA LATER NEXT WEEK. INITIAL PIECE OF
ENERGY EJECTED FROM THE LONG WAVE TROUGH EXPCD TO PUSH INTO THE NRN
PLAINS AND SRN CANADA ON THU AND FRI. THIS WILL RESULT IN SHIFTING
LOW LEVEL WINDS TO THE SOUTHWEST WHICH WILL USHER WARMER AIR BACK
INTO SRN WI ON THU AND FRI. STRONGER SHORT WAVE EJECTED EASTWARD
ACROSS THE ROCKIES INTO THE PLAINS ON SATURDAY WILL FURTHER INCREASE
THE SOUTH WINDS WHICH SHOULD PULL DEEPER MOISTURE GRADUALLY
NORTHWARD. BY SAT...SRN WI WL LIE WITHIN THERMAL RIBBON AND HAVE A
BETTER CHANCE FOR ISENTROPIC UPGLIDE AND SATURATION LEADING TO
INCREASING PRECIP CHANCES. GFS 5 DAY 500H MEANS INDICATING LARGE
DIPOLAR PATTERN SETTING UP OVER CONUS BY 00Z/20. LARGE POSITIVE
HEIGHT ANOMOLY OVER 150 METERS OVER ERN CONUS OFFSET BY NEGATIVE
ANOMOLY OVER 200 METERS UPSTREAM OVER WRN CONUS. THIS REINFORCES
FACT FOR MORE WIDESPREAD PRECIP FOR NEXT WEEKEND.
&&
.AVIATION /00Z TAFS/...GUSTY SOUTH TO SOUTHWEST WINDS ARE EXPECTED
THROUGH LATE AFTERNOON AT TAF SITES...WITH INCREASING HIGH CLOUDS.
THE GUSTS WILL SUBSIDE BY SUNSET...BUT SUSTAINED SOUTH WINDS WILL
REMAIN AROUND 10 TO 13 KNOTS THROUGH TONIGHT. LOW LEVEL WIND SHEAR
IS EXPECTED TONIGHT WITH LOW LEVEL JET CLIPPING THE AREA. 2000 FOOT
LEVEL SOUTHWEST WINDS OF 45 TO 50 KNOTS ARE EXPECTED THROUGH THE
NIGHT INTO EARLY SUNDAY.
IFR CEILINGS ARE EXPECTED TO DEVELOP LATER TONIGHT WITH INCREASING
MOISTURE AND MILDER AIRMASS...AROUND 09Z SATURDAY. THESE CLOUDS
SHOULD CONTINUE UNTIL COLD FRONT PUSHES THROUGH THE AREA...MADISON
BY 19Z SUNDAY AND EASTERN SITES BY 20Z TO 21Z SUNDAY. MVFR
VISIBILITIES ALSO POSSIBLE...BUT LOWER CONFIDENCE WITH BREEZY
CONDITIONS SO LEFT OUT OF TAFS.
WINDS MAY WEAKEN FOR A TIME WITH APPROACH AND PASSING OF FRONT
SUNDAY. SCATTERED RAIN SHOWERS ALSO POSSIBLE WITH FRONT AND PASSING
UPPER LEVEL DISTURBANCE. FOR NOW...WILL JUST MENTION VICINITY
SHOWERS IN TAFS DURING THE LATE MORNING AND EARLY AFTERNOON.
SOUTHWEST WINDS SHOULD INCREASE QUICKLY IN THE WAKE OF THE FRONT BY
MID AFTERNOON...WITH GUSTS IN THE 30 TO 35 KNOT RANGE. EASTERN TAF
SITES HAVE BEST SHOT AT HIGHER END GUSTS. VFR CEILINGS ALSO EXPECTED
TO RETURN BEHIND THE FRONT.
&&
.MARINE...SMALL CRAFT ADVISORY IN EFFECT UNTIL 15Z SUNDAY. PRESSURE
GRADIENT REMAINS TIGHT TONIGHT THROUGH SUNDAY NIGHT ACROSS THE
NEARSHORE WATERS. SOUTH/SOUTHWEST WINDS OF 15 TO 25 KNOTS ARE
EXPECTED.
STRONG LOW LEVEL JET PASSING JUST SOUTHEAST OF THE AREA ON SUNDAY
SHOULD BRING FREQUENT 35 TO 40 KNOT SOUTH/SOUTHWEST GALES TO THE
NEARSHORE WATERS. LOW CLOUDS AND BAGGY PRESSURE GRADIENT MAY LIMIT
GUSTS FROM TIME TO TIME DURING THE LATE MORNING. SOUTHWEST GALES
EXPECTED AFTER THE COLD FRONTAL PASSAGE DURING THE AFTERNOON.
THUS...WILL GO WITH A GALE WARNING FROM 15Z SUNDAY TO 00Z
MONDAY...REPLACING THE GALE WATCH. THESE WINDS WILL GENERATE HIGH
WAVES UP TO 6 TO 10 FEET BY SUNDAY...HIGHEST TOWARD THE OPEN WATERS.
BRISK WINDS AND HIGH WAVES SHOULD SLOWLY SUBSIDE SUNDAY NIGHT INTO
MONDAY...AS PRESSURE GRADIENT SLOWLY WEAKENS. A SMALL CRAFT ADVISORY
WILL EVENTUALLY BE NEEDED FOR SUNDAY NIGHT...PERHAPS INTO MONDAY.
BRISK WINDS AND HIGH WAVES ARE POSSIBLE AGAIN TUESDAY INTO TUESDAY
NIGHT...AS A COLD FRONT APPROACHES AND MOVES THROUGH THE REGION.
HIGHEST WAVES WOULD BE TOWARD THE OPEN WATERS.
&&
CONFIDENCE...
TONIGHT AND SUNDAY...MEDIUM.
SUNDAY NIGHT THROUGH TUESDAY...MEDIUM.
TUESDAY NIGHT THROUGH THURSDAY...MEDIUM.
FRIDAY AND SATURDAY...LOW TO MEDIUM.
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 15Z/13 FOR LMZ643>646.
GALE WARNING 15Z/13 TO 00Z/14 FOR LMZ643>646.
&&
$$
SHORT TERM/LONG TERM...MBK
VERY SHORT TERM/AVIATION/MARINE...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
200 AM CST SAT NOV 12 2011
.SHORT TERM...TODAY THROUGH MONDAY NIGHT
200 AM CST SAT NOV 12 2011
FORECAST CONCERNS FOCUS ON THE NEXT SHORTWAVE TROUGH TO IMPACT THE
AREA...PCPN CHANCES AND WINDS.
