Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 01/15/12
AREA FORECAST DISCUSSION
NWS DENVER CO
1032 AM MST FRI JAN 13 2012
.UPDATE...CURRENT FORECAST STILL ON TRACK AS NORTHWEST FLOW ALOFT
PERSISTS. GUSTY WINDS TO CONTINUE ACROSS MUCH OF THE AREA THROUGH
THE AFTERNOON WITH THE STRONGEST GUSTS OVER THE MOUNTAINS AND
ALONG THE FOOTHILLS. GUIDANCE AS WELL AS LOCAL SANGTER WIND MODEL SHOWING
WINDS TO REMAIN BELOW HIGH WIND CRITERIA. MODELS SHOW SOME
WEAKENING OF THE WINDS ACROSS PLAINS BY THIS EVENING...STILL
REMAINING GUSTY ALONG FOOTHILLS AND MOUNTAINS. ALL THIS REFLECTED
IN CURRENT GRIDS.
&&
.AVIATION...CURRENT TAF TRENDS STILL ON TRACK. LATEST RUC AND HRRR
STILL SHOW THAT PUSH OF NORTHWEST WINDS ACROSS THE AREA BETWEEN 20Z
AND 23Z. DID INCREASE THE WINDS A BIT OVERNIGHT AS SURFACE
GRADIENT SUGGESTS A BIT OF ENHANCED DRAINAGE.
&&
.PREV DISCUSSION... /ISSUED 321 AM MST FRI JAN 13 2012/
SHORT TERM...NW FLOW ALOFT WILL REMAIN OVER THE AREA THRU TONIGHT.
QUITE A BIT OF HIGHER LEVEL MOISTURE WILL MOVE ACROSS THE AREA TODAY
WITH PERIODS OF HIGHER LEVEL CLOUDS THRU THIS AFTN BUT NO PCPN.
CROSS-SECTIONS SHOW GUSTY NWLY WINDS WILL OCCUR IN THE
MTNS...FOOTHILLS AND ACROSS THE NERN PLAINS ESPECIALLY NR THE WY-NE
BORDER AREA. GUSTS MAY REACH THE 40-45 MPH RANGE THIS AFTN NR THE
WY-NE BORDER WITH 55-60 MPH IN THE FOOTHILLS AND HIGHER MTNS. AT
THIS TIME WINDS SHOULD STAY BLO WARNING CRITERIA. OTHER CONCERN
WOULD BE FIRE WEATHER POTENTIAL OVER PARTS OF THE NERN PLAINS
HOWEVER MODELS ARE SHOWING VARYING HUMIDITY LEVELS THIS AFTN SO NOT
SURE WHICH SOLUTIONS ARE RIGHT. THERE MAY BE A SMALL 3 HOUR WINDOW
FROM 20Z-23Z WHERE CONDITIONS MAY BE MET MAINLY ALONG THE WY-NE
BORDER. AS FAR AS TEMPS SHOULD CONTINUE TO SEE WARMER READINGS WITH
HIGHS IN THE 45 TO 50 DEGREE RANGE ACROSS NERN CO.
FOR TONIGHT NW FLOW WILL CONTINUE HOWEVER HIGHER LEVEL MOISTURE WILL
DECREASE SO HIGH LEVEL CLOUDINESS SHOULD DIMINISH. CROSS-SECTIONS
CONTINUE TO SHOW GUSTY WINDS OVER THE HIGHER MTNS AND FOOTHILLS
OVERNIGHT BUT SPEEDS SHOULD REMAIN BLO WARNING CRITERIA.
LONG TERM....UPPER RIDGING DOMINATES THE FORECAST AREA INTO MID DAY
SUNDAY...WITH NORTHWESTERLY FLOW ALOFT SATURDAY...BECOMING ZONAL
SATURDAY NIGHT INTO SUNDAY. BY LATER SUNDAY AFTERNOON AND NIGHT
..THE FLOW ALOFT BECOMES SOUTHWESTERLY WITH AN UPPER TROUGH MOVING
INTO THE GREAT BASIN FROM THE NORTHWEST. THE SYNOPTIC SCALE ENERGY
IS BENIGN SATURDAY INTO SUNDAY AFTERNOON...THEN WEAK QG ASCENT MOVES
IN LATE. BY MONDAY MORNING...THE UPWARD VERTICAL VELOCITY IS
PROGGED TO INCREASE. THE BOUNDARY LAYER FLOW WILL LIKELY BE
DOWNSLOPING IN NATURE SATURDAY THROUGH SUNDAY...WITH LOW LEVEL
TROUGHING EAST OF THE MOUNTAINS ALL WEEKEND. FOR MOISTURE...THERE
IS SOME IN THE MID AND UPPER LEVELS SATURDAY THROUGH SUNDAY...MORE
SO ON THE GFS. AFTER 06Z SUNDAY NIGHT...BOTH MODELS INCREASE
MOISTURE DRAMATICALLY OVER THE MOUNTAINS. THE QPF FIELDS SHOW NO
MEASURABLE PRECIPITATION OVER THE CWA SATURDAY THROUGH MIDNIGHT
SUNDAY NIGHT. THERE IS A TAD OVER THE MOUNTAINS WEST OF THE DIVIDE
PROGGED FROM 06Z TO 12Z MONDAY MORNING. NO POPS THROUGH SUNDAY
EVENING...THEN 20%S IN THE HIGH MOUNTAINS OVERNIGHT SUNDAY. FOR
TEMPERATURES...SATURDAY`S HIGHS ARE 3-4.5 C WARMER THAN TODAY`S.
SUNDAY`S HIGHS ARE 1-3 C WARMER THAN SATURDAY`S. FOR THE LATER
DAYS...MONDAY THROUGH THURSDAY...THE NAM...GFS...AND ECMWF ALL SHOW
AN UPPER TROUGH TO MOVE ACROSS THE CWA LATER MONDAY AND MONDAY
NIGHT. THERE IS MOISTURE...COLD AIR...AND UPSLOPE FOR THE PLAINS
AND FOOTHILLS. HOWEVER IT IS A QUICK SHOT. AFTER THE TROUGH AXIS
MOVES THROUGH...PRETTY STRONG NORTHWESTERLY FLOW ALOFT IS PROGGED TO
CONTINUE MUCH OF NEXT WEEK. THE GFS SHOWS FAIRLY DECENT MOISTURE IN
THE FLOW...BUT THE ECMWF HAS LESS. THIS TYPE OF PATTERN WOULD FAVOR
MOUNTAIN SNOWS OFF AND ON. WE`LL SEE. MONDAY AND TUESDAY LOOK
PRETTY COLD...WITH WARMING FOR WEDNESDAY AND THURSDAY.
AVIATION...OUTSIDE OF SOME HIGHER LEVEL CLOUDS VFR CONDITIONS WILL
BE IN PLACE THRU TONIGHT. WINDS THIS MORNING WILL BE SSW BUT WILL
SHIFT TO MORE WLY BY 17Z. IN THE AFTN BOTH THE RUC AND HRRR SO
A SURGE OF STRONGER WINDS COMING OFF THE FOOTHILLS FM THE WNW AROUND
20Z WITH GUSTS OF 25-30 MPH POSSIBLE FM 20Z-23Z. BY EARLY EVENING
WINDS SHOULD GRADUALLY BECOME MORE WSW WITH DECREASING SPEEDS AND
THEN WILL BECOME MORE SSW BY 06Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RJK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS DENVER CO
321 AM MST FRI JAN 13 2012
.SHORT TERM...NW FLOW ALOFT WILL REMAIN OVER THE AREA THRU TONIGHT.
QUITE A BIT OF HIGHER LEVEL MOISTURE WILL MOVE ACROSS THE AREA TODAY
WITH PERIODS OF HIGHER LEVEL CLOUDS THRU THIS AFTN BUT NO PCPN.
CROSS-SECTIONS SHOW GUSTY NWLY WINDS WILL OCCUR IN THE
MTNS...FOOTHILLS AND ACROSS THE NERN PLAINS ESPECIALLY NR THE WY-NE
BORDER AREA. GUSTS MAY REACH THE 40-45 MPH RANGE THIS AFTN NR THE
WY-NE BORDER WITH 55-60 MPH IN THE FOOTHILLS AND HIGHER MTNS. AT
THIS TIME WINDS SHOULD STAY BLO WARNING CRITERIA. OTHER CONCERN
WOULD BE FIRE WEATHER POTENTIAL OVER PARTS OF THE NERN PLAINS
HOWEVER MODELS ARE SHOWING VARYING HUMIDITY LEVELS THIS AFTN SO NOT
SURE WHICH SOLUTIONS ARE RIGHT. THERE MAY BE A SMALL 3 HOUR WINDOW
FROM 20Z-23Z WHERE CONDITIONS MAY BE MET MAINLY ALONG THE WY-NE
BORDER. AS FAR AS TEMPS SHOULD CONTINUE TO SEE WARMER READINGS WITH
HIGHS IN THE 45 TO 50 DEGREE RANGE ACROSS NERN CO.
FOR TONIGHT NW FLOW WILL CONTINUE HOWEVER HIGHER LEVEL MOISTURE WILL
DECREASE SO HIGH LEVEL CLOUDINESS SHOULD DIMINISH. CROSS-SECTIONS
CONTINUE TO SHOW GUSTY WINDS OVER THE HIGHER MTNS AND FOOTHILLS
OVERNIGHT BUT SPEEDS SHOULD REMAIN BLO WARNING CRITERIA.
.LONG TERM....UPPER RIDGING DOMINATES THE FORECAST AREA INTO MID DAY
SUNDAY...WITH NORTHWESTERLY FLOW ALOFT SATURDAY...BECOMING ZONAL
SATURDAY NIGHT INTO SUNDAY. BY LATER SUNDAY AFTERNOON AND NIGHT
...THE FLOW ALOFT BECOMES SOUTHWESTERLY WITH AN UPPER TROUGH MOVING
INTO THE GREAT BASIN FROM THE NORTHWEST. THE SYNOPTIC SCALE ENERGY
IS BENIGN SATURDAY INTO SUNDAY AFTERNOON...THEN WEAK QG ASCENT MOVES
IN LATE. BY MONDAY MORNING...THE UPWARD VERTICAL VELOCITY IS
PROGGED TO INCREASE. THE BOUNDARY LAYER FLOW WILL LIKELY BE
DOWNSLOPING IN NATURE SATURDAY THROUGH SUNDAY...WITH LOW LEVEL
TROUGHING EAST OF THE MOUNTAINS ALL WEEKEND. FOR MOISTURE...THERE
IS SOME IN THE MID AND UPPER LEVELS SATURDAY THROUGH SUNDAY...MORE
SO ON THE GFS. AFTER 06Z SUNDAY NIGHT...BOTH MODELS INCREASE
MOISTURE DRAMATICALLY OVER THE MOUNTAINS. THE QPF FIELDS SHOW NO
MEASURABLE PRECIPITATION OVER THE CWA SATURDAY THROUGH MIDNIGHT
SUNDAY NIGHT. THERE IS A TAD OVER THE MOUNTAINS WEST OF THE DIVIDE
PROGGED FROM 06Z TO 12Z MONDAY MORNING. NO POPS THROUGH SUNDAY
EVENING...THEN 20%S IN THE HIGH MOUNTAINS OVERNIGHT SUNDAY. FOR
TEMPERATURES...SATURDAY`S HIGHS ARE 3-4.5 C WARMER THAN TODAY`S.
SUNDAY`S HIGHS ARE 1-3 C WARMER THAN SATURDAY`S. FOR THE LATER
DAYS...MONDAY THROUGH THURSDAY...THE NAM...GFS...AND ECMWF ALL SHOW
AN UPPER TROUGH TO MOVE ACROSS THE CWA LATER MONDAY AND MONDAY
NIGHT. THERE IS MOISTURE...COLD AIR...AND UPSLOPE FOR THE PLAINS
AND FOOTHILLS. HOWEVER IT IS A QUICK SHOT. AFTER THE TROUGH AXIS
MOVES THROUGH...PRETTY STRONG NORTHWESTERLY FLOW ALOFT IS PROGGED TO
CONTINUE MUCH OF NEXT WEEK. THE GFS SHOWS FAIRLY DECENT MOISTURE IN
THE FLOW...BUT THE ECMWF HAS LESS. THIS TYPE OF PATTERN WOULD FAVOR
MOUNTAIN SNOWS OFF AND ON. WE`LL SEE. MONDAY AND TUESDAY LOOK
PRETTY COLD...WITH WARMING FOR WEDNESDAY AND THURSDAY.
&&
.AVIATION...OUTSIDE OF SOME HIGHER LEVEL CLOUDS VFR CONDITIONS WILL
BE IN PLACE THRU TONIGHT. WINDS THIS MORNING WILL BE SSW BUT WILL
SHIFT TO MORE WLY BY 17Z. IN THE AFTN BOTH THE RUC AND HRRR SO
A SURGE OF STRONGER WINDS COMING OFF THE FOOTHILLS FM THE WNW AROUND
20Z WITH GUSTS OF 25-30 MPH POSSIBLE FM 20Z-23Z. BY EARLY EVENING
WINDS SHOULD GRADUALLY BECOME MORE WSW WITH DECREASING SPEEDS AND
THEN WILL BECOME MORE SSW BY 06Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
RPK/RJK
AREA FORECAST DISCUSSION
NWS ALBANY NY
539 PM EST FRI JAN 13 2012
.SYNOPSIS...
LOW PRESSURE WILL DEEPEN AND INTENSIFY...AS IT MOVES
INTO THE CANADIAN MARITIMES TONIGHT. BLUSTERY AND COLD CONDITIONS
WILL CONTINUE OVERNIGHT WITH OCCASIONAL SNOW SHOWERS AND
FLURRIES...AS AN ARCTIC COLD FRONT MOVES THROUGH TOWARDS DAYBREAK.
ARCTIC HIGH PRESSURE WILL BUILD IN FROM SOUTHEASTERN ONTARIO LATE
SATURDAY INTO SUNDAY WITH SUBSIDING WINDS...BUT FRIGID TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 530 PM EST...WE ARE RECEIVING REPORTS OF 5-7 INCHES OF
SNOWFALL...AND UPSLOPE SNOWFALL IS REALLY CRANKING UP NOW ALONG
THE NRN-CNTRL TACONICS...BERKSHIRES AND SRN GREENS. WE JUST
RECEIVED A REPORT OF 5" IN DALTON...6.5" IN PITTSFIELD...7 INCHES IN SAVOY
AND LENOX...AND 6.5 INCHES IN WOODFORD VT. WE HAVE INCREASED NRN
BERKSHIRE CTY...BENNINGTON...AND WRN WINDHAM CTY VT TO WINTER
STORM WARNINGS FOR 6-12 INCHES OF HEAVY SNOW AND BLOWING SNOW. THE
UPSLOPE SNOWFALL LOOKS CLASSIC RIGHT NOW BASED ON THE KENX RADAR
RETURNS EAST OF THE I-90 CORRIDOR...AND NOW THAT THE UPPER LOW IS
OVER MAINE COUPLED WITH A SFC TROUGH MOVING OVER THE REGION. WE
INCREASED THE ADVISORY AMOUNTS FOR ERN RENSSELAER AND ERN COLUMBIA
COUNTIES TO 4-8" TOO.
PREVIOUS NEAR TERM...
AS OF 4 PM EST...THE WATER VAPOR LOOP THIS AFTERNOON HAS THE
POTENT H500 CLOSED LOW MOVING EAST OF NY INTO NEW ENGLAND. AN
IMPRESSIVE 125+KT H500 JET STREAK CONTINUES TO MOVE EAST OF NEW
ENGLAND THIS AFTERNOON. THE OCCLUDED FRONT TO THE INTENSIFYING SFC
LOW OVER SE QUEBEC BLASTED THROUGH THIS MORNING...WHICH HAS KICKED
OFF SOME SNOW SQUALLS...AND UPSLOPE SNOWFALL ALONG THE WRN SPINE
OF THE SRN GREENS MTNS...CNTRL-NRN TACONICS...AND THE BERKSHIRES.
THE LOW TO THE MID LEVEL DEFORMATION ZONE TO THE POTENT UPPER LOW
HAS CONTINUED THE SNOWFALL ALONG THE WRN DACKS...AND WRN-CNTRL MOHAWK
VALLEY.
THE UPSLOPE SNOWFALL IN ERN COLUMBIA...ERN RENSSELAER AND N-CNTRL
BERKSHIRE COUNTIES HAS BEEN IMPRESSIVE THIS AFTERNOON WITH A
REPORT OF 6 INCHES AT PERU IN THE BERKSHIRES AS OF 3 PM. SOME OF
THE KEY FEATURES FOR AN UPSLOPE SUBSYNOPTIC SNOWFALL EVENT WITH A
CLOSED LOW WERE IN PLACE WITH STRONG CYCLONIC VORTICITY
ADVECTION...COLD ADVECTION IN THE LOW LEVELS...MOIST LOW TO MID
LEVELS...AND PERSISTENT W/SW FLOW. USUALLY THIS OCCURS WHEN THE
UPPER LOW IS EAST OR NORTHEAST OF THE REGION PER THE BTV CSTAR
WORK. THIS IS A HYBRID TYPE CASE. THE LATEST FROM THE NAM12 AND
HRRR 3KM REF PRODUCT HAS THE SNOWFALL WINDING DOWN BETWEEN 00Z-
03Z. WE EXPANDED THE ADVISORY TO INCLUDE SRN BERKSHIRE CTY /JUST
NORTH THE MASS PIKE/...AS WELL AS INCLUDING THE NRN-CNTRL TACONICS.
THE SNOW REPORTS HAVE RANGED FROM 1-3 INCHES SO FAR IN
HERKIMER COUNTY AND SW HAMILTON CTY. SOME LAKE MOISTURE WILL
CONTINUE TO BE UTILIZED IN THE DEFORMATION ZONE. OROGRAPHIC
ENHANCEMENT WILL CONTINUE ALONG THE WRN DACKS. WE HAVE EXTENDED
THE WINTER WEATHER ADVISORY FOR THE SRN DACKS AND THE WRN MOHAWK
VALLEY UNTIL MIDNIGHT. BLUSTERY W/SW WINDS WILL PERSIST THIS
EVENING BLOWING THE SNOW AROUND. THE BETTER LIFT AND MOISTURE
CONVERGENCE HAS BEEN CLOSER TO THE LAKE SHORE AND OVER W-CNTRL NY
TODAY. WE PLACED THE HIGHEST SNOW TOTALS THERE OVER NRN HERKIMER
CTY WITH 4 TO 8 INCHES...AND HAVE GONE 3 TO 6 INCHES ELSEWHERE.
LOOKING AT THE BUFKIT SOUNDINGS FROM KSYR...KUCA...AND KRME...THE
INVERSION DOES LOWER TO 4-5 KFT AGL OVERNIGHT WHICH WILL DIMINISH
THE SNOW...AND THE SFC TO BOUNDARY LAYER FLOW BEGINS TO VEER MORE
TO THE NW /CLOSE TO A 300 DEGREE TRAJECTORY/ WITH THE PASSAGE OF
ANOTHER COLD FRONT /THE LEADING EDGE OF ARCTIC AIR/. THERE COULD BE
A QUICK LAKE EXTENSION DOWN THE MOHAWK VALLEY FOR SOME SCT SNOW
SHOWERS TOWARDS DAYBREAK. THE HRRR HINTS AT HIS POSSIBILITY. WE
WILL HAVE TO MONITOR IF THIS MATERIALIZES.
IN TERMS OF THE WIND ADVISORY...GUSTS HAVE GENERALLY BEEN 30-35
KTS...JUST SHORT OF WIND ADVISORY CRITERIA. HOWEVER...AS OF 4 PM
KALB JUST HAD A GUST TO 36 KTS...AND THE H925 WINDS DO INCREASE TO
35-40 KTS...AND THE H850 WINDS TO 50-60 KTS BY 00Z. WE ARE
CONCERNED A FEW GUSTS COULD REACH 40 KTS OR SO..IF WE MIX TO H925. THE
LOW LEVEL PRESSURE GRADIENT WILL BE INCREASING...AND THERE IS A SFC
TROUGH MOVING ACROSS THE REGION AT 21Z PER THE RUC. WE WILL KEEP
THE WIND ADVISORY UP UNTIL MIDNIGHT. THE WINDS WILL GRADUALLY EASE
SLIGHTLY AFTER MIDNIGHT FROM THE W AT 15-25 MPH WITH SOME GUSTS
AROUND 35 MPH.
A BATCH OF SNOW SHOWERS OR SQUALLS WILL MOVE ACROSS THE REGION
BWTN 21Z-00Z. THIS COULD PRODUCE A DUSTING TO A FEW INCHES OF
SNOWFALL IN THE NON-ADVISORY AREAS FROM THE CAPITAL REGION NORTH.
LOWS TONIGHT WILL BE CHILLY WITH 5-10F READINGS OVER THE
ADIRONDACK PARK...TEENS ELSEWHERE..EXCEPT LOWER TO MID 20S FROM
KALB SOUTH DOWN THE HUDSON RIVER VALLEY...AND EAST OF THE GREEN
MTNS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
SATURDAY...ANOTHER BOUNDARY MOVES THROUGH DURING THE MORNING...AS
THE SFC TO BOUNDARY LAYER FLOW CONTINUES TO VEER TO THE NORTHWEST.
THERE MAYBE A FEW MULTIBANDS OFF LAKE ONTARIO MAINLY IMPACTING
CNTRL NY. THE BEST CHC OF ISOLATED TO SCT SNOW SHOWERS AND
FLURRIES WILL BE WEST OF THE HUDSON RIVER VALLEY. THE STRONG
SUBSIDENCE FROM THE ARCTIC HIGH BUILDING IN WILL TEND TO SQUASH ANY
FURTHER DEVELOPMENT OF THE LAKE EFFECT SNOW GETTING INTO MOST OF
THE REGION. ANY ACCUMULATIONS FOR THE WRN MOHAWK VALLEY/ERN
CATSKILLS SHOULD BE LIGHT. OTHERWISE...COLD ADVECTION CONTINUES
OVER THE REGION WITH H850 TEMPS FALLING TO -15C TO -20C. MAX
TEMPS WILL OCCUR EARLY TOMORROW WITH HIGHS IN THE 25-30F RANGE
SOUTH AND EAST OF THE CAPITAL REGION...AND MIDS TEENS TO L20S
NORTH AND WEST...EXCEPT OVER THE SRN DACKS...WHERE SOME SINGLE
DIGITS AND LOWER TEENS WILL BE COMMON. IT WILL STILL BE BLUSTERY
WITH WINDCHILLS IN THE SINGLE DIGITS AND TEENS...AND BELOW ZERO
NORTH AND WEST OF THE CAPITAL REGION.
SATURDAY NIGHT...TRICKY FORECAST HOW FAST THE WINDS DECOUPLE WITH
THE ARCTIC HIGH BUILDING IN. WE COULD FLIRT WITH SOME ADVISORY
LEVELS WIND CHILLS OVER THE SRN DACKS...IF WE MAINTAIN WINDS IN
EXCESS OF 5 MPH. WE WILL CONTINUE THE PREVIOUS FORECASTS MENTION
IN THE HWO. OVERALL...A BITTERLY COLD NIGHT IS EXPECTED WITH LOWS
IN THE SINGLE DIGITS FROM THE CAPITAL DISTRICT SOUTH AND
EAST...AND ZERO TO 10 BELOW NORTH AND WEST...EXCEPT 10-20 BELOW IN
THE SRN DACKS.
SUNDAY-SUNDAY NIGHT...ARCTIC HIGH PRESSURE BUILDS OVER NY AND NEW
ENGLAND ON SUNDAY. MOSTLY SUNNY AND COLD CONDITIONS WILL PREVAIL
WITH HIGHS IN THE TEENS TO L20S OVER MOST OF THE REGION...EXCEPT
SOME SINGLE DIGITS OVER THE SRN DACKS...AND THE SRN GREENS. WE
START TO WARM ADVECT SUNDAY NIGHT...AS THE HIGH SLOWLY SHIFTS
DOWNSTREAM OVER NRN NEW ENGLAND. SOME CIRRUS MAY CREEP IN AHEAD OF
A WARM FRONT OVER THE GREAT LAKES REGION...AND SE ONTARIO. LOWS
WILL NOT BE AS COLD WITH MAINLY SINGLE DIGITS FROM THE MOHAWK
VALLEY...CAPITAL REGION SOUTH...AND SOME ZERO TO 10 BELOW READINGS
NORTH.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
A TRANQUIL WEATHER PATTERN ON MONDAY WILL TRANSITION TO A MORE
ACTIVE PATTERN TOWARD THE END OF THE WORK WEEK. A RIDGE LOOKS TO BE
IN PLACE MONDAY MORNING BUT AS THE DAY PROGRESSES...A SHORTWAVE
TROUGH IN THE MIDWEST WILL ACT TO SHIFT THE RIDGE FROM NORTHEAST
INTO THE ATLANTIC COAST. THIS SHORTWAVE WILL PROGRESS TO THE EAST
TOWARD EASTERN OHIO/W PA LATE TUESDAY INTO EARLY WEDNESDAY. THIS LOW
WILL PRODUCE WINDY CONDITIONS WITH SUSTAINED WNW WINDS AT 15-20 KTS
AND GUSTS 20-25 KTS THROUGH LATE WEDNESDAY.
THE ECMWF AND GFS BOTH SHOW THE POSITIVE TILTED TROUGH BECOMING A
NEGATIVE TROUGH OVER THE OHIO VALLEY WEDNESDAY MORNING...WITH
CYCLOGENESIS AT THE SFC OVER THE GREAT LAKES AREA AT THIS TIME. THE
MODELS AT THIS TIME SHOWS A DECENT LOW PRESSURE SYSTEM OVER THE
LAKES AND WESTERN NY MOVING NORTHEAST ALONG THE NY/CANADA BORDER. AT
THIS TIME...MODEL FORECAST SOUNDINGS SHOW THE PRECIPITATION TYPE
OVER THE FA STARTING OUT AS SNOW. BUT WITH TEMPERATURES WARMING
THROUGHOUT THE DAY...AREAS IN THE IMMEDIATE CAPITAL REGION AND SOUTH
WILL LIKELY CHANGE TO RAIN. AREAS NORTH OF ALB WILL SEE SNOW OR A
WINTRY MIX...DEPENDING ON ELEVATION.
THE GFS MODEL HAS THE SFC LOW PRESSURE SYSTEM MOVING OUT OF THE
NORTHEAST MOVING FASTER BUT ALL OF THE MODELS HAVE THE LOW PRESSURE
SYSTEMS OUT OF THE REGION BY LATE WEDNESDAY. THIS WILL BE FOLLOWED
BY ANOTHER SYSTEM...BUT MODELS LACKING CONSENSUS FOR LATE THURSDAY
INTO FRIDAY. GFS SHOWING NEGATIVELY TILTED UPPER LEVEL TROUGH WHICH
DEVELOPS A COASTAL LOW OFF OF CAPE COD. MEANWHILE THE ECMWF SHOW THE
UPPER LEVEL TROUGH HANGING BACK WEST...THEN RETREATING UP INTO
CANADA. WILL HAVE TO KEEP AN EYE AS THIS SYSTEM DEVELOPS.
NEAR NORMAL MAX TEMPS WILL WARM ON TUESDAY FROM A WARM FRONT AHEAD
OF THE APPROACHING LOW...TO 10 DEGREES ABOVE NORMAL. THIS WILL BE
FOLLOWED BY A COLD FRONT ON TUESDAY AND A STRONG NW FLOW PRODUCING
SLIGHTLY BELOW NORMAL TEMPERATURES THROUGH THE REST OF THE PERIOD.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
A STRENGTHENING LOW PRESSURE SYSTEM NEAR MONTREAL IS BRINGING VERY
WINDY AND MUCH COLDER AIR TO THE REGION THIS AFTERNOON...WITH
SCATTERED TO NUMEROUS SNOW SHOWERS EXPECTED...ESP AT KGFL AND KALB.
BOTH VSBYS AND CIGS COULD BECOME IFR IN ANY SNOW SHOWERS OR EMBEDDED
HEAVIER SQUALLS THIS AFTERNOON. CIGS AT KGFL AND KALB WILL LIKELY
REMAIN MVFR THIS EVENING AS COLD CYCLONIC FLOW CONTINUES. SCATTERED
SNOW SHOWERS WILL CONTINUE OVERNIGHT AS WELL ALTHOUGH THE BEST
CHANCE FOR STEADY SNOW IS THIS AFTERNOON AND EVENING. THE SNOW
SHOWERS SHOULD BECOME LESS NUMEROUS OVERNIGHT...ALTHOUGH MAY LINGER
AT KALB THROUGH DAYBREAK SATURDAY.
WINDS WILL BE WESTERLY AT 15-25 KT...WITH SOME STRONGER GUSTS
POSSIBLE...WINDS WILL REMAIN STRONG/GUSTY THROUGH THIS
EVENING...BEFORE DIMINISHING SLIGHTLY LATER THIS EVENING...ESP AT
KPOU.
OUTLOOK...
FRI NT...MAINLY MVFR...WINDY. SCATTERED -SHSN.
SAT-MON...VFR...NO SIG WX.
MON NT-TUE...MVFR...CHC IFR -SHSN/-FZRA.
WED...VFR. NO SIG WX.
&&
.HYDROLOGY...
NO MAJOR PROBLEMS ARE EXPECTED ON THE MAIN STEM RIVERS OVER THE
NEXT 5 DAYS. THE ARCTIC AIR MASS WILL ALLOW ICE TO FORM AND CONTINUE TO
THICKEN ON MAIN STEM RIVERS...LAKES...AND OTHER BODIES OF WATER
THROUGH THE WEEKEND. TEMPERATURES WILL MODERATE BACK ABOVE NORMAL
BY TUESDAY.
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...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR CTZ001-013.
NY...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ032-033-
038>043-047>054-058>061-063>066-082>084.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ032-
033-038-042-054-061.
MA...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ001-025.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ025.
WINTER STORM WARNING UNTIL MIDNIGHT EST TONIGHT FOR MAZ001.
VT...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VTZ013>015.
WINTER STORM WARNING UNTIL MIDNIGHT EST TONIGHT FOR VTZ013-014.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...KGM/LFM
AVIATION...SND
HYDROLOGY...WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
439 PM EST FRI JAN 13 2012
.SYNOPSIS...
LOW PRESSURE WILL DEEPEN AND INTENSIFY...AS IT MOVES
INTO THE CANADIAN MARITIMES TONIGHT. BLUSTERY AND COLD CONDITIONS
WILL CONTINUE OVERNIGHT WITH OCCASIONAL SNOW SHOWERS AND
FLURRIES...AS AN ARCTIC COLD FRONT MOVES THROUGH TOWARDS DAYBREAK.
ARCTIC HIGH PRESSURE WILL BUILD IN FROM SOUTHEASTERN ONTARIO LATE
SATURDAY INTO SUNDAY WITH SUBSIDING WINDS...BUT FRIGID TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 4 PM EST...THE WATER VAPOR LOOP THIS AFTERNOON HAS THE
POTENT H500 CLOSED LOW MOVING EAST OF NY INTO NEW ENGLAND. AN
IMPRESSIVE 125+KT H500 JET STREAK CONTINUES TO MOVE EAST OF NEW
ENGLAND THIS AFTERNOON. THE OCCLUDED FRONT TO THE INTENSIFYING SFC
LOW OVER SE QUEBEC BLASTED THROUGH THIS MORNING...WHICH HAS KICKED
OFF SOME SNOW SQUALLS...AND UPSLOPE SNOWFALL ALONG THE WRN SPINE
OF THE SRN GREENS MTNS...CNTRL-NRN TACONICS...AND THE BERKSHIRES.
THE LOW TO THE MID LEVEL DEFORMATION ZONE TO THE POTENT UPPER LOW
HAS CONTINUED THE SNOWFALL ALONG THE WRN DACKS...AND WRN-CNTRL MOHAWK
VALLEY.
THE UPSLOPE SNOWFALL IN ERN COLUMBIA...ERN RENSSELAER AND N-CNTRL
BERKSHIRE COUNTIES HAS BEEN IMPRESSIVE THIS AFTERNOON WITH A
REPORT OF 6 INCHES AT PERU IN THE BERKSHIRES AS OF 3 PM. SOME OF
THE KEY FEATURES FOR AN UPSLOPE SUBSYNOPTIC SNOWFALL EVENT WITH A
CLOSED LOW WERE IN PLACE WITH STRONG CYCLONIC VORTICITY
ADVECTION...COLD ADVECTION IN THE LOW LEVELS...MOIST LOW TO MID
LEVELS...AND PERSISTENT W/SW FLOW. USUALLY THIS OCCURS WHEN THE
UPPER LOW IS EAST OR NORTHEAST OF THE REGION PER THE BTV CSTAR
WORK. THIS IS A HYBRID TYPE CASE. THE LATEST FROM THE NAM12 AND
HRRR 3KM REF PRODUCT HAS THE SNOWFALL WINDING DOWN BETWEEN 00Z-
03Z. WE EXPANDED THE ADVISORY TO INCLUDE SRN BERKSHIRE CTY /JUST
NORTH THE MASS PIKE/...AS WELL AS INCLUDING THE NRN-CNTRL TACONICS.
THE SNOW REPORTS HAVE RANGED FROM 1-3 INCHES SO FAR IN
HERKIMER COUNTY AND SW HAMILTON CTY. SOME LAKE MOISTURE WILL
CONTINUE TO BE UTILIZED IN THE DEFORMATION ZONE. OROGRAPHIC
ENHANCEMENT WILL CONTINUE ALONG THE WRN DACKS. WE HAVE EXTENDED
THE WINTER WEATHER ADVISORY FOR THE SRN DACKS AND THE WRN MOHAWK
VALLEY UNTIL MIDNIGHT. BLUSTERY W/SW WINDS WILL PERSIST THIS
EVENING BLOWING THE SNOW AROUND. THE BETTER LIFT AND MOISTURE
CONVERGENCE HAS BEEN CLOSER TO THE LAKE SHORE AND OVER W-CNTRL NY
TODAY. WE PLACED THE HIGHEST SNOW TOTALS THERE OVER NRN HERKIMER
CTY WITH 4 TO 8 INCHES...AND HAVE GONE 3 TO 6 INCHES ELSEWHERE.
LOOKING AT THE BUFKIT SOUNDINGS FROM KSYR...KUCA...AND KRME...THE
INVERSION DOES LOWER TO 4-5 KFT AGL OVERNIGHT WHICH WILL DIMINISH
THE SNOW...AND THE SFC TO BOUNDARY LAYER FLOW BEGINS TO VEER MORE
TO THE NW /CLOSE TO A 300 DEGREE TRAJECTORY/ WITH THE PASSAGE OF
ANOTHER COLD FRONT /THE LEADING EDGE OF ARCTIC AIR/. THERE COULD BE
A QUICK LAKE EXTENSION DOWN THE MOHAWK VALLEY FOR SOME SCT SNOW
SHOWERS TOWARDS DAYBREAK. THE HRRR HINTS AT HIS POSSIBILITY. WE
WILL HAVE TO MONITOR IF THIS MATERIALIZES.
IN TERMS OF THE WIND ADVISORY...GUSTS HAVE GENERALLY BEEN 30-35
KTS...JUST SHORT OF WIND ADVISORY CRITERIA. HOWEVER...AS OF 4 PM
KALB JUST HAD A GUST TO 36 KTS...AND THE H925 WINDS DO INCREASE TO
35-40 KTS...AND THE H850 WINDS TO 50-60 KTS BY 00Z. WE ARE
CONCERNED A FEW GUSTS COULD REACH 40 KTS OR SO..IF WE MIX TO H925. THE
LOW LEVEL PRESSURE GRADIENT WILL BE INCREASING...AND THERE IS A SFC
TROUGH MOVING ACROSS THE REGION AT 21Z PER THE RUC. WE WILL KEEP
THE WIND ADVISORY UP UNTIL MIDNIGHT. THE WINDS WILL GRADUALLY EASE
SLIGHTLY AFTER MIDNIGHT FROM THE W AT 15-25 MPH WITH SOME GUSTS
AROUND 35 MPH.
A BATCH OF SNOW SHOWERS OR SQUALLS WILL MOVE ACROSS THE REGION
BWTN 21Z-00Z. THIS COULD PRODUCE A DUSTING TO A FEW INCHES OF
SNOWFALL IN THE NON-ADVISORY AREAS FROM THE CAPITAL REGION NORTH.