STRONG SHORTWAVE TROUGH INDICATED VIA THE LATEST WATERVAPOR
IMAGERY...CHURNING ACROSS THE PAC NW. THIS FEATURE WILL MOVE QUICKLY
EASTWARD...ACROSS THE PLAINS TONIGHT...MOVING ACROSS THE FORECAST
AREA BETWEEN 12-18Z SUN...THEN EXITING INTO CANADA BY SUN NIGHT. AT
THE SFC THE ASSOCIATED COLD FRONT WILL SLIP JUST AHEAD OF THE UPPER
LEVEL WAVE...WITH STRONG LOW LEVEL /925-850 MB/ WARM AIR ADVECTION
AND ISENTROPIC UPGLIDE /285-300 K/ OUT AHEAD OF THE FRONT. THESE
THERMODYNAMICS WOULD IMPACT THE REGION FROM 06-12Z SUN. DECENT
SLOPING FRONTOGENETIC RESPONSE AROUND THE FRONT AND BEHIND IT SUN
MORNING. SATURATION REMAINS A LIMITING FACTOR TO THIS SYSTEM/S PCPN
CHANCES THOUGH.
BUFKIT SOUNDINGS AND WEST-EAST RUNNING X-SECTIONS POINT TO ONLY A
VERY LOW SATURATION...SFC TO MAYBE 1500 FT...OVERNIGHT TONIGHT. THE
DEEPER SATURATION IS MORE ALONG AND JUST POST THE
FRONT...HIGHLIGHTED LOCALLY IN THE 12-18Z TIME FRAME. IF THE
SATURATION WAS JUST A BIT DEEPER...THE THERMODYNAMICS THROUGH THE
MOISTURE WOULD LIKELY LEAD TO AREAS OF DRIZZLE. STILL FEEL ITS
PROBABLY TOO SHALLOW THOUGH...SO WILL KEEP IT DRY WITH RESPECT TO
DRIZZLE TONIGHT.
THE MODELS HAVE BEEN CONSISTENT WITH STEAMING THE SHORTWAVE THROUGH
SUNDAY MORNING...AND WITH THE DEEPER SATURATION AND FRONTOGENETIC
LIFT...THIS WOULD BE THE TIME PERIOD FOR THE BEST RAIN CHANCES.
AMOUNTS DON/T LOOK ALL THAT MUCH...1/10 TO MAYBE 2/10 OF AN INCH.
BEST CHANCES CONTINUE TO LIE ACROSS THE NORTHERN 2/3 OF THE
FORECAST AREA.
ATTENTION NOW TURNS TO WINDS AS THE PRESSURE GRADIENT WILL TIGHTEN
AHEAD OF THE APPROACHING SHORTWAVE TROUGH. WINDS DON/T BECOME
UNIDIRECTIONAL IN THE VERTICAL UNTIL LATE SUN MORNING...WHICH WOULD
PROMOTE BETTER MIXING AND GREATER GUSTS. HOWEVER...WE WILL LIKELY BE
UNDER A GOOD AMOUNT OF CLOUDS STILL...WHICH WILL HELP INHIBIT SOME
OF THAT POTENTIAL MIXING. SUNDAY STILL LOOKS TO BE A FAIRLY
WINDY/BREEZY DAY...MORE SO THAN TODAY...ALTHOUGH GUSTS MAYBE A BIT
SUBDUED COMPARED TO WHAT THEY COULD BE ON ACCOUNT OF CLOUDS. DON/T
FEEL WINDS WILL APPROACH ADVISORY CRITERIA AT THIS TIME.
.LONG TERM...TUESDAY THROUGH FRIDAY
200 AM CST SAT NOV 12 2011
DECENT AGREEMENT WITH A TUE SHORTWAVE PROGGED TO SWING ACROSS THE
UPPER MISSISSIPPI RIVER VALLEY VIA THE GFS/ECMWF SOLUTIONS. NOT
MUCH/IF ANY MOISTURE FEED AS THIS IS ABSORBED BY A FRONT/SERIES OF
UPPER AIR DISTURBANCES TO THE SOUTH. MODELS STILL DEPICT SOME LIGHT
QPF WITH THE TUES FEATURE...WITH BETTER CHANCES TO THE NORTH WHERE
THE SATURATION APPEARS DEEPER. A RIDGE OF HIGH PRESSURE THEN BUILDS
IN...BUT QUICKLY EXITS ON THU AS THE FLOW A LOFT IS FAIRLY
PROGRESSIVE. ANOTHER SHORTWAVE TROUGH THEN LOOKS TO SPIN EASTWARD
TOWARD THE REGION. SFC WARM FRONT/LOW LEVEL WARM AIR ADVECTION WOULD
LIFT NORTHWARD INTO THE AREA AHEAD OF THE FEATURE...BRINGING THE
POTENTIAL FOR SOME PCPN. MODELS DIFFER HERE WITH A MUCH QUICKER
SOLUTION VIA THE EC. MODELS HAVING A DIFFICULT TIME WITH THIS
WEATHER SYSTEM...ESPECIALLY THE EC WHICH HAS SHOWN A VARIETY OF
SOLUTIONS OVER ITS PAST FEW RUNS. THE GFS HAS STAYED ON THE SLOWER
SIDE...ALTHOUGH IT TOO HAS SOME CONTINUITY ISSUES. WILL HOLD WITH
THE CONSENSUS SOLUTION FOR THE FORECAST DETAILS FOR THE END OF THE
WORK WEEK AS A RESULT.
&&
.AVIATION...THROUGH 06Z SUNDAY
1105 PM CST FRI NOV 11 2011
THE MAIN NEAR TERM QUESTION IS WITH WHETHER ANY VISIBILITY
REDUCTIONS WILL OCCUR DUE TO A COMBINATION OF CLEAR SKIES...A
SHARP LOW LEVEL INVERSION AND LEFT OVER MOISTURE FROM MELTING
SNOW. VISIBILITY HAS YET TO DROP AT ANY SITES ACROSS THE
REGION...LIKELY DUE TO THE WINDS THAT HAVE BEEN UP BETWEEN
6-10KTS. THE LATEST FEW RUNS OF THE RUC HAVE BEEN SHOWING THAT
ANY RESTRICTIONS APPEAR LESS LIKELY AT RST AND LSE...PARTICULARLY
AT RST WHERE DEW POINT DEPRESSIONS REMAIN AT 2C THROUGH THE
MORNING. GIVEN THAT THE WINDS STAY UP...IT APPEARS THAT ANY DROPS
IN VISIBILITY AT LSE WOULD REMAIN ABOVE 6SM...SO WILL NOT BE
INCLUDING ANY MVFR DROPS AT THIS TIME.
HOW STRONG THE WINDS WILL GUST ON SATURDAY WILL BE THE NEXT
QUESTION WITH THE TIGHT PRESSURE GRADIENT STILL IN PLACE. GUSTS IN
THE 18 TO 24KT RANGE STILL LOOK REASONABLE FOR LATE IN THE MORNING
AND EARLY AFTERNOON OUT OF THE SOUTH AS THE NEXT STORM SYSTEM
MOVES INTO THE NORTHERN PLAINS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
200 AM CST SAT NOV 12 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM... RIECK
LONG TERM.... RIECK
AVIATION..... HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1105 PM CST FRI NOV 11 2011
.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
219 PM CST FRI NOV 11 2011
AT 3 PM...A LOW PRESSURE SYSTEM WAS MOVING EAST THROUGH WESTERN
ONTARIO. TO THE SOUTH OF THIS SYSTEM...A WARM FRONT WAS STARTING
TO WORK ITS WAY EAST INTO THE FORECAST AREA. THIS WARMING IS BEING
AIDED BY DOWN SLOPE OFF OF THE NORTHERN AND CENTRAL PLAINS. IN
ADDITION...THE AIR MASS IS MORE OF PACIFIC ORIGIN THAN CONTINENTAL
POLAR.