LOWS TONIGHT WILL BE CHILLY WITH 5-10F READINGS OVER THE
ADIRONDACK PARK...TEENS ELSEWHERE..EXCEPT LOWER TO MID 20S FROM
KALB SOUTH DOWN THE HUDSON RIVER VALLEY...AND EAST OF THE GREEN
MTNS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
SATURDAY...ANOTHER BOUNDARY MOVES THROUGH DURING THE MORNING...AS
THE SFC TO BOUNDARY LAYER FLOW CONTINUES TO VEER TO THE NORTHWEST.
THERE MAYBE A FEW MULTIBANDS OFF LAKE ONTARIO MAINLY IMPACTING
CNTRL NY. THE BEST CHC OF ISOLATED TO SCT SNOW SHOWERS AND
FLURRIES WILL BE WEST OF THE HUDSON RIVER VALLEY. THE STRONG
SUBSIDENCE FROM THE ARCTIC HIGH BUILDING IN WILL TEND TO SQUASH ANY
FURTHER DEVELOPMENT OF THE LAKE EFFECT SNOW GETTING INTO MOST OF
THE REGION. ANY ACCUMULATIONS FOR THE WRN MOHAWK VALLEY/ERN
CATSKILLS SHOULD BE LIGHT. OTHERWISE...COLD ADVECTION CONTINUES
OVER THE REGION WITH H850 TEMPS FALLING TO -15C TO -20C. MAX
TEMPS WILL OCCUR EARLY TOMORROW WITH HIGHS IN THE 25-30F RANGE
SOUTH AND EAST OF THE CAPITAL REGION...AND MIDS TEENS TO L20S
NORTH AND WEST...EXCEPT OVER THE SRN DACKS...WHERE SOME SINGLE
DIGITS AND LOWER TEENS WILL BE COMMON. IT WILL STILL BE BLUSTERY
WITH WINDCHILLS IN THE SINGLE DIGITS AND TEENS...AND BELOW ZERO
NORTH AND WEST OF THE CAPITAL REGION.
SATURDAY NIGHT...TRICKY FORECAST HOW FAST THE WINDS DECOUPLE WITH
THE ARCTIC HIGH BUILDING IN. WE COULD FLIRT WITH SOME ADVISORY
LEVELS WIND CHILLS OVER THE SRN DACKS...IF WE MAINTAIN WINDS IN
EXCESS OF 5 MPH. WE WILL CONTINUE THE PREVIOUS FORECASTS MENTION
IN THE HWO. OVERALL...A BITTERLY COLD NIGHT IS EXPECTED WITH LOWS
IN THE SINGLE DIGITS FROM THE CAPITAL DISTRICT SOUTH AND
EAST...AND ZERO TO 10 BELOW NORTH AND WEST...EXCEPT 10-20 BELOW IN
THE SRN DACKS.
SUNDAY-SUNDAY NIGHT...ARCTIC HIGH PRESSURE BUILDS OVER NY AND NEW
ENGLAND ON SUNDAY. MOSTLY SUNNY AND COLD CONDITIONS WILL PREVAIL
WITH HIGHS IN THE TEENS TO L20S OVER MOST OF THE REGION...EXCEPT
SOME SINGLE DIGITS OVER THE SRN DACKS...AND THE SRN GREENS. WE
START TO WARM ADVECT SUNDAY NIGHT...AS THE HIGH SLOWLY SHIFTS
DOWNSTREAM OVER NRN NEW ENGLAND. SOME CIRRUS MAY CREEP IN AHEAD OF
A WARM FRONT OVER THE GREAT LAKES REGION...AND SE ONTARIO. LOWS
WILL NOT BE AS COLD WITH MAINLY SINGLE DIGITS FROM THE MOHAWK
VALLEY...CAPITAL REGION SOUTH...AND SOME ZERO TO 10 BELOW READINGS
NORTH.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
A TRANQUIL WEATHER PATTERN ON MONDAY WILL TRANSITION TO A MORE
ACTIVE PATTERN TOWARD THE END OF THE WORK WEEK. A RIDGE LOOKS TO BE
IN PLACE MONDAY MORNING BUT AS THE DAY PROGRESSES...A SHORTWAVE
TROUGH IN THE MIDWEST WILL ACT TO SHIFT THE RIDGE FROM NORTHEAST
INTO THE ATLANTIC COAST. THIS SHORTWAVE WILL PROGRESS TO THE EAST
TOWARD EASTERN OHIO/W PA LATE TUESDAY INTO EARLY WEDNESDAY. THIS LOW
WILL PRODUCE WINDY CONDITIONS WITH SUSTAINED WNW WINDS AT 15-20 KTS
AND GUSTS 20-25 KTS THROUGH LATE WEDNESDAY.
THE ECMWF AND GFS BOTH SHOW THE POSITIVE TILTED TROUGH BECOMING A
NEGATIVE TROUGH OVER THE OHIO VALLEY WEDNESDAY MORNING...WITH
CYCLOGENESIS AT THE SFC OVER THE GREAT LAKES AREA AT THIS TIME. THE
MODELS AT THIS TIME SHOWS A DECENT LOW PRESSURE SYSTEM OVER THE
LAKES AND WESTERN NY MOVING NORTHEAST ALONG THE NY/CANADA BORDER. AT
THIS TIME...MODEL FORECAST SOUNDINGS SHOW THE PRECIPITATION TYPE
OVER THE FA STARTING OUT AS SNOW. BUT WITH TEMPERATURES WARMING
THROUGHOUT THE DAY...AREAS IN THE IMMEDIATE CAPITAL REGION AND SOUTH
WILL LIKELY CHANGE TO RAIN. AREAS NORTH OF ALB WILL SEE SNOW OR A
WINTRY MIX...DEPENDING ON ELEVATION.
THE GFS MODEL HAS THE SFC LOW PRESSURE SYSTEM MOVING OUT OF THE
NORTHEAST MOVING FASTER BUT ALL OF THE MODELS HAVE THE LOW PRESSURE
SYSTEMS OUT OF THE REGION BY LATE WEDNESDAY. THIS WILL BE FOLLOWED
BY ANOTHER SYSTEM...BUT MODELS LACKING CONSENSUS FOR LATE THURSDAY
INTO FRIDAY. GFS SHOWING NEGATIVELY TILTED UPPER LEVEL TROUGH WHICH
DEVELOPS A COASTAL LOW OFF OF CAPE COD. MEANWHILE THE ECMWF SHOW THE
UPPER LEVEL TROUGH HANGING BACK WEST...THEN RETREATING UP INTO
CANADA. WILL HAVE TO KEEP AN EYE AS THIS SYSTEM DEVELOPS.
NEAR NORMAL MAX TEMPS WILL WARM ON TUESDAY FROM A WARM FRONT AHEAD
OF THE APPROACHING LOW...TO 10 DEGREES ABOVE NORMAL. THIS WILL BE
FOLLOWED BY A COLD FRONT ON TUESDAY AND A STRONG NW FLOW PRODUCING
SLIGHTLY BELOW NORMAL TEMPERATURES THROUGH THE REST OF THE PERIOD.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
A STRENGTHENING LOW PRESSURE SYSTEM NEAR MONTREAL IS BRINGING VERY
WINDY AND MUCH COLDER AIR TO THE REGION THIS AFTERNOON...WITH
SCATTERED TO NUMEROUS SNOW SHOWERS EXPECTED...ESP AT KGFL AND KALB.
BOTH VSBYS AND CIGS COULD BECOME IFR IN ANY SNOW SHOWERS OR EMBEDDED
HEAVIER SQUALLS THIS AFTERNOON. CIGS AT KGFL AND KALB WILL LIKELY
REMAIN MVFR THIS EVENING AS COLD CYCLONIC FLOW CONTINUES. SCATTERED
SNOW SHOWERS WILL CONTINUE OVERNIGHT AS WELL ALTHOUGH THE BEST
CHANCE FOR STEADY SNOW IS THIS AFTERNOON AND EVENING. THE SNOW
SHOWERS SHOULD BECOME LESS NUMEROUS OVERNIGHT...ALTHOUGH MAY LINGER
AT KALB THROUGH DAYBREAK SATURDAY.
WINDS WILL BE WESTERLY AT 15-25 KT...WITH SOME STRONGER GUSTS
POSSIBLE...WINDS WILL REMAIN STRONG/GUSTY THROUGH THIS
EVENING...BEFORE DIMINISHING SLIGHTLY LATER THIS EVENING...ESP AT
KPOU.
OUTLOOK...
FRI NT...MAINLY MVFR...WINDY. SCATTERED -SHSN.
SAT-MON...VFR...NO SIG WX.
MON NT-TUE...MVFR...CHC IFR -SHSN/-FZRA.
WED...VFR. NO SIG WX.
&&
.HYDROLOGY...
NO MAJOR PROBLEMS ARE EXPECTED ON THE MAIN STEM RIVERS OVER THE
NEXT 5 DAYS. THE ARCTIC AIR MASS WILL ALLOW ICE TO FORM AND CONTINUE TO
THICKEN ON MAIN STEM RIVERS...LAKES...AND OTHER BODIES OF WATER
THROUGH THE WEEKEND. TEMPERATURES WILL MODERATE BACK ABOVE NORMAL
BY TUESDAY.
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...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR CTZ001-013.
NY...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ032-033-
038>043-047>054-058>061-063>066-082>084.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ032-
033-038-042-054-061.
MA...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ001-025.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ001-
025.
VT...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VTZ013>015.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VTZ013-
014.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...KGM/LFM
AVIATION...SND
HYDROLOGY...WASULA
AREA FORECAST DISCUSSION
NWS NEW YORK NY
111 PM EST FRI JAN 13 2012
.SYNOPSIS...
LOW PRESSURE WILL TRACK DOWN THE SAINT LAWRENCE THROUGH
TONIGHT...WITH AN ASSOCIATED SECONDARY COLD APPROACHING THE TRI-
STATE LATE TONIGHT...AND PUSHING ACROSS THE AREA SATURDAY. HIGH
PRESSURE BUILDS IN BEHIND THE DEPARTING STORM SYSTEM SATURDAY
THROUGH EARLY NEXT WEEK. ANOTHER STORM SYSTEM AFFECTS THE AREA
MONDAY NIGHT THROUGH TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AT 17Z...A VIGOROUS COLD FRONT WAS LOCATED NEAR THE WESTERN RI/MA
BORDER. PER LATEST WATER VAPOR...JET STREAK HAS PASSED TO THE
EAST...AND 500 HPA RUC ANALYSIS SHOWS NEGATIVE VORTICITY ADVECTION
OVER THE AREA. SO WHILE SOME ISOLD FLURRIES CANNOT BE RULED
OUT...BASICALLY GOING WITH A DRY FORECAST...WITH THE EXCEPTION OF
FAR NW ZONES...WHERE HAVE SLIGHT CHANCE FOR LAKE EFFECT SNOW
SHOWERS THIS AFTERNOON. LITTLE OR NO ACCUMULATION EXPECTED WITH THESE.
WITH RECENT PEAK WIND GUSTS TO 40 KT AT KPHI AND 41 KT AT
KFIG...WILL CONTINUE WIND ADVISORY AS IS FOR NOW...THOUGH APPEARS
POTENTIAL FOR REACHING IS MARGINAL ACROSS INTERIOR ZONES (NOTING
PEAK GUSTS ONLY TO 37 KT AT KMPO).
TEMPERATURES FALLING FAIRLY RAPIDLY BEHIND THE FRONT...WITH HIGHS
FOR TODAY REACHED JUST AHEAD OF THE FRONT THIS MORNING. NAM
2-METER TEMPERATURES ARE HANDLING THIS VERY WELL...AND HAVE BEEN
USED TO UPDATE HOURLY TEMPERATURE GRIDS THIS AFTERNOON. ALL AREAS
SHOULD BE INTO THE 30S BY LATE AFTERNOON...WITH NW PORTIONS OF THE
CWA FALLING INTO THE M-U 20S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
COLD ADVECTION CONTINUES TONIGHT BUT IS WEAKEN THAN DURING EARLY
THIS MORNING. ALSO WINDS ALOFT...900 MB TO 850 MB...DIMINISH
QUICKLY THIS EVENING. WILL CONTINUE TO WIND ADVISORY AS POSTED
THROUGH MIDNIGHT...HOWEVER WINDS COULD FALL BELOW ADVISORY LEVELS
EARLY IN THE EVENING.
UPPER TROUGH REMAINS IN THE AREA TONIGHT THROUGH SATURDAY AS SHORT
WAVES ROTATE THROUGH. CYCLONIC FLOW CONTINUES IN THE AREA AS
SURFACE LOW MOVES SLOWLY TO THE NORTHEAST THROUGH THE PERIOD.
PRECIPITATION IS NOT EXPECTED HOWEVER WITH MOISTURE IN THE AREA
VARYING CLOUDINESS IS EXPECTED.
USED THE NAM GUIDANCE FOR TEMPERATURES THROUGH SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
JET STREAM SOUTH OF THE REGION SIGNALING COLD AIR MASS ENTRENCHED
ACROSS THE AREA WITH A TROUGH INDICATED AT 500 MB. HOWEVER...THIS
WILL BE A PROGRESSIVE PATTERN AS TROUGH AXIS SLIDES THROUGH ON
SUNDAY. SECONDARY COLD FRONT JUST MOVING SOUTH OF REGION SAT NIGHT
WITH HIGH PRESSURE BUILDING IN FROM THE WEST AT THE SURFACE.
NORTHWEST FLOW WILL CONTINUE TO REINFORCE THE COLD AIR ADVECTION.
RIDGING WILL THEN TAKE PLACE SUNDAY NIGHT WITH HEIGHT RISES AS TEMPS
INCREASE AT 850 MB. SFC HIGH PRESSURE CENTERS OVER THE AREA WITH
GOOD RADIATIONAL COOLING CONDITIONS EXPECTED.
FAVORED MET GUIDANCE IN THIS TIME FRAME WITH BELOW NORMAL
TEMPERATURES EXPECTED. LOWS WITH BETTER COLD AIR ADVECTION SAT NIGHT
BUT BREEZY CONDITIONS WILL BE SIMILAR TO SUN NIGHT LOWS WITH THAT
NIGHT HAVING BETTER RADIATIONAL COOLING AS WINDS LIGHTEN WITH THE
DECREASED PRESSURE GRADIENT.
HIGH PRESSURE AND RIDGING MOVES OFFSHORE ON MONDAY WITH A RETURN
SOUTHERLY FLOW DEVELOPING. TEMPERATURES MONDAY AND MONDAY NIGHT
SHOULD BE NEAR NORMAL LEVELS. FORECAST FAVORED THE GFS NEAR THIS
TIME FRAME. KEPT A SMALLER SPREAD OF TEMPERATURES MONDAY NIGHT AND
SLIGHTLY WARMER NEAR THE COAST WITH THE SOUTHERLY FLOW.
THERE WILL BE AN INCREASING CHANCE OF PRECIP WITH AN ADVANCING COLD
FRONT ACCOMPANYING ALOFT BY A POSITIVELY TILTED DIGGING TROUGH WEST
OF THE APPALACHIANS. INCREASED POPS NEAR 50 PERCENT HERE AS DECENT
QUASI-GEOSTROPHIC FORCING SHOWN BY MODELS WITH Q VECTOR CONVERGENCE
BETWEEN 850 AND 500 MB. COULD BE A COMPLEX WINTER WX SCENARIO
SHAPING UP FOR THE INTERIOR AS THE WARMER AIR ALOFT AT 850 MB
INCREASES NEAR TO A FEW DEGREES ABOVE FREEZING. WITH INTERIOR
TEMPS STILL AT OR BELOW FREEZING AND NOT AS INFLUENCED BY THE
SOUTHERLY FLOW...A PERIOD OF FROZEN PRECIP CONSISTING OF
SNOW...SLEET...AND/OR FREEZING RAIN WOULD BE POSSIBLE. KEPT
LOCATIONS NEAR THE COAST TO JUST PLAIN RAIN WITH THE SOUTHERLY
FLOW.
WARM AIR EVENTUALLY SPREADS ACROSS ENTIRE FORECAST REGION BY LATER
TUESDAY MORNING AND ALLOWS FOR PRECIP TO BE MAINLY RAIN THEREAFTER.
THE COLD FRONT PUSHES THROUGH BY LATE TUESDAY NIGHT WITH A LOWERED
TREND TO RAIN SHOWERS WHICH COULD MIX WITH AND CHANCE TO SNOW
SHOWERS ESPECIALLY FARTHER INLAND AT THE TAIL END OF THE PRECIP
RIGHT BEHIND THE COLD FRONT. WITH COLDER AIR COMING INTO PLACE AS
WELL ALOFT...THIS MAKES FOR A MORE SIMPLE SCENARIO OF A MIX OF RAIN
AND SNOW SHOWERS.
KEPT SLIGHT CHANCE POPS FOR SNOW AND RAIN SHOWERS ON WEDNESDAY AND
THURSDAY BECAUSE BEHIND THE COLD FRONT A BROAD UPPER LEVEL TROUGH
HANGS ON IN THE AREA WITH AN EMBEDDED SHORTWAVE/VORTICITY MAXIMUM
PUSHING THROUGH LATER ON WEDNESDAY AS WELL AS THURSDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
HIGH PRESSURE SLOWLY BUILDS IN THIS AFTERNOON.
VFR...HOWEVER BRIEF MVFR CIGS POSSIBLE THIS AFTERNOON.
FOR ALL TERMINALS...THERE IS A CHANCE OF FLURRIES OR BRIEF LIGHT
SNOW SHOWERS NOW THROUGH 21Z-22Z. THIS IS NOT HOWEVER EXPECTED TO
ACCUMULATE ON RUNWAYS OR CAUSE SUB-VFR VISIBILITIES AT GROUND
LEVEL. THE DURATION AND COVERAGE OF THE FLURRIES/SNOW SHOWERS ARE
NOT ENOUGH TO WARRANT INCLUSION AS EVEN IN A TEMPO GROUP.
MEDIUM TO HIGH CONFIDENCE IN WIND DIRECTION. SUSTAINED/GUST
MAGNITUDES MAY BE OFF BY AROUND 5 KT AT TIMES.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: OCCASIONAL GUSTS UP TO 41-44 KTS POSSIBLE
THIS AFTERNOON.