FOR LATE THIS AFTERNOON AND TONIGHT...THE MOS AND MANY OF THE
OTHER MODELS DEW POINTS WERE JUST TOO MOIST. THE ONLY DATA SET
THAT SEEMED REALISTIC WAS THE ADJUSTED MAV...SO THIS WAS USED TO
POPULATE THE GRIDDED DATA BASE.
FROM LATE SATURDAY NIGHT INTO SUNDAY MORNING...THE 11.12Z MODELS ARE
IN VERY GOOD AGREEMENT THAT A LOW PRESSURE SYSTEM /CURRENTLY
MOVING INTO WASHINGTON STATE/ WILL BE MOVING EAST THROUGH THE
REGION. THIS SYSTEM IS ACTUALLY REMNANTS OF THE VERY STRONG STORM
THAT MOVED THROUGH THE GULF OF ALASKA ON THURSDAY. AHEAD OF THIS
SYSTEM...THERE WILL SOME WARM AIR ADVECTION. HOWEVER THE MODEL
SOUNDINGS SUGGEST THAT MUCH OF THIS WARMING WILL ACTUALLY HELP
STEEPEN THE INVERSION ALOFT. CONS RAW HOURLY TEMPERATURE DATA
SUGGEST THAT THE TEMPERATURES WILL EITHER STABILIZE OR MAYBE RISE
A COUPLE OF DEGREES AROUND SUNRISE SUNDAY...AND THEN FALL THROUGH
THE REMAINDER OF THE MORNING AS STRONG COLD AIR ADVECTION MOVES
INTO THE REGION. THIS SEEMED REALISTIC...SO IT WAS USED TO
POPULATE THE HOURLY TEMPERATURES FOR THIS TIME PERIOD.
WHILE THERE IS NOT TREMENDOUS MOISTURE /HOWEVER IT DOES NOT TAKE
MUCH TO GENERATE PRECIPITATION THIS TIME OF YEAR/ AHEAD OF THIS
WAVE...THERE LOOKS TO MORE THAN SUFFICIENT SYNOPTIC AND ISENTROPIC
LIFT TO GENERATE SOME SHOWERS. SINCE THE BEST LIFT AND MOISTURE
WILL BE ALONG THE FRONT...TEMPERATURES ALOFT SHOULD REMAIN WARM
ENOUGH FOR THE PRECIPITATION TO REMAIN IN THE FORM OF RAIN. SINCE
THIS WAS A VERY CONSISTENT SIGNAL IN THE MODELS...PRECIPITATION
CHANCES WERE RAISED A BIT MORE.
FROM LATE SUNDAY MORNING INTO THE AFTERNOON...THE MODEL SOUNDINGS
SHOW THAT THE 1000-800 MB LAPSE RATES WILL BE GREATER 8C/KM. IN
ADDITION...THERE WILL BE STRONG SUBSIDENCE BELOW 10K FEET. THIS
WILL RESULT IN THE STRONGER WINDS FROM ALOFT MIXING DOWN TO THE
SURFACE. SUSTAINED WINDS WILL BE IN THE 20 TO 30 MPH RANGE AND
WIND GUSTS WILL BE AROUND 40 MPH. THIS PERIOD WILL HAVE TO WATCHED
FOR A POTENTIAL WIND ADVISORY.
.LONG TERM...MONDAY THROUGH FRIDAY
219 PM CST FRI NOV 11 2011
WHILE THE 11.12Z MODELS ARE IN GOOD AGREEMENT THAT A SHORT WAVE
TROUGH WILL BE MOVING EAST THROUGH THE FORECAST AREA LATE MONDAY
NIGHT THROUGH TUESDAY...THERE ARE STILL TIMING AND LOCATION
DIFFERENCES. THIS CREATES ISSUES AS FAR AS WHAT TIME PERIOD TO
PLACE THE PRECIPITATION IN AND ALSO ITS TYPE. DUE TO THIS...JUST
BROAD BRUSHED A SMALL /15 TO 24 PERCENT/ CHANCE OF PRECIPITATION
ACROSS THE AREA FOR TUESDAY. ALSO SEEING MIXED SIGNALS FOR
PRECIPITATION TYPES...SO JUST WENT WITH RAIN AND SNOW SHOWERS IN
THE MORNING...AND RAIN SHOWERS IN THE AFTERNOON.
FROM WEDNESDAY INTO WEDNESDAY NIGHT...THERE LOOKS LIKE THAT
ANOTHER WEAK WAVE WILL MOVE THROUGH THE REGION ALONG THE
BAROCLINIC ZONE. THE GFS PRODUCES A BAND OF LIGHT PRECIPITATION ACROSS
NORTHERN IOWA...SOUTHERN WISCONSIN...AND NORTHERN ILLINOIS.
MEANWHILE THE GEM PRODUCES A BAND OF PRECIPITATION ACROSS NORTHERN
MINNESOTA AND NORTHERN WISCONSIN. THIS HAS BEEN SUCH AN
INCONSISTENT SIGNAL THAT THE FORECAST WAS LEFT DRY.
ON THURSDAY AND THURSDAY NIGHT...THE ECMWF GENERATES PRECIPITATION
ACROSS THE ENTIRE AREA AS A LOW PRESSURE SYSTEM MOVES EAST THROUGH
THE REGION. THIS IS A BIT FASTER THAN THE PREVIOUS RUN. SINCE
THERE WERE TIMING DIFFERENCES AND THE GFS WAS DRY FOR THIS TIME
PERIOD...NO CHANGES WERE MADE TO THE DRY FORECAST FOR THIS TIME PERIOD.
ON FRIDAY AND FRIDAY NIGHT...BOTH THE GFS AND ECMWF MOVE A LOW
PRESSURE SYSTEM EAST THROUGH THE REGION. IT IS ACTUALLY THE SAME
SYSTEM THAT THE ECMWF MOVES THROUGH THE REGION A DAY EARLIER...BUT
THE SYSTEM STILL LINGERS ACROSS THE AREA SO IT STILL GENERATES
SOME SMALL PRECIPITATION CHANCES ACROSS THE EAST AND SOUTH DURING
THIS TIME PERIOD. MEANWHILE WITH THE GFS IS APPROXIMATELY 36 HOURS
SLOWER AND THE COLD FRONT DOES NOT MOVE THROUGH THE AREA UNTIL
FRIDAY NIGHT. WHILE THERE CONTINUES TO BEING TIMING ISSUES WITH
THIS SYSTEM...THERE WAS ENOUGH OF A CONSISTENT SIGNAL FOR A SMALL
CHANCE OF PRECIPITATION TO BE ADDED TO THE FORECAST GRID.
&&
.AVIATION...THROUGH 06Z SUNDAY
1105 PM CST FRI NOV 11 2011
THE MAIN NEAR TERM QUESTION IS WITH WHETHER ANY VISIBILITY
REDUCTIONS WILL OCCUR DUE TO A COMBINATION OF CLEAR SKIES...A
SHARP LOW LEVEL INVERSION AND LEFT OVER MOISTURE FROM MELTING
SNOW. VISIBILITY HAS YET TO DROP AT ANY SITES ACROSS THE
REGION...LIKELY DUE TO THE WINDS THAT HAVE BEEN UP BETWEEN
6-10KTS. THE LATEST FEW RUNS OF THE RUC HAVE BEEN SHOWING THAT
ANY RESTRICTIONS APPEAR LESS LIKELY AT RST AND LSE...PARTICULARLY
AT RST WHERE DEW POINT DEPRESSIONS REMAIN AT 2C THROUGH THE
MORNING. GIVEN THAT THE WINDS STAY UP...IT APPEARS THAT ANY DROPS
IN VISIBILITY AT LSE WOULD REMAIN ABOVE 6SM...SO WILL NOT BE
INCLUDING ANY MVFR DROPS AT THIS TIME.
HOW STRONG THE WINDS WILL GUST ON SATURDAY WILL BE THE NEXT
QUESTION WITH THE TIGHT PRESSURE GRADIENT STILL IN PLACE. GUSTS IN
THE 18 TO 24KT RANGE STILL LOOK REASONABLE FOR LATE IN THE MORNING
AND EARLY AFTERNOON OUT OF THE SOUTH AS THE NEXT STORM SYSTEM
MOVES INTO THE NORTHERN PLAINS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
219 PM CST FRI NOV 11 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...HALBACH
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
851 PM CST FRI NOV 11 2011
.UPDATE...
WILL BE WATCHING TEMPERATURES OVER THE SNOW PACK CAREFULLY AS
MIXING HAS HELD TEMPERATURES UP A LITTLE MORE THIS EVENING...WITH
LONE ROCK THE EXCEPTION AS WINDS IN THE WI RIVER VALLEY HAVE
CALMED. DEW POINTS ALSO TRYING TO RISE...THOUGH LOWER DEW POINTS
IN WESTERN LOCATIONS ON MSAS ANALYSIS FIT FAIRLY WELL WITH DEEPER
SNOW COVER. STILL FEEL RUC BUFKIT SOUNDINGS ARE OVER-DOING DEW
POINTS IN THE WEST AND CURRENT FORECASTED LOWS WILL BE REACHED.
&&
.AVIATION/06Z TAFS/...
PROFILER NETWORK SHOW 925 MB WINDS INCREASING TO 20-30KTS OVER THE
REGION. WILL MONITOR FOR POSSIBILITY OF WIND SHEAR...ESPECIALLY
AT EASTERN TAF SITES...AS NAM INDICATES WINDS AROUND 1500 FT
COULD HIT 35-37 KTS FOR A TIME LATE THIS EVENING...THEN FALL OFF
AFTER 06Z TO 20 TO 25 KTS BEHIND TROUGH. SURFACE GRADIENT SHOULD
KEEP SURFACE WINDS UP ENOUGH TO KEEP DIFFERENTIAL BELOW CRITERIA
BUT WILL WATCH.
LATEST RUC/NAM BUFKIT SOUNDINGS ALSO SHOW MOISTURE TRAPPED UNDER
INVERSION IS VERY SHALLOW...AND FORECAST SURFACE DEW POINTS LOOK
A BIT TOO HIGH. THIS WILL PRODUCE FROST...WITH SOME SPOTTY GROUND
FOG AT WORST...VERSUS THE POTENTIAL FOR A STRATUS DECK FORMING
OVERNIGHT SHOWN IN EARLIER GUIDANCE. WILL KEEP AN EYE ON TRENDS
THE NEXT COUPLE OF HOURS...BUT EXPECT VFR CONDITIONS THROUGH
DAYBREAK AND THE REMAINDER OF THE FORECAST PERIOD.
&&
.MARINE UPDATE...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL
MIDNIGHT. WHILE WINDS HAVE EASED AT LAKE SHORE OB SITES...MID-LAKE
AND CHICAGO CRIB STILL GUSTING AT OR ABOVE CRITERIA. SURFACE
GRADIENT BEGINNING TO WEAKEN SO WINDS...CURRENTLY VEERING SOUTHWEST...
SHOULD WEAKEN THOUGH THE LATE EVENING. SUBSEQUENT WAVES AT OR NEAR
CRITERIA TOWARD THE OPEN WATER SHOULD SUBSIDE BY MIDNIGHT.
&&
.PREV DISCUSSION... /ISSUED 305 PM CST FRI NOV 11 2011/
VERY SHORT TERM...TONIGHT AND SATURDAY.
VORTICITY MAXIMUM AND ASSOCIATED CLOUDS EXITING THE AREA FROM WEST
TO EAST BY EVENING...SO CONTINUED CLEARING TREND. GUSTY SOUTH WINDS
SHOULD VEER SOUTHWEST AND WEAKEN SOMEWHAT WITH INVERSION BUILDING
THIS EVENING. STRONG INVERSION DEVELOPS NEAR THE GROUND...WITH WARM
AIR ADVECTION CONTINUING IN THE LOW LEVELS.
RUC/NAM FORECAST SOUNDINGS SHOWING SOME POTENTIAL FOR LOW STRATUS
DECK FORMING ACROSS THE AREA TONIGHT...IN RESPONSE TO THE STRONG
INVERSION AND MOIST NEAR SURFACE LAYER. HOWEVER...MODEL DEW POINTS
SEEM SOMEWHAT HIGH LATER TONIGHT INTO SATURDAY...AND NEAR SURFACE
WINDS SHOULD REMAIN HIGH ENOUGH TO KEEP THINGS MIXED. THUS...KEPT
SKIES CLEAR FOR TONIGHT INTO EARLY SATURDAY. LOWS IN THE UPPER 20S
FOR SNOW COVERED AREAS IN THE WEST...TO LOWER/MID 30S EAST...SEEM
REASONABLE WITH STRONG INVERSION AND 925MB TEMPERATURES OF 9 TO 11
DEGREES CELSIUS.
GUSTY SOUTH WINDS EXPECTED SATURDAY...AS PRESSURE GRADIENT TIGHTENS
AGAIN WITH DEEPENING LOW PRESSURE IN THE NORTHERN PLAINS. SUNNY
SKIES SHOULD ALLOW HIGHS TO CRACK THE MID 50S IN MOST AREAS. SNOW
AREAS MAY BE A BIT COOLER. SOME HIGH CLOUDS SHOULD WORK INTO THE
AREA LATER IN THE AFTERNOON.
SHORT TERM...SATURDAY NIGHT THROUGH MONDAY.