KJFK FCSTER COMMENTS: SUSTAINED WINDS OF 30-33 KT POSSIBLE AT
TIMES UNTIL AROUND 20Z. OCCASIONAL GUSTS UP TO 44-47 KTS POSSIBLE
THIS AFTERNOON.
KLGA FCSTER COMMENTS: OCCASIONAL GUSTS UP TO 39-42 KTS POSSIBLE
THIS AFTERNOON.
KTEB FCSTER COMMENTS: OCCASIONAL GUSTS 36-39 KTS POSSIBLE THROUGH
THIS AFTERNOON.
KHPN FCSTER COMMENTS: SUSTAINED WINDS AND GUSTS FORECAST MAY BE
AROUND 5 KT TOO HIGH THIS AFTERNOON.
KISP FCSTER COMMENTS: OCCASIONAL UP TO 37-40 KTS POSSIBLE THIS
AFTERNOON.
OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
SAT PM...VFR. FLURRIES POSSIBLE EARLY. GUSTY NW-W WINDS 20-25 KT.
SUN-MON...VFR.
TUE...SUB VFR POSSIBLE IN RAIN/MORNING WINTRY PRECIP.
WED...SUB VFR WITH WINTRY MIX POSSIBLE AM. GUSTY NW WINDS 20-25 KT
POSSIBLE.
&&
.MARINE...
GUSTS TO GALE FORCE BEHIND THE EXITING COLD FRONT EXPECTED INTO THIS
EVENING...THOUGH NOT NECESSARILY ALL THE TIME. WILL CONTINUE WITH
GALE WARNING AS AS...WITH GALE WARNING THROUGH THE OVERNIGHT HOURS
ACROSS THE OCEAN WATERS EAST OF FIRE ISLAND INLET.
ONCE THE WINDS DIMINISH ON THE REMAINDER OF THE FORECAST WATERS
THIS EVENING...SMALL CRAFT WIND GUSTS WILL CONTINUE THROUGH MUCH OF
THE OVERNIGHT. AND SMALL CRAFT WINDS WILL BE LIKELY ON THE OCEAN
WATERS INTO SATURDAY AFTERNOON...WITH SEAS REMAINING ABOVE 5 FT INTO
SATURDAY NIGHT.
STRONG OFF SHORE FLOW THROUGH TODAY WILL PUSH WATER OUT OF THE
WESTERN LONG ISLAND SOUND. THIS WILL RESULT IN LOW WATER PROBLEMS
DURING LOW TIDE THIS EVENING AND A LOW WATER ADVISORY HAS BEEN
ISSUED.
MARGINAL SCA WIND GUSTS REMAINING ON THE OUTER OCEAN WATERS THROUGH
SAT NIGHT BEFORE ENDING SUN MORNING. SUB SCA CONDITIONS THEN
EXPECTED THROUGH MON. MON NIGHT...OUT AHEAD OF NEXT COLD
FRONT...SOUTHERLY FLOW WILL LEAD TO A RETURN OF WIND GUSTS AND SEAS
TO SCA LEVELS WHICH COULD VERY WELL CONTINUE THROUGH THE REMAINDER
OF THE FORECAST.
&&
.HYDROLOGY...
AROUND A TENTH OF AN INCH OF RAINFALL IS POSSIBLE THROUGH EARLY THIS
AFTERNOON. DRY WEATHER RETURNS TONIGHT AND CONTINUES THROUGH MONDAY.
&&
.TIDES/COASTAL FLOODING...
STRONG AND GUSTY SOUTHWESTERLY WINDS DEVELOPING THIS MORNING AND
CONTINUING THROUGH THE DAY WILL PUSH WATER OUT OF THE WESTERN LONG
ISLAND SOUND. BY THE TIME OF THE LOW TIDE EARLY THIS EVENING TIDAL
DEPARTURES ARE EXPECTED TO RUN 3 TO 3 1/2 FT BELOW NORMAL. THIS
WILL RESULT IN LOW WATER PROBLEMS AND A LOW WATER ADVISORY HAS
BEEN ISSUED.
LATEST TRENDS IN OBSERVATIONS BEGINNING TO GIVE CONCERN ABOUT LOW
WATER IN NEW YORK HARBOR AND THE SOUTH SHORE BAYS AS WELL FOR
SATURDAY MORNINGS LOW TIDE. WILL CONTINUE TO EVALUATE.
&&
.EQUIPMENT...
THE KOKX WSR-88D WILL BE DOWN FOR THE INSTALLATION OF DUAL
POLARIZATION SOFTWARE AND HARDWARE THROUGH JANUARY 24TH.
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR CTZ005>012.
NY...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ067>075-
078>081-176>179.
NJ...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NJZ002-004-006-
103>108.
MARINE...GALE WARNING UNTIL MIDNIGHT EST TONIGHT FOR ANZ330-335-338-340-
345-355.
LOW WATER ADVISORY FROM 6 PM TO 11 PM EST THIS EVENING FOR
ANZ335.
GALE WARNING UNTIL 5 AM EST SATURDAY FOR ANZ350-353.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR CTZ005>012.
NY...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ067>075-
078>081-176>179.
NJ...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NJZ002-004-006-
103>108.
MARINE...GALE WARNING UNTIL MIDNIGHT EST TONIGHT FOR ANZ330-335-338-340-
345-355.
LOW WATER ADVISORY FROM 6 PM TO 11 PM EST THIS EVENING FOR
ANZ335.
GALE WARNING UNTIL 5 AM EST SATURDAY FOR ANZ350-353.
&&
$$
AVIATION...JC
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1218 PM EST FRI JAN 13 2012
.SYNOPSIS...
LOW PRESSURE WILL TRACK DOWN THE SAINT LAWRENCE THROUGH
TONIGHT...WITH AN ASSOCIATED SECONDARY COLD APPROACHING THE TRI-
STATE LATE TONIGHT...AND PUSHING ACROSS THE AREA SATURDAY. HIGH
PRESSURE BUILDS IN BEHIND THE DEPARTING STORM SYSTEM SATURDAY
THROUGH EARLY NEXT WEEK. ANOTHER STORM SYSTEM AFFECTS THE AREA
MONDAY NIGHT THROUGH TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AT 17Z...A VIGOROUS COLD FRONT WAS LOCATED NEAR THE WESTERN RI/MA
BORDER. PER LATEST WATER VAPOR...JET STREAK HAS PASSED TO THE
EAST...AND 500 HPA RUC ANALYSIS SHOWS NEGATIVE VORTICITY ADVECTION
OVER THE AREA. SO WHILE SOME ISOLD FLURRIES CANNOT BE RULED
OUT...BASICALLY GOING WITH A DRY FORECAST...WITH THE EXCEPTION OF
FAR NW ZONES...WHERE HAVE SLIGHT CHANCE FOR LAKE EFFECT SNOW
SHOWERS THIS AFTERNOON. LITTLE OR NO ACCUMULATION EXPECTED WITH THESE.
WITH RECENT PEAK WIND GUSTS TO 40 KT AT KPHI AND 41 KT AT
KFIG...WILL CONTINUE WIND ADVISORY AS IS FOR NOW...THOUGH APPEARS
POTENTIAL FOR REACHING IS MARGINAL ACROSS INTERIOR ZONES (NOTING
PEAK GUSTS ONLY TO 37 KT AT KMPO).
TEMPERATURES FALLING FAIRLY RAPIDLY BEHIND THE FRONT...WITH HIGHS
FOR TODAY REACHED JUST AHEAD OF THE FRONT THIS MORNING. NAM
2-METER TEMPERATURES ARE HANDLING THIS VERY WELL...AND HAVE BEEN
USED TO UPDATE HOURLY TEMPERATURE GRIDS THIS AFTERNOON. ALL AREAS
SHOULD BE INTO THE 30S BY LATE AFTERNOON...WITH NW PORTIONS OF THE
CWA FALLING INTO THE M-U 20S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
COLD ADVECTION CONTINUES TONIGHT BUT IS WEAKEN THAN DURING EARLY
THIS MORNING. ALSO WINDS ALOFT...900 MB TO 850 MB...DIMINISH
QUICKLY THIS EVENING. WILL CONTINUE TO WIND ADVISORY AS POSTED
THROUGH MIDNIGHT...HOWEVER WINDS COULD FALL BELOW ADVISORY LEVELS
EARLY IN THE EVENING.
UPPER TROUGH REMAINS IN THE AREA TONIGHT THROUGH SATURDAY AS SHORT
WAVES ROTATE THROUGH. CYCLONIC FLOW CONTINUES IN THE AREA AS
SURFACE LOW MOVES SLOWLY TO THE NORTHEAST THROUGH THE PERIOD.
PRECIPITATION IS NOT EXPECTED HOWEVER WITH MOISTURE IN THE AREA
VARYING CLOUDINESS IS EXPECTED.
USED THE NAM GUIDANCE FOR TEMPERATURES THROUGH SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
JET STREAM SOUTH OF THE REGION SIGNALING COLD AIR MASS ENTRENCHED
ACROSS THE AREA WITH A TROUGH INDICATED AT 500 MB. HOWEVER...THIS
WILL BE A PROGRESSIVE PATTERN AS TROUGH AXIS SLIDES THROUGH ON
SUNDAY. SECONDARY COLD FRONT JUST MOVING SOUTH OF REGION SAT NIGHT
WITH HIGH PRESSURE BUILDING IN FROM THE WEST AT THE SURFACE.
NORTHWEST FLOW WILL CONTINUE TO REINFORCE THE COLD AIR ADVECTION.
RIDGING WILL THEN TAKE PLACE SUNDAY NIGHT WITH HEIGHT RISES AS TEMPS
INCREASE AT 850 MB. SFC HIGH PRESSURE CENTERS OVER THE AREA WITH
GOOD RADIATIONAL COOLING CONDITIONS EXPECTED.
FAVORED MET GUIDANCE IN THIS TIME FRAME WITH BELOW NORMAL
TEMPERATURES EXPECTED. LOWS WITH BETTER COLD AIR ADVECTION SAT NIGHT
BUT BREEZY CONDITIONS WILL BE SIMILAR TO SUN NIGHT LOWS WITH THAT
NIGHT HAVING BETTER RADIATIONAL COOLING AS WINDS LIGHTEN WITH THE
DECREASED PRESSURE GRADIENT.
HIGH PRESSURE AND RIDGING MOVES OFFSHORE ON MONDAY WITH A RETURN
SOUTHERLY FLOW DEVELOPING. TEMPERATURES MONDAY AND MONDAY NIGHT
SHOULD BE NEAR NORMAL LEVELS. FORECAST FAVORED THE GFS NEAR THIS
TIME FRAME. KEPT A SMALLER SPREAD OF TEMPERATURES MONDAY NIGHT AND
SLIGHTLY WARMER NEAR THE COAST WITH THE SOUTHERLY FLOW.
THERE WILL BE AN INCREASING CHANCE OF PRECIP WITH AN ADVANCING COLD
FRONT ACCOMPANYING ALOFT BY A POSITIVELY TILTED DIGGING TROUGH WEST
OF THE APPALACHIANS. INCREASED POPS NEAR 50 PERCENT HERE AS DECENT
QUASI-GEOSTROPHIC FORCING SHOWN BY MODELS WITH Q VECTOR CONVERGENCE
BETWEEN 850 AND 500 MB. COULD BE A COMPLEX WINTER WX SCENARIO
SHAPING UP FOR THE INTERIOR AS THE WARMER AIR ALOFT AT 850 MB
INCREASES NEAR TO A FEW DEGREES ABOVE FREEZING. WITH INTERIOR
TEMPS STILL AT OR BELOW FREEZING AND NOT AS INFLUENCED BY THE
SOUTHERLY FLOW...A PERIOD OF FROZEN PRECIP CONSISTING OF
SNOW...SLEET...AND/OR FREEZING RAIN WOULD BE POSSIBLE. KEPT
LOCATIONS NEAR THE COAST TO JUST PLAIN RAIN WITH THE SOUTHERLY
FLOW.
WARM AIR EVENTUALLY SPREADS ACROSS ENTIRE FORECAST REGION BY LATER
TUESDAY MORNING AND ALLOWS FOR PRECIP TO BE MAINLY RAIN THEREAFTER.
THE COLD FRONT PUSHES THROUGH BY LATE TUESDAY NIGHT WITH A LOWERED
TREND TO RAIN SHOWERS WHICH COULD MIX WITH AND CHANCE TO SNOW
SHOWERS ESPECIALLY FARTHER INLAND AT THE TAIL END OF THE PRECIP
RIGHT BEHIND THE COLD FRONT. WITH COLDER AIR COMING INTO PLACE AS
WELL ALOFT...THIS MAKES FOR A MORE SIMPLE SCENARIO OF A MIX OF RAIN
AND SNOW SHOWERS.
KEPT SLIGHT CHANCE POPS FOR SNOW AND RAIN SHOWERS ON WEDNESDAY AND
THURSDAY BECAUSE BEHIND THE COLD FRONT A BROAD UPPER LEVEL TROUGH
HANGS ON IN THE AREA WITH AN EMBEDDED SHORTWAVE/VORTICITY MAXIMUM
PUSHING THROUGH LATER ON WEDNESDAY AS WELL AS THURSDAY.
&&
.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE SLOWLY BUILDS IN BEHIND A COLD FRONT OFF TO THE EAST.
VFR...HOWEVER BRIEF MVFR POSSIBLE UNTIL NOON. COULD BE BRIEF MVFR
CIGS THIS AFTERNOON AS WELL...BUT NOT ENOUGH CONFIDENCE TO PUT
INTO TAFS AT THIS TIME.
IN GENERAL...FORECAST SUSTAINED AND GUSTS MAY BE OFF BY AROUND 5
KT THROUGH THE DAY. MODERATE TO HIGH CONFIDENCE IN WIND DIRECTION.
BATCH OF PRECIP THAT IS NOW JUST EAST OF THE CITY TERMINALS MAY
END WITH A MIX OF RAIN/SLEET/SNOW...BUT THE DURATION OF ANY MIXED
PRECIP IS EXPECTED TO BE VERY BRIEF.
FLURRIES ALSO POSSIBLE AT TIMES THIS AFTERNOON...BUT NOT ENOUGH
CONFIDENCE IN PLACEMENT AND OCCURRENCE TO INCLUDE IN TAFS.
THE STRONG WINDS WILL PERSIST THROUGH AT LEAST 00Z.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KEWR FCSTER COMMENTS: OCCASIONAL GUSTS AROUND 40 KTS POSSIBLE
THROUGH THE REST OF THE MORNING...AND UP TO 41-44 KTS POSSIBLE
THIS AFTERNOON.
KJFK FCSTER COMMENTS: OCCASIONAL GUSTS UP TO 45 KTS POSSIBLE FOR
THE REST OF THIS MORNING...AND UP TO 45-48 KTS POSSIBLE THIS
AFTERNOON.
KLGA FCSTER COMMENTS: OCCASIONAL GUSTS AROUND 40 KTS POSSIBLE
THROUGH THE REST OF THE MORNING...AND UP TO 43-46 KTS POSSIBLE
THIS AFTERNOON.
KTEB FCSTER COMMENTS: OCCASIONAL GUSTS 35-38 KTS POSSIBLE THROUGH THE
REST OF THE MORNING
KHPN FCSTER COMMENTS: GUSTS MIGHT NOT REACH 40 KT THIS AFTERNOON.
KISP FCSTER COMMENTS: OCCASIONAL GUSTS 35-38 KTS POSSIBLE
THROUGH THE REST OF THE MORNING...AND UP TO 40-43 KTS POSSIBLE
THIS AFTERNOON.
OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY...
SAT...VFR. FLURRIES POSSIBLE. GUSTY NW-W WINDS.
SUN-MON...VFR.
TUE...SUB VFR POSSIBLE IN RAIN/MORNING WINTRY PRECIP.
&&
.MARINE...
GUSTS TO GALE FORCE BEHIND THE EXITING COLD FRONT EXPECTED INTO THIS
EVENING...THOUGH NOT NECESSARILY ALL THE TIME. WILL CONTINUE WITH
GALE WARNING AS AS...WITH GALE WARNING THROUGH THE OVERNIGHT HOURS
ACROSS THE OCEAN WATERS EAST OF FIRE ISLAND INLET.
ONCE THE WINDS DIMINISH ON THE REMAINDER OF THE FORECAST WATERS
THIS EVENING...SMALL CRAFT WIND GUSTS WILL CONTINUE THROUGH MUCH OF
THE OVERNIGHT. AND SMALL CRAFT WINDS WILL BE LIKELY ON THE OCEAN
WATERS INTO SATURDAY AFTERNOON...WITH SEAS REMAINING ABOVE 5 FT INTO
SATURDAY NIGHT.
STRONG OFF SHORE FLOW THROUGH TODAY WILL PUSH WATER OUT OF THE
WESTERN LONG ISLAND SOUND. THIS WILL RESULT IN LOW WATER PROBLEMS
DURING LOW TIDE THIS EVENING AND A LOW WATER ADVISORY HAS BEEN
ISSUED.
MARGINAL SCA WIND GUSTS REMAINING ON THE OUTER OCEAN WATERS THROUGH
SAT NIGHT BEFORE ENDING SUN MORNING. SUB SCA CONDITIONS THEN
EXPECTED THROUGH MON. MON NIGHT...OUT AHEAD OF NEXT COLD
FRONT...SOUTHERLY FLOW WILL LEAD TO A RETURN OF WIND GUSTS AND SEAS
TO SCA LEVELS WHICH COULD VERY WELL CONTINUE THROUGH THE REMAINDER
OF THE FORECAST.
&&
.HYDROLOGY...
AROUND A TENTH OF AN INCH OF RAINFALL IS POSSIBLE THROUGH EARLY THIS
AFTERNOON. DRY WEATHER RETURNS TONIGHT AND CONTINUES THROUGH MONDAY.
&&
.TIDES/COASTAL FLOODING...
STRONG AND GUSTY SOUTHWESTERLY WINDS DEVELOPING THIS MORNING AND
CONTINUING THROUGH THE DAY WILL PUSH WATER OUT OF THE WESTERN LONG
ISLAND SOUND. BY THE TIME OF THE LOW TIDE EARLY THIS EVENING TIDAL
DEPARTURES ARE EXPECTED TO RUN 3 TO 3 1/2 FT BELOW NORMAL. THIS
WILL RESULT IN LOW WATER PROBLEMS AND A LOW WATER ADVISORY HAS
BEEN ISSUED.