FOCUS OF THIS PERIOD ON SHORT WAVE TROUGH MOVING RAPIDLY WEST TO
EAST ACROSS WESTERN GREAT LAKES ON SUNDAY AND LINGERING BAROCLINIC
ZONE TO THE SOUTH. SHORT TERM GUIDANCE IN REASONABLE AGREEMENT ON
CARRYING VIGOROUS SHORT WAVE TROUGH ACROSS WI ON SUNDAY. STRONGEST
Q-VECTOR CONVERGENCE PASSES TO THE NORTH SUN MRNG. DESPITE
STRENGTHENING LOW LEVEL WINDS SATURDAY NIGHT AND SUNDAY...COLUMN
PWAT ONLY INCREASES AROUND ONE QUARTER INCH WITH MID LEVELS
REMAINING DRY SUN MRNG. DEEPER MOISTURE BOTTLED UP ALL THE WAY TO
THE GULF JUST HAS TOO FAR TO GO IN SHORT AMOUNT OF TIME. TO
ACKNOWLEDGE STRONG FORCING WL KEEP LOW CHANCE POPS GOING SUN MRNG
AND DIMINISH OR LOWER TO SCHC IN THE WEST IN THE AFTN. STRONGER
SUBSIDENCE AND DRYING SWEEP IN DURING THE AFTN. DRIER AIR MAY ERODE
CLOUDS FOR THE AFTN. 3 HOUR PRESS RISES ASSOCIATED WITH DEEPENING
LOW PRESSURE MAY REACH 3 TO 5 MB...HOWEVER NAM FARTHER SOUTH NEAR
TIP OF MN ARROWHEADWITH WITH SFC LOW AT 18Z/13 WITH RESULTANT
TIGHTER PRESSURE GRADIENT OVER SRN WI. GFS...ECMWF AND GEM FARTHER
NORTH INTO CANADA BY SEVERAL HUNDERED MILES WITH WEAKER GRADIENT.
850MB WINDS OF 40 TO 50 KTS AND POSSIBLE STRONG MIXING MAY RESULT IN
WINDS APPROACHING WIND ADVY CRITERIA LATER SUN MRNG AND AFTN.
WL KEEP A SMALL POP IN ON MONDAY FOR SOUTHEAST CWA DUE TO WEAK WAVE
MOVING EAST-NORTHEAST ALONG LINGERING BAROCLINIC ZONE EXTENDING FROM
CENTRAL MS VALLEY INTO ERN GTLAKES. BOTH NAM AND GFS KEEP MAIN
FORCING WITH THIS SYSTEM SOUTH OF WI...HOWEVER GFS HAS BEEN CREEPING
NORTHWARD WHILE ECMWF OVER THE LAST SEVERAL RUNS HAS BEEN EDGING
SOUTHWARD.
LONG TERM...MONDAY NIGHT THROUGH FRIDAY.
A SLIGHT INCREASE IN CONFIDENCE FOR THIS PERIOD FROM 24 HOURS
AGO...AS THE MAJORITY OF THE EXTENDED MODELS ARE COMING INTO BETTER
AGREEMENT. IN ADDITION...GFS ENSEMBLE MEMBERS AT BOTH 700H AND 500H
SHOWING BETTER AGREEMENT FROM TUE THROUGH THU. FAST WEST-NORTHWEST
FLOW EXPECTED THROUGH THIS PERIOD...WITH SRN WI REMAINING ON THE
NORTHERN FRINGE OF A TIGHT BAROCLINIC ZONE STRETCHING ACROSS THE
CENTRAL CONUS. ECMWF...GFS AND GEM IN GOOD AGREEMENT ON SOUTHERLY
EXTENSION OF SHORT WAVE TROUGH MOVING THROUGH SRN CANADA AFFECTING
WI ON TUE. BRIEF BURST OF MODERATE Q-VECTOR CONVERGENCE WITH THIS
FEATURE. MID-LEVEL MOISTURE LIMITED BUT ENOUGH FORCING AND
AGREEMENT TO WARRANT ADDING SMALL POPS FOR TUE.
FAST WESTERLIES KEEP DEEPER MOISTURE BOTTLED UP OVER THE SOUTHEAST
CONUS. HENCE FOR NOW EXPECTING DRY CONDITIONS FOR TUE NGT THROUGH
THU. LATER NEXT WEEK BOTH GFS AND LATEST ECMWF IN AGREEMENT ON
AMPLIFYING UPSTREAM TROFFING OVER PAC NW. INCREASING SOUTH WINDS
AHEAD OF THIS FEATURE WILL EVENTUALLY PULL MOISTURE NORTHWARD AND
INCREASE THE CHANCE FOR PRECIPITATION LATER FRI AND THE WEEKEND.
AVIATION /00Z TAFS/...VFR CONDITIONS EXPECTED THROUGH SATURDAY. DRY
AIRMASS TONIGHT SHOULD BRING CLEAR SKIES WITH LIGHT SOUTHWEST WINDS.
OUTSIDE SHOT OF LOW LEVEL WIND SHEAR EARLY TONIGHT...AND IFR
CEILINGS WITH LOW STRATUS LATER TONIGHT INTO EARLY SATURDAY.
LOW LEVEL JET TONIGHT INCREASES TO AROUND 30 KNOTS AT 2000 FEET
ABOVE GROUND LEVEL FROM AROUND 00Z TO 03Z SATURDAY. THIS WOULD BE
BORDERLINE POTENTIAL FOR LOW LEVEL WIND SHEAR...AND NOT CONFIDENT IN
ITS OCCURRENCE...SO LEFT OUT OF TAFS.
IFR CEILING DEVELOPMENT WOULD BE DUE TO THE COOL SURFACE UNDERNEATH
WARMING AIR AT A FEW THOUSAND FEET ABOVE GROUND LEVEL. NOT CONFIDENT
IN ITS OCCURRENCE WITH WINDS REMAINING UP ENOUGH...SO LEFT MENTION
OUT OF TAFS AS WELL. SOUTH WINDS BECOME GUSTY ONCE AGAIN SATURDAY
AFTERNOON...WITH GUSTS IN THE LOWER 20S KNOT RANGE POSSIBLE. SOME
HIGH CLOUDS SHOULD MOVE INTO TAF SITES TOWARD EVENING.
MARINE...SMALL CRAFT ADVISORY REMAINS IN EFFECT ONLY UNTIL
MIDNIGHT. GUSTY SOUTH WINDS TO 25 KNOTS WILL CONTINUE INTO EARLY
EVENING AS CLOUDS CLEAR OUT FROM WEST TO EAST...WITH TIGHT PRESSURE
GRADIENT. WINDS WILL VEER SOUTHWEST AND SHOULD WEAKEN SOMEWHAT
TONIGHT. SUBSEQUENT WAVES ARE EXPECTED TO REMAIN 3 TO 5 FEET TOWARD
THE OPEN WATERS INTO THIS EVENING...BEFORE SUBSIDING BY MIDNIGHT.
WAVES MAY SUBSIDE EVEN SOONER...SO EVENING SHIFT MAY END IT WITH THE
EVENING ISSUANCE OF THE NEARSHORE MARINE FORECAST.
ANOTHER SHOT AT SMALL CRAFT ADVISORY LEVEL WINDS AND WAVES EXISTS
FOR SATURDAY AFTERNOON THROUGH SATURDAY NIGHT...AS LOW PRESSURE AND
AN OCCLUDED FRONT MOVE THROUGH THE REGION. GUSTY SOUTH TO SOUTHWEST
WINDS TO 30 KNOTS ARE POSSIBLE AT TIMES.