LATEST TRENDS IN OBSERVATIONS BEGINNING TO GIVE CONCERN ABOUT LOW
WATER IN NEW YORK HARBOR AND THE SOUTH SHORE BAYS AS WELL FOR
SATURDAY MORNINGS LOW TIDE. WILL CONTINUE TO EVALUATE.
&&
.EQUIPMENT...
THE KOKX WSR-88D WILL BE DOWN FOR THE INSTALLATION OF DUAL
POLARIZATION SOFTWARE AND HARDWARE THROUGH JANUARY 24TH.
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR CTZ005>012.
NY...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ067>075-
078>081-176>179.
NJ...WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NJZ002-004-006-
103>108.
MARINE...GALE WARNING UNTIL MIDNIGHT EST TONIGHT FOR ANZ330-335-338-340-
345-355.
LOW WATER ADVISORY FROM 6 PM TO 11 PM EST THIS EVENING FOR
ANZ335.
GALE WARNING UNTIL 5 AM EST SATURDAY FOR ANZ350-353.
&&
$$
SYNOPSIS...MALOIT/MET
NEAR TERM...MALOIT
SHORT TERM...MET
LONG TERM...JM
AVIATION...JMC
MARINE...MALOIT/JM/MET
HYDROLOGY...MET
TIDES/COASTAL FLOODING...MET/MALOIT
EQUIPMENT...MALOIT
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
635 AM EST FRI Jan 13 2012
...Updated for 12Z Aviation Update...
.SYNOPSIS...
08Z water vapor and H4 RUC analysis shows an amplified upper level
pattern across the CONUS this morning. Main feature is longwave
troughing covering much of the county to the east of the continental
divide. Within this larger trough we find a closed upper low
spinning over the Ohio Valley and responsible for plenty of ongoing
winter precipitation from the Great Lakes to the NE states. The base
of this trough extends down to the northern Gulf coast and will
pivot across our region this morning. Early morning satellite
imagery shows areas of high level cirrus streaming across our skies
ahead of the trough axis and associated with upper level jet energy
aligned along the northern Gulf Coast.
At the surface,
Cold front which crossed the forecast area on Thursday continues to
move south and east over the FL peninsula. In the wake of this
front, a ridge of high pressure is building eastward along the Gulf
coast delivering a cooler and drier airmass. Temperatures will
continue a slow slide downward through the pre-dawn hours reaching
the lower/middle 30s by sunrise to the NW of a PC to Tallahassee to
Valdosta line, and upper 30s to low 40s further south and east.
&&
.SHORT TERM (TODAY THROUGH SUNDAY)...
Today,
High pressure centered over Texas will continue to ridge eastward to
our region through the day. The ridge will supply us with a fair,
dry, and cool forecast to end the work week. Will call it mostly
sunny, however there will be some passing cirrus this morning across
the Big Bend zones, and then additional cirrus arriving from the
west late in the day ahead of yet another mid-level shortwave. With
CAA ongoing this morning, temperatures will be slow to respond.
850mb temps will be lowering through the day, with the 0C line
dipping down close to KDHN and KABY. With this cooler low level
airmass in place, expecting high temperatures by mid afternoon to
generally reach the lower 50s (middle 50s down toward KCTY).
Tonight,
Gradient will weaken as the ridge axis continue to build closer to
the region. In terms of a radiational cooling setup, the high
position is certainly not ideal, however it isn`t terrible either.
It is likely that de-coupling of the boundary layer will eventually
take place, although it may take much of the night to occur. With
this in mind, do not anticipate much in the way of hard freeze
conditions, however much of the forecast area will experience
sub-freezing temperatures during the late night hours. Normally
colder locations under radiational cooling will briefly drop down
into the middle 20s around sunrise, with most other spots bottoming
out in the upper 20s to lower 30s.
Saturday/Sunday,
After the cold start Saturday morning, high pressure building
overhead will provide the region with a dry and seasonable weekend.
Airmass will begin to recover during Saturday as the longwave
mid-level trough begins to pull away to the NE. High temperatures
will respond, reaching the upper 50s for afternoon highs. The
overall airmass will not be as cool Saturday night, however the
surface high will be almost directly over the forecast area. This
more favorable high position combined with plenty of residual dry
air will allow for a good radiational cooling setup. Expecting
widespread low temperatures by sunrise to reside between 30-35
degrees. Normally colder spots...especially along the I-10 corridor
and Suwannee River Valley will have the potential to briefly reach
the upper 20s. Temperatures rebound further on Sunday after the cold
start, with 850mb temps climbing to 6-8C by the end of the day. With
the high position in close proximity, overall diurnal mixing will be
held in check, but should still be able to mix out our afternoon
temps into the lower/mid 60s.
&&
.LONG TERM (MONDAY THROUGH NEXT FRIDAY)...
The large scale longwave pattern commences fairly amplified. This is
highlighted in the Nrn stream by weak troughing across Wrn states
and extreme Wrn Atlc and ridging in between. Srn stream with weak
troughing Pac Coast to TX and ridging Ewd into extreme Wrn Atlc. At
surface, high along NC/VA coast with ridge axis swwd into
Apalachee Bay. Low in Canada N of MN with cold front Swwd into
Colorado. This place local area in very dry pattern.
During the rest of the period, Wrn upper trough digs Ewd while Srn
stream upper ridge moves offshore with Srn flow becoming nearly
zonal and stays so before weak troughing approaches shifting flow to
SWLY on Fri. At surface, Ewd moving UPR Nrn trough pushes surface
low moves to Srn Great Lakes kicking high into Atlc. Assocd cold
front dragged rapidly Sewd with deep sly flow setup from Gulf. Front
pushed thru CWA Tues night exiting Wed morn Ern zones bringing sct
shwrs and isold tstms Tues into Wed. In its wake strong high builds
SEWD from Srn Plains Ewd spreading a reinforcing shot of cold and
very dry air across local region Wed into Fri. By end of period high
pushed offshore with next low moving newd into TN valley dragging
trailing cold front to Wrn Gulf. In response, onshore flow with
increasing chances of rain commences again across local area by end
of Fri.
Forecast will show Sct pops Tues aftn into Wed. Otherwise nil pops
thru period. Ahead of the front min temps will be around 10 degrees
above climo Mon and Tues nights dropping to at or below climo Wed
and Thurs nights and may reach freezing in coldest locales. Max
temps commence at least 10 degrees above climo on Tues dropping to
at or below climo on Wed then inching up to a few degrees above
climo by Fri. Average inland min/max temps are 39/62.
&&
.MARINE
A ridge of high pressure will begin to build over the forecast
waters today in the wake of a cold front. Advisory level northwest
winds will diminish through the day, and expect the current advisory
to be dropped later this morning or early this afternoon. After a
round of cautionary level winds tonight, high pressure will build
overhead for much of the weekend keeping winds and seas below
headline criteria. Winds will begin to pick up once again out of the
east and southeast early next week as the ridge of high pressure
exits the region.
&&
.AVIATION (THROUGH 12Z SATURDAY)...
VFR conditions will prevail through the TAF period with only
periodic bands of high level cirrus crossing the sky. Winds have
calmed early this morning from the gusty conditions on Thursday,
however do expect NW/W gusts to pick back up later this morning into
the afternoon. The highest gusts will around around KDHN and KABY
with speeds approaching 20 knots will be possible. Further south for
KECP, KTLH, and KVLD gusts closer to 15 knots should be expected.
These winds will rapidly diminish toward sunset this evening.
&&
.FIRE WEATHER...
A very dry airmass will settle in across the region through
Saturday, with RH values dropping into the lower 20s each afternoon.
Durations of critical RH will be right around 4 hours across SE
AL/SW GA for both days with driest values across SE ALA and SW GA. A
Red Flag warning has been issued for the SE ALA/GA counties for this
afternoon. Altho critical RH values will be realized over N FL,
neither ERC, winds or dispersion red flag values will be realized so
no warning was issued. Similar conditions are expected on Saturday
and a fire weather watch remains in effect for the GA/AL counties.
The airmass will slowly moisten Sun thru Tues then dry out again on
Wed into Thurs in the wake of a cold front.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 52 27 58 29 65 / 0 0 0 0 0
Panama City 53 34 59 38 63 / 0 0 0 0 0
Dothan 51 29 59 33 62 / 0 0 0 0 0
Albany 51 27 58 31 61 / 0 0 0 0 0
Valdosta 52 27 57 31 61 / 0 0 0 0 0
Cross City 56 27 59 30 65 / 0 0 0 0 0
Apalachicola 52 35 57 34 63 / 0 0 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...Red Flag Warning from Noon today to 4 PM CST this afternoon for
Coffee-Dale-Geneva-Henry-Houston.
Fire Weather Watch Saturday afternoon for Coffee-Dale-Geneva-
Henry-Houston.
GA...Red Flag Warning from 1 PM to 5 PM EST this afternoon for Baker-
Ben Hill-Berrien-Brooks-Calhoun-Clay-Colquitt-Cook-Decatur-
Dougherty-Early-Grady-Irwin-Lanier-Lee-Lowndes-Miller-
Mitchell-Quitman-Randolph-Seminole-Terrell-Thomas-Tift-
Turner-Worth.
Fire Weather Watch Saturday afternoon for Baker-Ben
Hill-Berrien-Brooks-Calhoun-Clay-Colquitt-Cook-Decatur-
Dougherty-Early-Grady-Irwin-Lanier-Lee-Lowndes-Miller-
Mitchell-Quitman-Randolph-Seminole-Terrell-Thomas-Tift-
Turner-Worth.
FL...None.
GM...Small Craft Advisory until Noon EST today for Apalachee Bay-
Coastal waters From Ochlockonee River to Apalachicola FL
out to 20 NM-Coastal waters from Suwannee River to Keaton
Beach FL out 20 NM-Coastal waters from Apalachicola to
Destin FL out 20 NM-Waters from Suwannee River to
Apalachicola FL from 20 to 60 NM-Waters from Apalachicola
to Destin FL from 20 to 60 NM.
&&
$$
SYNOPSIS/SHORT TERM/MARINE...MROCZKA
LONG TERM/AVIATION/FIRE WX...BLOCK
AREA FORECAST DISCUSSION...UPDATED FOR AVIATION SECTION
NWS TALLAHASSEE FL
508 AM EST FRI Jan 13 2012
.SYNOPSIS...
08Z water vapor and H4 RUC analysis shows an amplified upper level
pattern across the CONUS this morning. Main feature is longwave
troughing covering much of the county to the east of the continental
divide. Within this larger trough we find a closed upper low
spinning over the Ohio Valley and responsible for plenty of ongoing
winter precipitation from the Great Lakes to the NE states. The base
of this trough extends down to the northern Gulf coast and will
pivot across our region this morning. Early morning satellite
imagery shows areas of high level cirrus streaming across our skies
ahead of the trough axis and associated with upper level jet energy
aligned along the northern Gulf Coast.
At the surface,
Cold front which crossed the forecast area on Thursday continues to
move south and east over the FL peninsula. In the wake of this
front, a ridge of high pressure is building eastward along the Gulf
coast delivering a cooler and drier airmass. Temperatures will
continue a slow slide downward through the pre-dawn hours reaching
the lower/middle 30s by sunrise to the NW of a PC to Tallahassee to
Valdosta line, and upper 30s to low 40s further south and east.
&&
.SHORT TERM (TODAY THROUGH SUNDAY)...
Today,
High pressure centered over Texas will continue to ridge eastward to
our region through the day. The ridge will supply us with a fair,
dry, and cool forecast to end the work week. Will call it mostly
sunny, however there will be some passing cirrus this morning across
the Big Bend zones, and then additional cirrus arriving from the
west late in the day ahead of yet another mid-level shortwave. With
CAA ongoing this morning, temperatures will be slow to respond.
850mb temps will be lowering through the day, with the 0C line
dipping down close to KDHN and KABY. With this cooler low level
airmass in place, expecting high temperatures by mid afternoon to
generally reach the lower 50s (middle 50s down toward KCTY).
Tonight,
Gradient will weaken as the ridge axis continue to build closer to
the region. In terms of a radiational cooling setup, the high
position is certainly not ideal, however it isn`t terrible either.
It is likely that de-coupling of the boundary layer will eventually
take place, although it may take much of the night to occur. With
this in mind, do not anticipate much in the way of hard freeze
conditions, however much of the forecast area will experience
sub-freezing temperatures during the late night hours. Normally
colder locations under radiational cooling will briefly drop down
into the middle 20s around sunrise, with most other spots bottoming
out in the upper 20s to lower 30s.
Saturday/Sunday,
After the cold start Saturday morning, high pressure building
overhead will provide the region with a dry and seasonable weekend.
Airmass will begin to recover during Saturday as the longwave
mid-level trough begins to pull away to the NE. High temperatures
will respond, reaching the upper 50s for afternoon highs. The
overall airmass will not be as cool Saturday night, however the
surface high will be almost directly over the forecast area. This
more favorable high position combined with plenty of residual dry
air will allow for a good radiational cooling setup. Expecting
widespread low temperatures by sunrise to reside between 30-35
degrees. Normally colder spots...especially along the I-10 corridor
and Suwannee River Valley will have the potential to briefly reach
the upper 20s. Temperatures rebound further on Sunday after the cold
start, with 850mb temps climbing to 6-8C by the end of the day. With
the high position in close proximity, overall diurnal mixing will be
held in check, but should still be able to mix out our afternoon
temps into the lower/mid 60s.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY).
The large scale longwave pattern commences fairly amplified. This is
highlighted in the Nrn stream by weak troughing across Wrn states
and extreme Wrn Atlc and ridging in between. Srn stream with weak
troughing Pac Coast to TX and ridging Ewd into extreme Wrn Atlc. At
surface, high along NC/VA coast with ridge axis swwd into
Apalachee Bay. Low in Canada N of MN with cold front Swwd into
Colorado. This place local area in very dry pattern.
During the rest of the period, Wrn upper trough digs Ewd while Srn
stream upper ridge moves offshore with Srn flow becoming nearly
zonal and stays so before weak troughing approaches shifting flow to
SWLY on Fri. Second upper trough over Gulf digs rapidly ESE Tuesday
and Tuesday night. At surface, Above troughs push surface low moves
to Srn Great Lakes kicking high into Atlc. Assocd cold front with
limited instability dragged rapidly Sewd with deep sly flow setup
from Gulf. GFS and ECMWF similar in timing and intensity of
front pushed thru CWA Tues night exiting Wed morn Ern most zones
bringing sct shwrs and a few tstms Tues aftn into early Wed. In its
wake, strong high builds SEWD from Srn Plains Ewd spreading a
reinforcing shot of cold and very dry air across local region Wed
into Fri. By end of period high pushed offshore with next low moving
newd into TN valley dragging trailing cold front to Wrn Gulf. In
response, onshore flow with increasing chances of rain commences
again across local area by end of Fri.
Forecast will show Sct pops Tues aftn into Wed. Otherwise nil pops
thru period. Ahead of the front min temps will be around 10 degrees
above climo Mon and Tues nights dropping to at or below climo Wed
and Thurs nights and may reach freezing in coldest locales. Max
temps commence at least 10 degrees above climo on Tues dropping to
at or below climo on Wed then inching up to a few degrees above
climo by Fri. Average inland min/max temps are 39/62.
&&
.AVIATION (THROUGH 12Z SATURDAY)...
Wind speeds will continue to be in the 5 to 10 kt range and locally
gusty coast and ern most counties until around sunrise before
increasing to around 10kts with higher gusts mainly S/Cntrl GA until
it becomes near calm after sunset. Aside from a scattering of low
level clouds, expect only SCT-BKN cirrus to stream over the region
thru 12z Sat.
&&
.MARINE
A ridge of high pressure will begin to build over the forecast
waters today in the wake of a cold front. Advisory level northwest
winds will diminish through the day, and expect the current advisory
to be dropped later this morning or early this afternoon. After a
round of cautionary level winds tonight, high pressure will build
overhead for much of the weekend keeping winds and seas below
headline criteria. Winds will begin to pick up once again out of the
east and southeast early next week as the ridge of high pressure
exits the region.
&&
.FIRE WEATHER...
A very dry airmass will settle in across the region through
Saturday, with RH values dropping into the lower 20s each afternoon.
Durations of critical RH will be right around 4 hours across SE
AL/SW GA for both days with driest values across SE ALA and SW GA. A
Red Flag warning has been issued for the SE ALA/GA counties for this
afternoon. Altho critical RH values will be realized over N FL,
neither ERC, winds or dispersion red flag values will be realized so
no warning was issued. Similar conditions are expected on Saturday
and a fire weather watch remains in effect for the GA/AL counties.
The airmass will slowly moisten Sun thru Tues then dry out again on
Wed into Thurs in the wake of a cold front.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 52 27 58 29 65 / 0 0 0 0 0
Panama City 53 34 59 38 63 / 0 0 0 0 0
Dothan 51 29 59 33 62 / 0 0 0 0 0
Albany 51 27 58 31 61 / 0 0 0 0 0
Valdosta 52 27 57 31 61 / 0 0 0 0 0
Cross City 56 27 59 30 65 / 0 0 0 0 0
Apalachicola 52 35 57 34 63 / 0 0 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...Red Flag Warning from Noon today to 4 PM CST this afternoon for
Coffee-Dale-Geneva-Henry-Houston.
Fire Weather Watch Saturday afternoon for Coffee-Dale-Geneva-
Henry-Houston.
GA...Red Flag Warning from 1 PM to 5 PM EST this afternoon for Baker-
Ben Hill-Berrien-Brooks-Calhoun-Clay-Colquitt-Cook-Decatur-
Dougherty-Early-Grady-Irwin-Lanier-Lee-Lowndes-Miller-
Mitchell-Quitman-Randolph-Seminole-Terrell-Thomas-Tift-
Turner-Worth.
Fire Weather Watch Saturday afternoon for Baker-Ben
Hill-Berrien-Brooks-Calhoun-Clay-Colquitt-Cook-Decatur-
Dougherty-Early-Grady-Irwin-Lanier-Lee-Lowndes-Miller-
Mitchell-Quitman-Randolph-Seminole-Terrell-Thomas-Tift-
Turner-Worth.
FL...None.