SOUTHWEST GALES TO 40 KNOTS ARE POSSIBLE SUNDAY...WITH STRONG LOW
LEVEL WINDS AND GOOD MIXING CONDITIONS. HIGH WAVES OF AT LEAST 4 TO
8 FEET ARE ALSO POSSIBLE WITH THESE WINDS. CONFIDENT ENOUGH TO GO
WITH A GALE WATCH FROM 14Z SUNDAY TO 00Z MONDAY TO HIGHLIGHT THIS
POTENTIAL. WINDS AND WAVES WOULD THEN SLOWLY SUBSIDE SUNDAY NIGHT
INTO MONDAY.
CONFIDENCE...
TONIGHT AND SATURDAY...MEDIUM TO HIGH.
SATURDAY NIGHT...MEDIUM.
SUNDAY THROUGH MONDAY...LOW TO MEDIUM.
MONDAY NIGHT THROUGH THURSDAY...MEDIUM.
FRIDAY...LOW.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...GALE WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON FOR
LMZ643>646.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR LMZ643>646.
&&
$$
UPDATE...REM
TONIGHT/SATURDAY AND AVIATION/MARINE...WOOD
SATURDAY NIGHT THROUGH FRIDAY...MBK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1114 PM CST THU NOV 10 2011
.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
914 PM CST THU NOV 10 2011
MAIN FOCUS THIS EVENING HAS BEEN WITH WHETHER ANY LIGHT SNOW WOULD
HAVE TO BE ADDED TO THE FORECAST AFTER MIDNIGHT WITH THE NEXT
SYSTEM DROPPING THROUGH THE DAKOTAS. WITH ISENTROPIC LIFT ON THE
285K TO 290K SURFACE AND 850MB WARM AIR ADVECTION KICKING
IN...CLOUDS HAVE REFORMED ACROSS THE EASTERN DAKOTAS AND WESTERN
MINNESOTA. WHILE SOME RETURNS HAVE POPPED UP ACROSS THIS
REGION...THE LOW LEVEL REMAIN FAIRLY DRY PER 11.00Z ABR AND MPX
SOUNDINGS WITH NONE OF THE AUTOMATED SITES OUT THERE REPORTING
PRECIPITATION. 11.00Z NAM AND 11.01Z RUC SOUNDINGS FOR ACROSS THE
REGION SHOW THE RAPID MOISTENING ABOVE 800MB TONIGHT BUT A DRY
LAYER JUST BELOW THIS WITH DEW POINT DEPRESSIONS OF ABOUT 20C
AROUND 850MB. THUS...WHILE RADAR RETURNS WILL LIKELY BE SHOWING UP
TONIGHT ACROSS THE REGION...AM NOT EXPECTING ANY SNOW TO MAKE IT
DOWN TO THE GROUND. THE LONE EXCEPTION MAY BE ACROSS PARTS OF
NORTHERN WISCONSIN TOWARD DAYBREAK WHEN THE MID LEVEL SHORTWAVE
TROUGH AND PV ADVECTION DROPS DOWN BUT NOT EXPECTING MUCH IF ANY
ACCUMULATION.
HAVE ALSO TRENDED TOWARD A MORE CLOUDY SOLUTION OVERNIGHT WITH THE
MID LEVEL DECK HOLDING ON STRONG THROUGH MUCH OF WISCONSIN AND
HIGH LEVEL CLOUD COVER COMING IN AHEAD OF THE NEXT SYSTEM.
FROM PREVIOUS DISCUSSION...
FOR FRIDAY...CONTINUED ISENTROPIC LIFT IN THE MORNING/COUPLED WITH
WEAK 500-300MB PV-ADVECTION COULD BE ENOUGH TO FULLY SATURATE THE
COLUMN MAINLY ALONG/NORTH OF I-94. THERE IS STILL SOME QUESTION AS
TO HOW DRY THE SUB CLOUD LAYER WILL REMAIN...WITH THE NAM SHOWING
STRONGEST DEGREE OF SATURATION WHILE OTHER MODELS SHOW LESS. AS
SUCH...WILL INCLUDE A 20 POP FOR SNOW EARLY ON IN THE MORNING...
POSSIBLY MIXING/CHANGING TO RAIN LATER IN THE MORNING. BY FRIDAY
AFTERNOON...THE WARM FRONT/CLOUDS/PRECIPITATION CHANCES PUSH
EAST...LEAVING THE AREA IN THE SUNNY WARM SECTOR OF THE LOW WHICH
WILL BE OVER CENTRAL LAKE SUPERIOR. BREEZY SOUTHWEST WINDS DRAW IN
WARMER AIR...WITH THE 925-850MB TEMPERATURES INCREASING INTO THE 5
TO 8C RANGE BY LATE IN THE AFTERNOON WITH FULL SUNSHINE. THIS IS
EXPECTED TO YIELD HIGHS IN THE MIDDLE 40S ACROSS THE EAST WHERE
CLOUDS WILL EXIT LAST...TO THE LOWER/MID 50S ACROSS PORTIONS OF
NORTHEAST IA/SOUTHEAST MINNESOTA.
WEAK HIGH PRESSURE WILL DRIFT EAST ACROSS THE AREA FRIDAY NIGHT FOR
MOSTLY CLEAR SKIES WITH LIGHT PREVAILING SOUTHWEST WINDS.
ANOTHER STRONGER AREA OF LOW PRESSURE WILL MOVE OUT OF THE CENTRAL
PRAIRIE PROVINCES OF CANADA INTO MANITOBA ON SATURDAY. A COLD FRONT
WILL EXTEND SOUTH FROM THIS LOW THROUGH WESTERN MN INTO EASTERN
NEBRASKA. MODELS ARE DEPICTING AN INCREASE IN 925-850MB TRANSPORT
AHEAD OF THE COLD FRONT INTO THE AREA BY SATURDAY AFTERNOON. THE GFS
IS THE ONLY MODEL THAT PRODUCES SOME STRATUS AS IMPLIED BY RH FIELDS
AND DECREASING CONDENSATION DEFICITS ON THE 290K SURFACE. REST OF
THE MODELS SHOW SOME INCREASE IN MID/HIGH CLOUDS THROUGH THE DAY. AS
A RESULT...WILL GO WITH PARTLY/MOSTLY SUNNY CONDITIONS THROUGH THE
DAY. BREEZY AHEAD OF THE FRONT WILL DRAW IN WARMER AIR WITH
925-850MB TEMPERATURES INCREASING INTO THE 5-9C RANGE. THIS SHOULD
BE GOOD ENOUGH FOR HIGHS IN THE LOWER TO MIDDLE 50S.
LOOK FOR THE COLD FRONT TO PUSH INTO/THROUGH THE AREA SATURDAY NIGHT
THROUGH SUNDAY FOR INCREASING CLOUDS SATURDAY NIGHT AND A CHANCE OF
RAIN SHOWERS ON SUNDAY. THERE MAY EVEN BE A SIGNAL FOR SOME LIGHT
DRIZZLE SATURDAY NIGHT...BUT COLUMN SATURATION IS QUESTIONABLE AT
THIS POINT...SO WILL LEAVE OUT FOR NOW. ALONG THE CLOUDS/SHOWER
CHANCES...LOOK FOR BREEZY SOUTH WINDS SATURDAY NIGHT TO SHIFT TO THE
SOUTHWEST WITH COLD AIR ADVECTION ON SUNDAY. HIGHS ON SUNDAY ONLY
EXPECTED TO TOP OFF IN THE MID 40S ACROSS THE NORTH...TO A FEW LOWER
50S ACROSS THE SOUTH.
THE COLD FRONT WILL SLIP SOUTHEAST OF THE AREA SUNDAY NIGHT. THE
GEM/ECMWF SHOW A WEAK MID-LEVEL SHORT WAVE TROUGH RIDING NORTHEAST
ALONG THE BAROCLINIC RIBBON...PUSHING RAIN INTO FAR SOUTHERN PORTIONS
OF THE FORECAST AREA. THE GFS SHOWS THE SAME WAVE...BUT A BIT
FARTHER SOUTH THUS KEEPING THE PRECIPITATION SOUTH OF THE AREA. AS
SUCH...WILL GO WITH A MODEL CONSENSUS AND INCLUDE SMALL RAIN CHANCES
SOUTH OF A MAUSTON/RICHLAND CENTER/POTOSI WI LINE.
.LONG TERM...MONDAY THROUGH THURSDAY
220 PM CST THU NOV 10 2011
10.12Z ECMWF/GEM CONTINUE TO SHOW A WEAK WAVE OF LOW PRESSURE
RIPPLING NORTHEAST ACROSS REGION WITH THE ECMWF ON A MORE NORTHWEST
TRACK. MEANWHILE...THE GFS THE BAROCLINIC RIBBON/WAVE WAY OFF TO THE
EAST OVER THE EASTERN GREAT LAKES. DUE TO THE VARIABILITY BETWEEN
THE MODELS WILL LET MODEL CONSENSUS PREVAIL WHICH YIELDS A SMALL
CHANCE OF RAIN ACROSS THE SOUTHEAST HALF OF THE FORECAST AREA.
MEDIUM RANGE MODELS CONTINUE TO SHOW A SHALLOW TROUGH OF LOW
PRESSURE ACROSS THE CENTRAL CONUS THROUGH THE REST OF THE
PERIOD...BUT DIFFER ON SMALLER SCALE SHORT WAVE ENERGY RIPPLING
THROUGH A RATHER FAST FLOW ALOFT. MODELS CONSENSUS KEEPS US DRY
THROUGH THE PERIOD WITH VARYING DEGREE OF CLOUD COVER.
OTHERWISE...TEMPERATURES THROUGH THE PERIOD LOOK TO BE COOLER THAN
NORMAL WITH HIGHS MONDAY AND TUESDAY IN THE 40S...AND IN THE MIDDLE
30S/LOWER 40S WEDNESDAY AND THURSDAY.
&&
.AVIATION...THROUGH 06Z SATURDAY
1114 PM CST THU NOV 10 2011
MAIN FOCUS FOR THIS SET OF TAFS IS WITH CLOUD COVER AND WINDS AS
THE NEXT SYSTEM DROPS DOWN INTO THE UPPER GREAT LAKES. THE BACK
EDGE OF A 4KFT CLOUD DECK HAS MOVED EAST OF LSE WHILE A 7-15KFT
DECK MOVES IN FROM THE WEST AHEAD OF THE NEXT SYSTEM. 00Z UPPER
AIR SOUNDINGS FROM ABR AND MPX SHOW A DRY LAYER FROM ABOUT 800MB
DOWN TO THE SURFACE WHICH IS KEEPING ANY OF THE PRECIPITATION FROM
REACHING THE GROUND. AM EXPECTING THIS TREND TO CONTINUE THROUGH
THE NIGHT INTO TOMORROW MORNING BEFORE THIS CLOUD COVER MOVES TO
THE EAST AND SKIES CLEAR LATER IN THE AFTERNOON. WINDS HAVE
ALREADY STARTED THEIR SHIFT TOWARD THE SOUTH AND WILL LIKELY
BECOME GUSTY LATER IN THE MORNING AND EARLY AFTERNOON WITH SOME
GUSTS UP AROUND 20 TO 25KTS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
220 PM CST THU NOV 10 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH/DAS
LONG TERM...DAS
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
914 PM CST THU NOV 10 2011
.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
914 PM CST THU NOV 10 2011
MAIN FOCUS THIS EVENING HAS BEEN WITH WHETHER ANY LIGHT SNOW WOULD
HAVE TO BE ADDED TO THE FORECAST AFTER MIDNIGHT WITH THE NEXT
SYSTEM DROPPING THROUGH THE DAKOTAS. WITH ISENTROPIC LIFT ON THE
285K TO 290K SURFACE AND 850MB WARM AIR ADVECTION KICKING
IN...CLOUDS HAVE REFORMED ACROSS THE EASTERN DAKOTAS AND WESTERN
MINNESOTA. WHILE SOME RETURNS HAVE POPPED UP ACROSS THIS
REGION...THE LOW LEVEL REMAIN FAIRLY DRY PER 11.00Z ABR AND MPX
SOUNDINGS WITH NONE OF THE AUTOMATED SITES OUT THERE REPORTING
PRECIPITATION. 11.00Z NAM AND 11.01Z RUC SOUNDINGS FOR ACROSS THE
REGION SHOW THE RAPID MOISTENING ABOVE 800MB TONIGHT BUT A DRY
LAYER JUST BELOW THIS WITH DEW POINT DEPRESSIONS OF ABOUT 20C
AROUND 850MB. THUS...WHILE RADAR RETURNS WILL LIKELY BE SHOWING UP
TONIGHT ACROSS THE REGION...AM NOT EXPECTING ANY SNOW TO MAKE IT
DOWN TO THE GROUND. THE LONE EXCEPTION MAY BE ACROSS PARTS OF
NORTHERN WISCONSIN TOWARD DAYBREAK WHEN THE MID LEVEL SHORTWAVE
TROUGH AND PV ADVECTION DROPS DOWN BUT NOT EXPECTING MUCH IF ANY
ACCUMULATION.
HAVE ALSO TRENDED TOWARD A MORE CLOUDY SOLUTION OVERNIGHT WITH THE
MID LEVEL DECK HOLDING ON STRONG THROUGH MUCH OF WISCONSIN AND
HIGH LEVEL CLOUD COVER COMING IN AHEAD OF THE NEXT SYSTEM.
FROM PREVIOUS DISCUSSION...
FOR FRIDAY...CONTINUED ISENTROPIC LIFT IN THE MORNING/COUPLED WITH
WEAK 500-300MB PV-ADVECTION COULD BE ENOUGH TO FULLY SATURATE THE
COLUMN MAINLY ALONG/NORTH OF I-94. THERE IS STILL SOME QUESTION AS
TO HOW DRY THE SUB CLOUD LAYER WILL REMAIN...WITH THE NAM SHOWING
STRONGEST DEGREE OF SATURATION WHILE OTHER MODELS SHOW LESS. AS
SUCH...WILL INCLUDE A 20 POP FOR SNOW EARLY ON IN THE MORNING...