GM...Small Craft Advisory until Noon EST today for Apalachee Bay-
Coastal waters From Ochlockonee River to Apalachicola FL
out to 20 NM-Coastal waters from Suwannee River to Keaton
Beach FL out 20 NM-Coastal waters from Apalachicola to
Destin FL out 20 NM-Waters from Suwannee River to
Apalachicola FL from 20 to 60 NM-Waters from Apalachicola
to Destin FL from 20 to 60 NM.
&&
$$
SYNOPSIS/SHORT TERM/MARINE...MROCZKA
LONG TERM/AVIATION/FIRE WX...BLOCK
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
255 AM EST FRI Jan 13 2012
.SYNOPSIS...
08Z water vapor and H4 RUC analysis shows an amplified upper level
pattern across the CONUS this morning. Main feature is longwave
troughing covering much of the county to the east of the continental
divide. Within this larger trough we find a closed upper low
spinning over the Ohio Valley and responsible for plenty of ongoing
winter precipitation from the Great Lakes to the NE states. The base
of this trough extends down to the northern Gulf coast and will
pivot across our region this morning. Early morning satellite
imagery shows areas of high level cirrus streaming across our skies
ahead of the trough axis and associated with upper level jet energy
aligned along the northern Gulf Coast.
At the surface,
Cold front which crossed the forecast area on Thursday continues to
move south and east over the FL peninsula. In the wake of this
front, a ridge of high pressure is building eastward along the Gulf
coast delivering a cooler and drier airmass. Temperatures will
continue a slow slide downward through the pre-dawn hours reaching
the lower/middle 30s by sunrise to the NW of a PC to Tallahassee to
Valdosta line, and upper 30s to low 40s further south and east.
&&
.SHORT TERM (TODAY THROUGH SUNDAY)...
Today,
High pressure centered over Texas will continue to ridge eastward to
our region through the day. The ridge will supply us with a fair,
dry, and cool forecast to end the work week. Will call it mostly
sunny, however there will be some passing cirrus this morning across
the Big Bend zones, and then additional cirrus arriving from the
west late in the day ahead of yet another mid-level shortwave. With
CAA ongoing this morning, temperatures will be slow to respond.
850mb temps will be lowering through the day, with the 0C line
dipping down close to KDHN and KABY. With this cooler low level
airmass in place, expecting high temperatures by mid afternoon to
generally reach the lower 50s (middle 50s down toward KCTY).
Tonight,
Gradient will weaken as the ridge axis continue to build closer to
the region. In terms of a radiational cooling setup, the high
position is certainly not ideal, however it isn`t terrible either.
It is likely that de-coupling of the boundary layer will eventually
take place, although it may take much of the night to occur. With
this in mind, do not anticipate much in the way of hard freeze
conditions, however much of the forecast area will experience
sub-freezing temperatures during the late night hours. Normally
colder locations under radiational cooling will briefly drop down
into the middle 20s around sunrise, with most other spots bottoming
out in the upper 20s to lower 30s.
Saturday/Sunday,
After the cold start Saturday morning, high pressure building
overhead will provide the region with a dry and seasonable weekend.
Airmass will begin to recover during Saturday as the longwave
mid-level trough begins to pull away to the NE. High temperatures
will respond, reaching the upper 50s for afternoon highs. The
overall airmass will not be as cool Saturday night, however the
surface high will be almost directly over the forecast area. This
more favorable high position combined with plenty of residual dry
air will allow for a good radiational cooling setup. Expecting
widespread low temperatures by sunrise to reside between 30-35
degrees. Normally colder spots...especially along the I-10 corridor
and Suwannee River Valley will have the potential to briefly reach
the upper 20s. Temperatures rebound further on Sunday after the cold
start, with 850mb temps climbing to 6-8C by the end of the day. With
the high position in close proximity, overall diurnal mixing will be
held in check, but should still be able to mix out our afternoon
temps into the lower/mid 60s.
&&
.LONG TERM (MONDAY THROUGH NEXT FRIDAY)...
The large scale longwave pattern commences fairly amplified. This is
highlighted in the Nrn stream by weak troughing across Wrn states
and extreme Wrn Atlc and ridging in between. Srn stream with weak
troughing Pac Coast to TX and ridging Ewd into extreme Wrn Atlc. At
surface, high along NC/VA coast with ridge axis swwd into
Apalachee Bay. Low in Canada N of MN with cold front Swwd into
Colorado. This place local area in very dry pattern.
During the rest of the period, Wrn upper trough digs Ewd while Srn
stream upper ridge moves offshore with Srn flow becoming nearly
zonal and stays so before weak troughing approaches shifting flow to
SWLY on Fri. At surface, Ewd moving UPR Nrn trough pushes surface
low moves to Srn Great Lakes kicking high into Atlc. Assocd cold
front dragged rapidly Sewd with deep sly flow setup from Gulf. Front
pushed thru CWA Tues night exiting Wed morn Ern zones bringing sct
shwrs and isold tstms Tues into Wed. In its wake strong high builds
SEWD from Srn Plains Ewd spreading a reinforcing shot of cold and
very dry air across local region Wed into Fri. By end of period high
pushed offshore with next low moving newd into TN valley dragging
trailing cold front to Wrn Gulf. In response, onshore flow with
increasing chances of rain commences again across local area by end
of Fri.
Forecast will show Sct pops Tues aftn into Wed. Otherwise nil pops
thru period. Ahead of the front min temps will be around 10 degrees
above climo Mon and Tues nights dropping to at or below climo Wed
and Thurs nights and may reach freezing in coldest locales. Max
temps commence at least 10 degrees above climo on Tues dropping to
at or below climo on Wed then inching up to a few degrees above
climo by Fri. Average inland min/max temps are 39/62.
&&
.MARINE
A ridge of high pressure will begin to build over the forecast
waters today in the wake of a cold front. Advisory level northwest
winds will diminish through the day, and expect the current advisory
to be dropped later this morning or early this afternoon. After a
round of cautionary level winds tonight, high pressure will build
overhead for much of the weekend keeping winds and seas below
headline criteria. Winds will begin to pick up once again out of the
east and southeast early next week as the ridge of high pressure
exits the region.
&&
.AVIATION (THROUGH 06Z SATURDAY)...
Wind speeds will continue to be in the 10 kt range and locally gusty
until 09z before diminishing to around or under 10kts until it
becomes near calm after sunset. Aside from a scattering of low level
clouds, expect only cirrus to stream over the region thru 06z Sat.
&&
.FIRE WEATHER...
A very dry airmass will settle in across the region through
Saturday, with RH values dropping into the lower 20s each afternoon.
Durations of critical RH will be right around 4 hours across SE
AL/SW GA for both days with driest values across SE ALA and SW GA. A
Red Flag warning has been issued for the SE ALA/GA counties for this
afternoon. Altho critical RH values will be realized over N FL,
neither ERC, winds or dispersion red flag values will be realized so
no warning was issued. Similar conditions are expected on Saturday
and a fire weather watch remains in effect for the GA/AL counties.
The airmass will slowly moisten Sun thru Tues then dry out again on
Wed into Thurs in the wake of a cold front.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 52 27 58 29 65 / 0 0 0 0 0
Panama City 53 34 59 38 63 / 0 0 0 0 0
Dothan 51 29 59 33 62 / 0 0 0 0 0
Albany 51 27 58 31 61 / 0 0 0 0 0
Valdosta 52 27 57 31 61 / 0 0 0 0 0
Cross City 56 27 59 30 65 / 0 0 0 0 0
Apalachicola 52 35 57 34 63 / 0 0 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...Red Flag Warning from Noon today to 4 PM CST this afternoon for
Coffee-Dale-Geneva-Henry-Houston.
Fire Weather Watch Saturday afternoon for Coffee-Dale-Geneva-
Henry-Houston.
GA...Red Flag Warning from 1 PM to 5 PM EST this afternoon for Baker-
Ben Hill-Berrien-Brooks-Calhoun-Clay-Colquitt-Cook-Decatur-
Dougherty-Early-Grady-Irwin-Lanier-Lee-Lowndes-Miller-
Mitchell-Quitman-Randolph-Seminole-Terrell-Thomas-Tift-
Turner-Worth.
Fire Weather Watch Saturday afternoon for Baker-Ben
Hill-Berrien-Brooks-Calhoun-Clay-Colquitt-Cook-Decatur-
Dougherty-Early-Grady-Irwin-Lanier-Lee-Lowndes-Miller-
Mitchell-Quitman-Randolph-Seminole-Terrell-Thomas-Tift-
Turner-Worth.
FL...None.
GM...Small Craft Advisory until Noon EST today for Apalachee Bay-
Coastal waters From Ochlockonee River to Apalachicola FL
out to 20 NM-Coastal waters from Suwannee River to Keaton
Beach FL out 20 NM-Coastal waters from Apalachicola to
Destin FL out 20 NM-Waters from Suwannee River to
Apalachicola FL from 20 to 60 NM-Waters from Apalachicola
to Destin FL from 20 to 60 NM.
&&
$$
SYNOPSIS/SHORT TERM/MARINE...MROCZKA
LONG TERM/AVIATION/FIRE WX...BLOCK
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1219 PM EST FRI JAN 13 2012
.AVIATION... / 18Z TAFS /
TRANSITION TO PURE LAKE EFFECT SNOW SHOWERS TAKING PLACE WITH
PRIMARY IMPACT ANTICIPATED THIS AFTERNOON AND EVENING AT SBN. AS
IS THE NATURE WITH LAKE EFFECT VISIBILITIES OFTEN BOUNCE BACK AND
FORTH BETWEEN LIFR/IFR/MVFR AND EXPECT THIS AT SBN THIS AFTN/EVE.
MAINLY MVFR CIGS THROUGH THE PERIOD AT FWA WITH SCT SNOW SHOWERS
POSSIBLY REDUCING VISBY`S AT TIMES THIS AFTN. A GRADUAL
IMPROVEMENT TO HIGHER END MVFR CIGS CAN BE EXPECTED LATE TONIGHT
INTO TOMORROW MORNING AS THE FLOW BACKS AND LE SHSN`S SHIFT NORTH
OF THE TERMINALS. OTHERWISE...GUSTY WESTERLY WINDS WILL FINALLY
BEGIN TO RELAX BY EARLY THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 414 AM EST FRI JAN 13 2012/
SHORT TERM...
MID LVL DEFORMATION ZONE CONTS TO PIVOT EWD ACRS CWA THIS MORNING IN
RESPONSE TO UPR LOW LIFTING OUT OF ERN OH. BROAD/DEEP MSTR PLUME
REMAINS ENTRENCHED UPSTREAM WITHIN DEEP CYCLONIC FLW OVR THE WRN
LAKES AND WHICH PRESENTS SOMEWHAT OF A PROBLEM GOING FORWARD THROUGH
THIS MORNING. SNOWFALL ACCUMS SO FAR RANGE FM 3-4 INCHES NORTHWEST
TO LESS THAN 1 INCH ERN HALF THANKS SOLELY TO MID LVL DRY SLOT THAT
WRAPPED IN ALG ERN SIDE OF CLOSING MID LVL CIRC YDA. HWVR SFC TROUGH
HAS PIVOTED INLAND ACRS BERRIEN/LAPORTE COUNTIES AS OF 09Z AND
RESULTED IN A SEQUENTIAL BLOSSOMING IN HIGHER RADAR RTNS OF
25-30 DBZ INDICATING WIDESPREAD MOD-HVY SNOW ONGOING NOW GENERALLY
ALG A LINE FM KIRS...KASW...KRCR. XPC FURTHER CONSOLIDATION
/DEFINITION TO LK BANDS BTWN NOW AND 15Z AS LL WIND FIELD BECOMES
BTR DEFINED AND OBSVD IN RECENT RADAR TRENDS. IN ADDN...INLAND THERMAL
MODIFICATION HAS BEEN QUITE ROBUST W/5-10 DEGREES WARMING NOTED
OVERNIGHT AND SHLD CONT TO PROMOTE INTENSE LL FRONTOGENESIS ESP INLAND
THROUGH THIS AFTN AND THEREIN LIES THE BIGGEST PROBLEM. MIX OF
00Z-06Z HIGHRES GUIDANCE WAVERS CONSIDERABLY ON PLACEMENT OF SRN
EDGE OF LK ENHANCEMENT THIS MORNING BFR GIVING AWAY TO PURE LK
EFFECT BY THIS AFTN W/AN IMPLIED ADDNL 3-4 INCHES OF SNOW FM
12-00Z. PRIOR 00-03Z RUC FCST TREND LOOKED CLOSE UPSTREAM YET WAS
TOO FAR EAST W/ALIGNMENT AT 06Z AND TOO PROGRESSIVE. HWVR 06Z FCST
OFF EVEN FURTHER. NAM12 LIES MIDWAY BTWN NMM/ARW SOLUTIONS SO A
COMBO OF THOSE THREE SHLD SUFFICE THROUGH AFTN BFR SWITCHING TO
BLENDED HIGHRES PLACEMENT. THUS NRN 2 TIERS OF WARNING WILL CONT
THROUGH 00Z W/LIKELY EXTENSION NEEDED THIS EVENING PENDING PRIMARY
LK BAND EVOLUTION THROUGH THIS MORNING. THIS REMAINS QUITE
UNCERTAIN...AND TIED TO WHETHER ERN BAND THROUGH CASS/ST
JOE/LAGRANGE OR WRN BAND THROUGH LAPORTE/ST JOE/ELKHART DOMINATES
AND LTL DEFINITIVE SIGNAL SEEN YET IN OBSVNL TRENDS THIS MORNING
TO GIVE A NOD ONE WAY OR THE OTHER.
AS FOR HIGHLIGHTS...SRN WARNING SEGMENT CONSISTING OF
STARKE/MARSHALL/KOSCIUSKO WILL BE DOWNGRADED. WILL HOLD
W/ADVISORY AREA AS LARGER AREA OF SYNOPTICALLY ENHANCED SHSN
WORKS THROUGH THE AREA THIS MORNING W/GENERAL 1-2 INCHES ADDNL
XPCD THROUGH 18Z. HWVR SW ZONES WILL LIKELY BE DROPPED AT SOME
POINT PRIOR TO EXPIRATION.
PRIMARY LK BAND THROUGH SW MI INTO NRN IN PROGGED TO REMAIN QUITE
INTENSE INTO THIS EVENING AND WILL LIKELY ADD ANOTHER 1-3 INCHES
HWVR ERODING INVERSION HGTS AND GENERAL DRYING ALOFT SUGGEST
INTENSITY WILL BE LIMITED W/GREATER ACCUMS CONFINED TO
LAPORTE/BERRIEN AND CASS. OTHERWISE SFC GRADIENT WKNS RAPIDLY LT
THIS AFTN W/BLSN ENDING.
UPSTREAM CLIPPER PUSHING THROUGH WRN ALBERTA THIS MORNING WILL DIVE
QUICKLY SEWD TONIGHT AND INTO THE OH VALLEY SAT AFTN. CERTAINLY A
LACK OF MSTR OVERTOP RETREATING ARCTIC WEDGE HWVR GOING GRIDDED POPS
LOOK REASONABLE AND MAINTAINED. PRIMARY CHG WAS TO BLEND TWD COLDER
MOS SPLIT ON MAX TEMPS.
LONG TERM.../SUNDAY THROUGH THURSDAY/
UPPER LEVEL FLOW WILL AMPLIFY SOMEWHAT FOR THE START OF THE NEW
WEEK. THIS WILL ALLOW FOR MODERATING TEMPERATURES BACK TO NEAR OR
ABOVE NORMAL LEVELS BEFORE THE NEXT TROUGH BRINGS PRECIP AND COLDER
WEATHER BACK TO THE AREA.
RAPID WAA WILL BE UNDERWAY DURING THE DAY SUNDAY AS 850 MB TEMPS
CLIMB A GOOD 5 TO 10 DEGREES C REACHING TO +2 TO -3 C BY SUNDAY
EVENING. EVEN WARMER TEMPS WILL BE ADVECTED IN SUNDAY NIGHT INTO
MONDAY AS LL FLOW RAMPS UP ALLOWING FOR MOST AREAS TO +3 TO +6 C IN
THE LOW LEVELS BY MONDAY EVENING. CONCERNS FOR SEEING THESE WARMER
TEMPS AT THE SURFACE REMAIN AS A RESULT OF COMBINATION OF AT LEAST
SOME SNOWPACK /ALTHOUGH MAYBE NOT AS MUCH AS ORIGINALLY THOUGHT/ AND
INCREASING CLOUD COVER ASSOCIATED WITH THE APPROACHING SYSTEM. HAVE
OPTED TO HAVE FEW CHANGES TO TEMPS SUNDAY AND MONDAY FOR THE TIME
BEING. LIGHT PRECIP IS STILL POSSIBLE AS LL MSTR WILL INCREASE AND
AT LEAST SOME LOW LEVEL LIFT WILL TAKE PLACE. IF PRECIP WAS TO
ARRIVE FAST ENOUGH MONDAY MORNING...THERE COULD BE A PERIOD OF
FREEZING PRECIP...BUT TEMPS SHOULD CLIMB FAIRLY QUICK ABOVE FREEZING
AND KEEP THIS THREAT TO A MINIMUM.
BEST CHANCE FOR RAINFALL WILL BE MONDAY NIGHT AS COLD FRONT
APPROACHES THE AREA WITH LOW PRESSURE TRACKING ALONG IT. CONFIDENCE
IN ANY ONE MODEL SOLUTION NOT VERY HIGH WITH NORMALLY FAVORED ECMWF
FLIP FLOPPING BETWEEN NORTHERN ENERGY REMAINING STRONGER WITH SFC
LOW ACROSS NORTHERN GREAT LAKES...AND SOUTHERN ENERGY STRENGTHENING
ALLOWING FOR DEEPENING LOW PRESSURE OVER THE FORECAST AREA ON
TUESDAY. WILL MAINTAIN LIKELY POPS MONDAY NIGHT AND HIGHER END POPS
CHC TO LOW END LIKELY TUESDAY FOR CONSISTENCY SAKE. PTYPE SHOULD BE
ALL RAIN MONDAY NIGHT BUT COULD BE RAIN OR MIX OF RAIN/SNOW ON
TUESDAY DEPENDING ON TRACK OF SFC LOW. RUSH OF COLD AIR WILL ARRIVE
ONCE AGAIN WITH TEMPS FALLING BACK BELOW NORMAL INTO THE 20S AND
REMAINING THAT WAY THROUGH THE REMAINDER OF THE PERIOD. YET ANOTHER
DISTURBANCE WILL ARRIVE FOR WEDS NGT INTO THURS BRINGING ANOTHER
CHANCE FOR SNOW.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER STORM WARNING UNTIL 7 AM EST /6 AM CST/ SATURDAY FOR
INZ003>006-008.
WINTER WEATHER ADVISORY UNTIL 1 AM EST SATURDAY FOR INZ007-009.
MI...WINTER STORM WARNING UNTIL 7 AM EST SATURDAY FOR MIZ077>080.
WINTER WEATHER ADVISORY UNTIL 1 AM EST SATURDAY FOR MIZ081.
OH...NONE.
LM...GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
SHORT TERM...T
LONG TERM...FISHER
AVIATION...STEINWEDEL
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
414 AM EST FRI JAN 13 2012
.SHORT TERM...
MID LVL DEFORMATION ZONE CONTS TO PIVOT EWD ACRS CWA THIS MORNING IN
RESPONSE TO UPR LOW LIFTING OUT OF ERN OH. BROAD/DEEP MSTR PLUME
REMAINS ENTRENCHED UPSTREAM WITHIN DEEP CYCLONIC FLW OVR THE WRN
LAKES AND WHICH PRESENTS SOMEWHAT OF A PROBLEM GOING FORWARD THROUGH
THIS MORNING. SNOWFALL ACCUMS SO FAR RANGE FM 3-4 INCHES NORTHWEST
TO LESS THAN 1 INCH ERN HALF THANKS SOLELY TO MID LVL DRY SLOT THAT
WRAPPED IN ALG ERN SIDE OF CLOSING MID LVL CIRC YDA. HWVR SFC TROUGH
HAS PIVOTED INLAND ACRS BERRIEN/LAPORTE COUNTIES AS OF 09Z AND
RESULTED IN A SEQUENTIAL BLOSSOMING IN HIGHER RADAR RTNS OF
25-30 DBZ INDICATING WIDESPREAD MOD-HVY SNOW ONGOING NOW GENERALLY
ALG A LINE FM KIRS...KASW...KRCR. XPC FURTHER CONSOLIDATION
/DEFINITION TO LK BANDS BTWN NOW AND 15Z AS LL WIND FIELD BECOMES
BTR DEFINED AND OBSVD IN RECENT RADAR TRENDS. IN ADDN...INLAND THERMAL
MODIFICATION HAS BEEN QUITE ROBUST W/5-10 DEGREES WARMING NOTED
OVERNIGHT AND SHLD CONT TO PROMOTE INTENSE LL FRONTOGENESIS ESP INLAND
THROUGH THIS AFTN AND THEREIN LIES THE BIGGEST PROBLEM. MIX OF
00Z-06Z HIGHRES GUIDANCE WAVERS CONSIDERABLY ON PLACEMENT OF SRN
EDGE OF LK ENHANCEMENT THIS MORNING BFR GIVING AWAY TO PURE LK
EFFECT BY THIS AFTN W/AN IMPLIED ADDNL 3-4 INCHES OF SNOW FM
12-00Z. PRIOR 00-03Z RUC FCST TREND LOOKED CLOSE UPSTREAM YET WAS
TOO FAR EAST W/ALIGNMENT AT 06Z AND TOO PROGRESSIVE. HWVR 06Z FCST
OFF EVEN FURTHER. NAM12 LIES MIDWAY BTWN NMM/ARW SOLUTIONS SO A
COMBO OF THOSE THREE SHLD SUFFICE THROUGH AFTN BFR SWITCHING TO
BLENDED HIGHRES PLACEMENT. THUS NRN 2 TIERS OF WARNING WILL CONT
THROUGH 00Z W/LIKELY EXTENSION NEEDED THIS EVENING PENDING PRIMARY
LK BAND EVOLUTION THROUGH THIS MORNING. THIS REMAINS QUITE
UNCERTAIN...AND TIED TO WHETHER ERN BAND THROUGH CASS/ST
JOE/LAGRANGE OR WRN BAND THROUGH LAPORTE/ST JOE/ELKHART DOMINATES
AND LTL DEFINITIVE SIGNAL SEEN YET IN OBSVNL TRENDS THIS MORNING
TO GIVE A NOD ONE WAY OR THE OTHER.
AS FOR HIGHLIGHTS...SRN WARNING SEGMENT CONSISTING OF
STARKE/MARSHALL/KOSCIUSKO WILL BE DOWNGRADED. WILL HOLD
W/ADVISORY AREA AS LARGER AREA OF SYNOPTICALLY ENHANCED SHSN
WORKS THROUGH THE AREA THIS MORNING W/GENERAL 1-2 INCHES ADDNL
XPCD THROUGH 18Z. HWVR SW ZONES WILL LIKELY BE DROPPED AT SOME
POINT PRIOR TO EXPIRATION.
PRIMARY LK BAND THROUGH SW MI INTO NRN IN PROGGED TO REMAIN QUITE
INTENSE INTO THIS EVENING AND WILL LIKELY ADD ANOTHER 1-3 INCHES
HWVR ERODING INVERSION HGTS AND GENERAL DRYING ALOFT SUGGEST
INTENSITY WILL BE LIMITED W/GREATER ACCUMS CONFINED TO
LAPORTE/BERRIEN AND CASS. OTHERWISE SFC GRADIENT WKNS RAPIDLY LT
THIS AFTN W/BLSN ENDING.
UPSTREAM CLIPPER PUSHING THROUGH WRN ALBERTA THIS MORNING WILL DIVE
QUICKLY SEWD TONIGHT AND INTO THE OH VALLEY SAT AFTN. CERTAINLY A
LACK OF MSTR OVERTOP RETREATING ARCTIC WEDGE HWVR GOING GRIDDED POPS
LOOK REASONABLE AND MAINTAINED. PRIMARY CHG WAS TO BLEND TWD COLDER
MOS SPLIT ON MAX TEMPS.
&&
.LONG TERM.../SUNDAY THROUGH THURSDAY/
UPPER LEVEL FLOW WILL AMPLIFY SOMEWHAT FOR THE START OF THE NEW
WEEK. THIS WILL ALLOW FOR MODERATING TEMPERATURES BACK TO NEAR OR
ABOVE NORMAL LEVELS BEFORE THE NEXT TROUGH BRINGS PRECIP AND COLDER
WEATHER BACK TO THE AREA.
RAPID WAA WILL BE UNDERWAY DURING THE DAY SUNDAY AS 850 MB TEMPS
CLIMB A GOOD 5 TO 10 DEGREES C REACHING TO +2 TO -3 C BY SUNDAY
EVENING. EVEN WARMER TEMPS WILL BE ADVECTED IN SUNDAY NIGHT INTO
MONDAY AS LL FLOW RAMPS UP ALLOWING FOR MOST AREAS TO +3 TO +6 C IN
THE LOW LEVELS BY MONDAY EVENING. CONCERNS FOR SEEING THESE WARMER
TEMPS AT THE SURFACE REMAIN AS A RESULT OF COMBINATION OF AT LEAST
SOME SNOWPACK /ALTHOUGH MAYBE NOT AS MUCH AS ORIGINALLY THOUGHT/ AND
INCREASING CLOUD COVER ASSOCIATED WITH THE APPROACHING SYSTEM. HAVE
OPTED TO HAVE FEW CHANGES TO TEMPS SUNDAY AND MONDAY FOR THE TIME
BEING. LIGHT PRECIP IS STILL POSSIBLE AS LL MSTR WILL INCREASE AND
AT LEAST SOME LOW LEVEL LIFT WILL TAKE PLACE. IF PRECIP WAS TO
ARRIVE FAST ENOUGH MONDAY MORNING...THERE COULD BE A PERIOD OF
FREEZING PRECIP...BUT TEMPS SHOULD CLIMB FAIRLY QUICK ABOVE FREEZING
AND KEEP THIS THREAT TO A MINIMUM.
BEST CHANCE FOR RAINFALL WILL BE MONDAY NIGHT AS COLD FRONT
APPROACHES THE AREA WITH LOW PRESSURE TRACKING ALONG IT. CONFIDENCE
IN ANY ONE MODEL SOLUTION NOT VERY HIGH WITH NORMALLY FAVORED ECMWF
FLIP FLOPPING BETWEEN NORTHERN ENERGY REMAINING STRONGER WITH SFC
LOW ACROSS NORTHERN GREAT LAKES...AND SOUTHERN ENERGY STRENGTHENING
ALLOWING FOR DEEPENING LOW PRESSURE OVER THE FORECAST AREA ON
TUESDAY. WILL MAINTAIN LIKELY POPS MONDAY NIGHT AND HIGHER END POPS
CHC TO LOW END LIKELY TUESDAY FOR CONSISTENCY SAKE. PTYPE SHOULD BE
ALL RAIN MONDAY NIGHT BUT COULD BE RAIN OR MIX OF RAIN/SNOW ON
TUESDAY DEPENDING ON TRACK OF SFC LOW. RUSH OF COLD AIR WILL ARRIVE
ONCE AGAIN WITH TEMPS FALLING BACK BELOW NORMAL INTO THE 20S AND
REMAINING THAT WAY THROUGH THE REMAINDER OF THE PERIOD. YET ANOTHER
DISTURBANCE WILL ARRIVE FOR WEDS NGT INTO THURS BRINGING ANOTHER
CHANCE FOR SNOW.
&&
.AVIATION...
DIFFICULT NR TERM AS LK ENHANCEMENT GIVES WAY TO PURE LK EFFECT SHSN.
XPC POOR FLIGHT CONDS TO CONT AT KSBN INTO THIS AFTN ESP IN LIGHT
OF LL WIND FIELD REORGANIZING THIS MORNING AND SIGNS OF RENEWED LK
BAND DVLPMNT. 06Z ISSUANCE LOOKS ON TRACK LIFR CONDS EARLY ON
GIVING WAY TO IFR UNTIL LT THIS AFTN. INTENSE SFC GRADIENT THIS
MORNING WILL CONT THROUGH MID AFTN BFR DIMINISHING. OTHERWISE
IMPROVING CONDS TO MVFR XPCD THIS EVENING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 1 PM EST /NOON CST/ THIS AFTERNOON
FOR INZ012>018-020-022>027-032>034.
WINTER STORM WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
INZ003>006-008.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR INZ007-
009.
MI...WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MIZ077>080.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ081.
OH...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR OHZ001-
002-004-005-015-016-024-025.
LM...GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
SHORT TERM...T
LONG TERM...FISHER
AVIATION...T
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
558 PM CST SAT JAN 14 2012
.AVIATION...
ROUGHLY 20-30 MI BAND OF LIGHT SNOW AND FLURRIES TO SWEEP THROUGH
KDBQ AND KMLI NEXT COUPLE OF HRS. MVFR CONDITIONS WILL BE
ASSOCIATED WITH THIS ACTIVITY. IN THE WAKE... STRATUS WITH
MVFR CIGS OF 1500-2500 FT AGL WILL LINGER AND PERSIST THROUGH THE
REST OF EVE BEFORE GRADUALLY PUSHING EAST OVRNGT... WITH
CONDITIONS RETURNING TO VFR FROM W TO E THROUGH 13Z SUN AND
REMAINING VFR REST OF DAY. SOME LIGHT FOG WILL BE POSSIBLE TOWARD
DAYBREAK WHERE SKIES CLEAR. WINDS GENERALLY LIGHT SOUTHERLY TNGT
WILL INCREASE TO 10-15 KTS BY MID AM SUN THEN BECOME GUSTY BY SUN
AFTN AT 15-25 KTS WITH LOCALLY HIGHER GUSTS AS PRESSURE GRADIENT
STRENGTHENS.
&&
.PREV DISCUSSION... /ISSUED 330 PM CST SAT JAN 14 2012/
SYNOPSIS...
A COUPLE OF CLIPPER TYPE SYSTEMS WERE RESPONSIBLE FOR SOME LIGHT
SNOW OVER THE REGION THIS MORNING AND THIS AFTERNOON. THE SURFACE
LOW ASSOCIATED WITH ONE OF THE SYSTEM PASSED JUST TO OUR SOUTH THIS
MORNING SPREADING SOME LIGHT SNOW OVER THE SOUTHERN COUNTIES.
ANOTHER LOW WAS MOVING THOUGH NORTHERN MN EARLY THIS AFTERNOON WITH
A WARM FRONT EXTENDING SOUTH INTO WESTERN IOWA. SOME LIGHT SNOW AND
FLURRIES WERE OCCURRING JUST AHEAD OF THE FRONT. THE CLIPPER TYPE
SYSTEMS WERE EMBEDDED IN NORTHWEST FLOW BOUNDED BY A LARGE TROF OVER
THE GREAT LAKES AND OHIO VALLEY AND RIDGING OVER THE ROCKIES.
ANOTHER VIGOROUS S/W WAS MOVING INTO BRITISH COLUMBIA AND THE
PACIFIC NW WITH 200 METER 12 HOUR HEIGHT FALLS NOTED ON THE MORNING
500MB ANALYSIS.
SHORT TERM...TONIGHT AND SUNDAY...
THE NORTHERN MN LOW AND ITS ASSOCIATED WARM FRONT WEAKEN THIS
EVENING AS LOW LEVEL FLOW OVER THE CENTRAL AND NORTHERN PLAINS
BACKS AHEAD OF THE PACIFIC NW S/W AND ITS STRONGER SURFACE LOW
MOVING INTO SOUTHERN SASKATCHEWAN BY SUNDAY MORNING. THE LIGHT
SNOW AHEAD OF THE WARM FRONT HAS BEEN STEADILY WEAKENING AS IT
MOVED OVER CENTRAL IOWA THIS AFTERNOON. THE CONTINUATION OF THIS
WEAKENING TREND IS SUPPORTED BY LOW/MID LEVEL FGEN DECREASING
OVER IA AND BECOMING MORE FOCUSED TO OUR NORTH THIS EVENING.
RECENT HRRR RUNS ALSO SUPPORT A BETTER THREAT OF MEASURABLE SNOW
NORTH OF THE CWFA. HAVE CUT POPS BACK TO SLIGHT CHANCE AT MOST...AND
LIMITED THOSE TO THE NORTHEAST THIRD OF THE FORECAST AREA FOR THIS
EVENING. AFTER MIDNIGHT EXPECT PARTLY TO MOSTLY CLOUDY SKIES WITH
MID LEVEL WAA ADVECTION CLOUDS MOVING THROUGH THE AREA AS WELL AS
SOME CI SPREADING IN WITH THE FORECAST AREA IN THE VICINITY OF THE
RIGHT ENTRANCE REGION OF AN H3 JET STREAK FROM MN/WI INTO NRN IN
AT 12Z SUNDAY. SOME FLURRIES WERE CONSIDERED IN THE WEST WITH THE
MID LEVEL WAA...BUT PRESSURE CONDENSATION DEFICITS WERE QUITE HIGH
BELOW 400MB...SO OPTED NOT TO MENTION FLURRIES. TEMPERATURES WILL
BE DIFFICULT WITH THE SNOW COVER...LIGHT WINDS AND PATCHY NATURE
OF THE CLOUDS. ANY CLEARING WILL ALLOW TEMPERATURES TO PLUMMET
OVER THE NORTH. LATEST TIMING OF THE CENTRAL IA CLOUDS INTO/THROUGH
THE CWFA SUGGEST THEY WILL NOT REACH THE EASTERN COUNTIES UNTIL A FEW
HOURS AFTER SUNSET SO ALLOWED FOR A SIGNIFICANT DROP EARLY THIS
EVENING IN NW IL WITH MINS IN THE SINGLE DIGITS.
SUNDAY THE REGION WILL BE DOMINATED BY SOUTHERLY FLOW IN THE LOW
LEVELS AS THE NORTHERN PLAINS SURFACE LOW TRACKS ALONG THE CANADIAN
BORDER AND DRY WESTERLY MID LEVEL FLOW. THIS SHOULD GIVE THE REGION
PLENTY OF SUN. KEPT TEMPERATURES IN THIS REGIME JUST ABOVE GUIDANCE
IN THE SOUTH WHERE LITTLE SNOW COVER EXISTS WITH HIGHS IN THE LOW
40S. OVER THE SNOW COVERED NORTH WENT WITH HIGHS IN THE 30S.
.DLF..
LONG TERM...SUNDAY NIGHT THROUGH NEXT SATURDAY...
SUNDAY NIGHT AND MONDAY...LATEST SUITE OF 12Z RUN MODELS IN
GENERALLY GOOD AGREEMENT THIS PERIOD OF SUGGESTING LEAD IMPULSE OF
PACIFIC NW WAVE ENERGY/SEEN CURRENTLY ON WATER VAPOR IMAGERY
ROTATING DOWN ALONG THE B.C. COAST/ TO RIDGE-RIDE NORTH OF THE U.S.