POSSIBLY MIXING/CHANGING TO RAIN LATER IN THE MORNING. BY FRIDAY
AFTERNOON...THE WARM FRONT/CLOUDS/PRECIPITATION CHANCES PUSH
EAST...LEAVING THE AREA IN THE SUNNY WARM SECTOR OF THE LOW WHICH
WILL BE OVER CENTRAL LAKE SUPERIOR. BREEZY SOUTHWEST WINDS DRAW IN
WARMER AIR...WITH THE 925-850MB TEMPERATURES INCREASING INTO THE 5
TO 8C RANGE BY LATE IN THE AFTERNOON WITH FULL SUNSHINE. THIS IS
EXPECTED TO YIELD HIGHS IN THE MIDDLE 40S ACROSS THE EAST WHERE
CLOUDS WILL EXIT LAST...TO THE LOWER/MID 50S ACROSS PORTIONS OF
NORTHEAST IA/SOUTHEAST MINNESOTA.
WEAK HIGH PRESSURE WILL DRIFT EAST ACROSS THE AREA FRIDAY NIGHT FOR
MOSTLY CLEAR SKIES WITH LIGHT PREVAILING SOUTHWEST WINDS.
ANOTHER STRONGER AREA OF LOW PRESSURE WILL MOVE OUT OF THE CENTRAL
PRAIRIE PROVINCES OF CANADA INTO MANITOBA ON SATURDAY. A COLD FRONT
WILL EXTEND SOUTH FROM THIS LOW THROUGH WESTERN MN INTO EASTERN
NEBRASKA. MODELS ARE DEPICTING AN INCREASE IN 925-850MB TRANSPORT
AHEAD OF THE COLD FRONT INTO THE AREA BY SATURDAY AFTERNOON. THE GFS
IS THE ONLY MODEL THAT PRODUCES SOME STRATUS AS IMPLIED BY RH FIELDS
AND DECREASING CONDENSATION DEFICITS ON THE 290K SURFACE. REST OF
THE MODELS SHOW SOME INCREASE IN MID/HIGH CLOUDS THROUGH THE DAY. AS
A RESULT...WILL GO WITH PARTLY/MOSTLY SUNNY CONDITIONS THROUGH THE
DAY. BREEZY AHEAD OF THE FRONT WILL DRAW IN WARMER AIR WITH
925-850MB TEMPERATURES INCREASING INTO THE 5-9C RANGE. THIS SHOULD
BE GOOD ENOUGH FOR HIGHS IN THE LOWER TO MIDDLE 50S.
LOOK FOR THE COLD FRONT TO PUSH INTO/THROUGH THE AREA SATURDAY NIGHT
THROUGH SUNDAY FOR INCREASING CLOUDS SATURDAY NIGHT AND A CHANCE OF
RAIN SHOWERS ON SUNDAY. THERE MAY EVEN BE A SIGNAL FOR SOME LIGHT
DRIZZLE SATURDAY NIGHT...BUT COLUMN SATURATION IS QUESTIONABLE AT
THIS POINT...SO WILL LEAVE OUT FOR NOW. ALONG THE CLOUDS/SHOWER
CHANCES...LOOK FOR BREEZY SOUTH WINDS SATURDAY NIGHT TO SHIFT TO THE
SOUTHWEST WITH COLD AIR ADVECTION ON SUNDAY. HIGHS ON SUNDAY ONLY
EXPECTED TO TOP OFF IN THE MID 40S ACROSS THE NORTH...TO A FEW LOWER
50S ACROSS THE SOUTH.
THE COLD FRONT WILL SLIP SOUTHEAST OF THE AREA SUNDAY NIGHT. THE
GEM/ECMWF SHOW A WEAK MID-LEVEL SHORT WAVE TROUGH RIDING NORTHEAST
ALONG THE BAROCLINIC RIBBON...PUSHING RAIN INTO FAR SOUTHERN PORTIONS
OF THE FORECAST AREA. THE GFS SHOWS THE SAME WAVE...BUT A BIT
FARTHER SOUTH THUS KEEPING THE PRECIPITATION SOUTH OF THE AREA. AS
SUCH...WILL GO WITH A MODEL CONSENSUS AND INCLUDE SMALL RAIN CHANCES
SOUTH OF A MAUSTON/RICHLAND CENTER/POTOSI WI LINE.
.LONG TERM...MONDAY THROUGH THURSDAY
220 PM CST THU NOV 10 2011
10.12Z ECMWF/GEM CONTINUE TO SHOW A WEAK WAVE OF LOW PRESSURE
RIPPLING NORTHEAST ACROSS REGION WITH THE ECMWF ON A MORE NORTHWEST
TRACK. MEANWHILE...THE GFS THE BAROCLINIC RIBBON/WAVE WAY OFF TO THE
EAST OVER THE EASTERN GREAT LAKES. DUE TO THE VARIABILITY BETWEEN
THE MODELS WILL LET MODEL CONSENSUS PREVAIL WHICH YIELDS A SMALL
CHANCE OF RAIN ACROSS THE SOUTHEAST HALF OF THE FORECAST AREA.
MEDIUM RANGE MODELS CONTINUE TO SHOW A SHALLOW TROUGH OF LOW
PRESSURE ACROSS THE CENTRAL CONUS THROUGH THE REST OF THE
PERIOD...BUT DIFFER ON SMALLER SCALE SHORT WAVE ENERGY RIPPLING
THROUGH A RATHER FAST FLOW ALOFT. MODELS CONSENSUS KEEPS US DRY
THROUGH THE PERIOD WITH VARYING DEGREE OF CLOUD COVER.
OTHERWISE...TEMPERATURES THROUGH THE PERIOD LOOK TO BE COOLER THAN
NORMAL WITH HIGHS MONDAY AND TUESDAY IN THE 40S...AND IN THE MIDDLE
30S/LOWER 40S WEDNESDAY AND THURSDAY.
&&
.AVIATION...TONIGHT AND SATURDAY
607 PM CST THU NOV 10 2011
THE MAIN FOCUS OF THE 00Z TAFS IS WITH THE LINGERING 4-5KFT DECK
AND WHEN THEY WILL DIMINISH IN COVERAGE THIS EVENING. AT 00Z...THE
BACK EDGE OF THIS VFR CLOUD DECK WAS SLOWLY MOVING EAST ACROSS
EASTERN MINNESOTA AND IS EXPECTED TO BE THROUGH RST BY 4Z AND LSE
BY 7Z. HIGH LEVEL CLOUD COVER WILL BE QUICK ON THE HEELS OF THIS
RETREATING MID LEVEL CLOUD DECK AS A SYSTEM DROPS DOWN OUT OF
MANITOBA INTO THE UPPER GREAT LAKES. WINDS WILL BE MAKING A
COMPLETE SHIFT FROM THE NORTHWEST TO THE SOUTH BY TOMORROW MORNING
AND WILL LIKELY BECOME GUSTY TO 20-25KTS TOMORROW AFTERNOON.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
220 PM CST THU NOV 10 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH/DAS
LONG TERM...DAS
AVIATION...HALBACH