BORDER ACRS SOUTHERN CANADA AND ACRS JAMES BAY INTO MON. ASSOCIATED
SFC FRONT OFF THIS PASSING WAVE PROBABLY TO JUST MAKE IT ACRS
THE FAR NORTHWESTERN CWA BY 12Z...THUS PRE-FRONTAL WAA AND SOME
BOUNDARY LAYER MOISTURE INCREASE LATE AT NIGHT TO PRODUCE A STEADY
TO SLOW TEMP RISE TOWARD DAWN AND LOWS WILL BE FROM MID EVENING
THROUGH 3 AM CST. 50+ KT SOUTHWESTERLY LLJ TO REALLY WAA AND
PRODUCE A WARM WEDGE/INVERSION ALOFT IN THE H85-H7 MB LAYER BY
MONDAY. LIKE PREVIOUS SHIFT STATED...HIGHER DPTS ADVECTED IN AS
WELL AS SOME SNOW MELT JUICED BL TRAPPED UNDER BUILDING INVERSION TO
INDUCE LLVL STRATUS AND FOG LATE SUNDAY NIGHT INTO MON. STILL SOME
QUESTION ON SPEED OF THIS DEVELOPING/MOISTURE INCREASE AND SOME
RECENT SIGNALS OF THE LOW CLOUDS AND FOG REALLY DEVELOPING MORE
CLOSER TO MONDAY MORNING AS OPPOSED TO SUNDAY NIGHT. BUT WILL KEEP
FOG MENTION SUN NIGHT AND MONDAY. INCREASING LIFT AND MID LEVELS
REMAINING DRY ALOFT SUGGEST DRIZZLE GETTING WRUNG OUT OF THIS LLVL
CLOUD DECK...AND IF SFC TEMPS CAN/T CLIMB ABOVE FREEZING TIL DAWN
MONDAY...MAY BE SOME TROUBLE WITH FREEZING DRIZZLE ALONG AND
NORTH OF I-80 FRO AWHILE AND WILL MENTION IN THE ZONES. LOW CLOUDS
AND LLVL SATURATION MAY LIMIT SFC HEATING ENOUGH TO KEEP TEMPS AT
OR BELOW FREEZING UNTIL MID MON MORNING NORTH OF THE HWY 30 AREAS
AND WILL EXTEND FREEZING DRIZZLE MENTION IN THESE AREAS FOR MON
MORNING. FOG TO CONTINUE WELL INTO MON AS WELL. AS SFC BOUNDARY
SAGS AND STALLS OUT ACRS THE CWA PARALLEL TO MEAN SOUTHWESTERLY
STEERING FLOW ON MON...CONTINUED LLVL MOISTURE TRANSPORT AND
CONVERGENCE INTO THIS FEATURE MAY INCREASE/SATURATE MOISTURE
PROFILES DEEP ENOUGH FOR MORE OF A LIGHT RAIN FORMING ACRS MUCH OF
THE SOUTHEAST TWO THIRDS OF THE DVN CWA BY LATE MORNING AND INTO THE
AFTERNOON. THICK LLVL CLOUDS...FOG...SNOW MELT PROCESS...AND
SATURATION MAY LIMIT SFC HEATING WITH HIGHS MORE IN THE MID TO UPPER
30S IN THE SOUTH HALF AS OPPOSED TO MODEL GUIDANCE UPPER 30S TO LOWER
40S. TEMPS MAY ACTUALLY HAVE TROUBLE WARMING ABOVE 32 IN THE FAR
NORTHERN CWA/NORTH OF CID IA TO FREEPORT IL/ WHICH COULD EXTEND A
FREEZING DRIZZLE OR VERY LIGHT FREEZING RAIN SCENARIO WELL INTO THE
AFTERNOON IN THOSE AREAS. APPROACH OF MAIN UPPER TROF FROM THE
PACIFIC NW AND ACRS THE PLAINS COULD INDUCE SOME LLVL WAVE
DEVELOPMENT ALONG ON THE FRONT WHICH COULD EXTEND SOME PRECIP ALMOST
DEF ZONE STYLE IN THE EASTERN CWA MONDAY EVENING. WITH TOP-DOWN
COOLING AND SATURATION TAKING PLACE...THE RAIN COULD SWITCH OVER TO A
MIX OR ALL SNOW WITHIN A FEW HOURS AFTER SUNSET WITH SOME LIGHT
SLUSHY ACCUMULATION ALONG THE EASTERN I-80 CORRIDOR. TEMPS TO CRASH
LATE MON NIGHT INTO TUE MORNING IN LLVL COLD CONVEYOR WITH VALUES
RANGING FROM THE MID TEENS IN THE NORTHWEST...TO THE MID 20S IN THE
FAR EAST AND SOUTHEAST.
TUESDAY AND WEDNESDAY...THE LLVL CYCLONE REALLY TAKES OFF/DEEPENS
ACRS THE CENTRAL GRT LKS ON TUE...BUT THE BRUNT OF THE PASSING UPPER
TROF ACRS THE LOCAL AREA STILL TO PROBABLY TO MAKE FOR WIDESPREAD
LIGHT SNOWS ACRS MOST OF THE DVN CWA THROUGH LATE TUE AFTERNOON
BEFORE THE UPPER TROF AXIS PASSES ACRS LK MI BY TUE EVENING AND
SUBSIDENCE TAKES OVER IN ITS WAKE. POTENTIAL FOR SOME 1-2 INCH
AMOUNTS BY TUE EVENING MAINLY ALONG AND NORTH OF THE HWY 30
CORRIDOR...BUT MORE OF A STORY WILL BE THE COLD AND NORTHWESTERLY
SFC WINDS GUSTING UP OVER 30 MPH AT TIMES WITH WIND CHILLS NEAR
ZERO IN THE AFTERNOON. CLEARING AND COLD CONDITIONS TUE NIGHT WITH
PASSING LLVL RIDGE LOBE...SOME LOWS BELOW ZERO POSSIBLE IN AREAS
NORTH OF I80. PASSING CLIPPER ACRS MN/WI IN FRESHLY ESTABLISHED BROAD
NORTH-WESTERLIES...MAY USHER YET ANOTHER FRONT INTO THE CWA BY LATE
WED NIGHT WITH POSSIBLE FLURRIES.
THURSDAY THROUGH SATURDAY...LLVL BAROCLINICITY TO GET ALIGNED
PARALLEL UNDER THESE MEAN FLOW NORTH-WESTERLIES ACRS THE CWA ON
THU...AND ANY PASSING WAVE ALOFT IN THE PROGRESSIVE FLOW COULD WRING
OUT SOME LIGHT SNOW OR FLURRIES ALONG THE LLVL THERMAL RIBBON ON THU
AND WILL CARRY LOW CHC POPS FOR THIS POTENTIAL. BOTH THE 12Z RUN
GFS AND ECMWF NOW PICK UP ON A MORE SUBSTANTIAL TYPE CLIPPER-LIKE
WAVE PROPAGATING DOWN IN THIS FLOW ALONG THE BAROCLINICITY WHICH
UTILIZES SOME GULF MOISTURE FEED FROM THE SOUTH TO PRODUCE 1-3 OR
EVEN 2-4 INCHES OF SNOW ACRS THE NORTH HALF OF THE DVN CWA FROM LATE
THU NIGHT INTO FRI MORNING. WILL KEEP CHC POPS GOING FOR SNOW ON FRI
FOR NOW...AND MAYBE A MIX OF RAIN AND SNOW IN THE SOUTH WITH PRE-
SYSTEM WARM DRAW ALOFT POSSIBLE. FLATTENING FLOW AND POST-SYSTEM
RIDGING MAY BRING A LULL IN THE ACTION FOR LATER FRI NIGHT AND SAT.
SOME SIGNS OF ENOUGH WAA ON SAT AHEAD OF TE NEXT DEVELOPING LARGE
SYSTEM TO DRIVE TEMPS INTO THE MID TO UPPER 30S DEPENDING ON SNOW
COVER BY THAT TIME. ..12..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
327 PM CST FRI JAN 13 2012
.SYNOPSIS...
12Z UA ANALYSIS HAS AN EXTRATROPICAL CYCLONE IN SOUTHEAST CANADA
WITH NUMEROUS TROFS FROM THE TENNESSEE VALLEY BACK INTO THE UPPER
MIDWEST. RADAR TRENDS THROUGH MID AFTERNOON CONTINUE TO SHOW PLENTY
OF FLURRIES AND LIGHT SNOW OVER THE MID MISSISSIPPI VALLEY. CLEARING
UNDER THE CYCLONIC FLOW WAS MAKING SLOW BUT STEADY PROGRESS EASTWARD.
18Z SFC ANALYSIS HAS A COLD FRONT FROM THE EASTERN GREAT LAKES BACK
INTO NORTHEAST ILLINOIS WITH A HIGH PRESSURE RIDGE FROM MINNESOTA
INTO EASTERN TEXAS. A CHINOOK WARM FRONT WAS OVER THE EASTERN PARTS
OF THE DAKOTAS AND NEBRASKA. A WARM FRONT ASSOCIATED WITH THE NEXT
CLIPPER SYSTEM WAS MOVING OUT OF THE NORTHERN ROCKIES. DEW POINTS
UNDER THE HIGH PRESSURE RIDGE WERE IN THE SINGLE DIGITS ABOVE AND
BELOW ZERO. OTHERWISE DEW POINTS WERE IN THE TEENS AND 20S ACROSS
THE MIDWEST AND PLAINS.
&&
.SHORT TERM...TONIGHT AND SATURDAY...
LIGHT SNOW WILL CONTINUE THROUGH LATE AFTERNOON BUT WILL TAPER TO
FLURRIES ONCE SUNSET OCCURS. RUC TRENDS CONTINUE TO SHOW WEAK F
VECTOR CONVERGENCE AND WEAK FRONTOGENETICAL FORCING WILL REMAIN
ACROSS THE AREA INTO THE EARLY EVENING. THAT COMBINED WITH THE
SHALLOW ARCTIC AIR MASS AND A VORT MAX MOVING THROUGH THE CWFA WILL
ALLOW FLURRIES TO PERSIST THROUGH MID EVENING.
CLEARING WILL OCCUR FROM WEST TO EAST DURING THE EVENING AND
OVERNIGHT HOURS. TEMPERATURES SHOULD DROP QUICKLY ONCE CLEARING
OCCURS DUE TO THE SNOW COVER AND LIGHT WINDS. AFTER MIDNIGHT...WAA
CLOUDS FROM THE APPROACHING CLIPPER SYSTEM WILL MOVE INTO THE AREA
AND LIKELY ALLOW TEMPERATURES TO BOTTOM OUT AND SLOWLY RISE.
AFTER 3 AM...ALL MODELS SHOW F VECTOR CONVERGENCE DEVELOPING AGAIN
WITH COLLAPSING CONDENSATION PRESSURE DEFICITS ALONG WITH AN
INCREASE IN FRONTOGENETICAL FORCING. MOISTURE WITH THIS CLIPPER
SYSTEM IS LIMITED BUT FLURRIES AND LIGHT SNOW SHOULD BREAK OUT PRIOR
TO DAWN GENERALLY WEST OF A KIIB TO KPPQ LINE. SCHC/CHC POPS WERE
DONE DUE TO THE LIMITED MOISTURE BUT MAY NEED TO BE RAISED IN THE
EXTREME WEST AND SOUTHWEST PARTS OF THE CWFA.
THE WAA PRECIPITATION WING OF THE CLIPPER SYSTEM WILL MOVE ACROSS
THE WESTERN HALF OR TWO THIRDS OF THE CWFA SATURDAY MORNING.
CONDENSATION PRESSURE DEFICITS REMAIN LOW AND THERE IS F VECTOR
CONVERGENCE WITH SOME FORCING. DURING THE AFTERNOON THE COLD
CONVEYOR BELT PRECIPITATION FROM THE CLIPPER SYSTEM WILL OVERSPREAD
THE ENTIRE AREA BEFORE ENDING FROM THE WEST LATE IN THE AFTERNOON.
AS FOR AMOUNTS...A DUSTING OF ACCUMULATION IS POSSIBLE PRIOR TO
SUNRISE IN THE FAR WEST/SOUTHWEST PARTS OF THE CWFA. ACCUMULATIONS
DURING THE DAY SATURDAY SHOULD RANGE FROM A DUSTING TO ONE HALF
INCH. IT IS CONCEIVABLE THAT ACCUMULATIONS APPROACHING AN INCH MAY
OCCUR OVER THE SOUTHWEST THIRD TO HALF OF THE CWFA. ..08..
.LONG TERM...SATURDAY NIGHT THROUGH NEXT FRIDAY...
ACTIVE/UNSETTLED PATTERN TO PERSIST THROUGH THE PERIOD WITH MANY FCST
CHALLENGES. MAIN STORM SYSTEM THAT BEARS CONSIDERABLE WATCHING IS IN
MON-TUE TIME-FRAME. THIS STORM LOOKS TO BRING WINTRY MIX OF PCPN WITH
POTENTIAL FOR HEADLINES.
SAT NGT... SOME RESIDUAL WEAK LIFT LINGERS INTO THE EVE ACROSS THE NORTH
AS CLIPPER DEPARTS AND WARM FRONT PUSHES THROUGH. NAM AND GFS
BUFR SOUNDINGS SHOW LOSS OF ICE INTRODUCTION WHICH WOULD SUPPORT DRIZZLE
OR FREEZING DRIZZLE. CONCERNS THOUGH THESE MODELS MAY BE OVERDONE WITH
EXTENT OF LOW LEVEL MOISTURE ... A TYPICAL BIAS ESPECIALLY WITH
NAM... ESPECIALLY GIVEN NO SNOW MELT. GIVEN UNCERTAINTIES AND WITH
ANY PCPN JUST TRACE AMOUNTS HAVE LEFT OUT ANY MENTION ATTIM. MAY SEE
TEMPS STEADY OR RISING OVRNGT ESPECIALLY SOUTH WITH ONSET OF LOW LEVEL
WARM ADVECTION.
SUN-SUN NGT... NEXT ARCTIC FRONT TO EMERGE INTO THE PLAINS AND EXPECTED
TO PUSH THROUGH IA AND POSSIBLY BISECTING 12Z MON PER NAM/GFS. HI-RES
ECMWF SLOWER BUT 12Z RUN IS SLIGHTLY FASTER AND MAY BE TRENDING TOWARD
NAM/GFS. DEEPER MOISTURE RETURNS LATE FOR POSSIBLY SOME VERY LIGHT RAIN
OR DRIZZLE AFTER MIDNIGHT... OR VERY LIGHT FREEZING RAIN/DRIZZLE IN SOME
AREAS DEPENDING ON SFC TEMPS WITH NW CWA MOST SUSCEPTIBLE IT APPEARS
ATTIM BUT THIS DEPENDENT ON FRONTAL TIMING. MOST IF NOT ALL OF
AREA SHOULD GET ABOVE FREEZING WITH 40S WIDESPREAD ACROSS THE SW CWA ON
GUSTY SOUTHERLY WINDS.
MON-TUE... STRONG BAROCLINICITY AND COUPLED JET STRUCTURE SUPPORT
CYCLOGENESIS ALONG ARCTIC FRONT... WITH CONSIDERABLE MODEL SPREAD ON
MAGNITUDE/TRACK/TIMING... AND GIVEN HIGHLY DYNAMICAL ENVIRONMENT EXPECT
CONTINUED CHANGES IN MODELS NEXT DAY OR TWO. GFS AND HI-RES ECMWF HAVE
TRENDED DEEPER AND SLOWER... AND MAY CONTINUE TO SEE THIS TREND. BOTTOM
LINE IS MOISTURE AND FORCING SUPPORTS MODERATE QPF EVENT NOT TOO
DISSIMILAR FROM THIS MOST RECENT EVENT. DEPENDING ON FRONT AND SFC LOW
LOCATIONS PCPN TYPES COULD VARY OR TRANSITION FROM RAIN TO FREEZING
RAIN...SLEET AND SNOW ACROSS CWA. THEREFORE... WITH THE WINTRY MIXTURE
THIS SYSTEM WILL BEAR CONSIDERABLE WATCHING IN THE DAYS AHEAD. POPS ARE
IN MOD/HIGH CHC CATEGORY FOR NOW GIVEN UNCERTAINTY WITH TRACK. IN
ADDITION MAY SEE FOG MON WITH AREAS OF DENSE FOG AHEAD OF SFC LOW WITHIN
LOW LEVEL MOISTURE CONVERGENCE.
WED-FRI... MUCH COLDER WITH ANOTHER ARCTIC FRONT SUGGESTED TO ARRIVE
WED THAT MAY NEED POPS IN LATER FCSTS. FOR NOW THOUGH HAVE CHC POPS
THU-FRI AS ENERGY RIPPLES ALONG LOW-MID LEVEL BAROCLINIC ZONE. WINTER HAS
FINALLY ARRIVED. ..05..
&&
.AVIATION...
MVFR CONDITIONS WILL CONTINUE THROUGH 03Z/14 WITH -SN. THE -SN IS
EXPECTED TO TAPER TO FLURRIES WITH SUNSET. VFR WX WILL THEN BE SEEN
AS HIGH PRESSURE MOVES ACRS EASTERN IOWA AND ILLINOIS. THE NEXT
SYSTEM APPROACHES FROM THE NORTHERN PLAINS AFT 06Z/14 WITH -SN
EXPECTED TO DVLP JUST PRIOR TO SUNRISE AT KCID/KBRL. 12Z-18Z/14 MVFR
CONDITIONS WILL AGAIN DVLP AT ALL TAF SITES AS -SN BECOMES MORE
WIDESPREAD. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1126 AM CST FRI JAN 13 2012
.AVIATION...
MVFR CONDITIONS WILL CONTINUE THROUGH 00Z/14 WITH -SN. AFT 00Z/14
VFR CONDITIONS WILL DVLP AT ALL TAF SITES WITH LIGHT WINDS. NEXT
SYSTEM APPROACHES FROM THE NORTHERN PLAINS WITH -SN DVLPG JUST
PRIOR TO SUNRISE AT KCID/KBRL. AFT 12Z/14 MVFR CONDITIONS WILL
AGAIN DVLP AT ALL TAF SITES WITH -SN BECOMING MORE WIDESPREAD.
..08..
&&
.PREV DISCUSSION... /ISSUED 1000 AM CST FRI JAN 13 2012/
UPDATE...
A SIGNIFICANT REVISION IS COMING TO THE OVERALL FCST. WATER VAPOR
SHOWS A NICE VORT MAX ROTATING SOUTHEAST ACROSS IOWA. RADAR
RETURNS ARE EXPANDING ACROSS THE AREA SHOWING -SN DEVELOPING PER
SFC OBS. A DUSTING HAS ALREADY OCCURRED IN THE CID METRO AREA.
PER THE RUC TRENDS...THERE IS WEAK F VECTOR CONVERGENCE ACROSS THE
AREA THAT MAINTAINS THROUGH THE AFTERNOON. FORCING IS WEAK BUT
THERE AND CONDENSATION PRESSURE DEFICITS ARE MODERATELY LOW IN THE
SHALLOW ARCTIC AIR.
BASED ON THIS THE FCST HAS BEEN REVISED TO GO WITH -SN FOR THE
REMAINDER OF THE DAY. ACCUMULATIONS SHOULD ONLY BE A DUSTING BUT
EMBEDDED SNOW SHOWERS MAY RESULT IN LOCALIZED HALF INCH ACCUMULATIONS.
AN UPDATED FCST WILL BE AVAILABLE SHORTLY.
.08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1000 AM CST FRI JAN 13 2012
.UPDATE...
A SIGNIFICANT REVISION IS COMING TO THE OVERALL FCST. WATER VAPOR
SHOWS A NICE VORT MAX ROTATING SOUTHEAST ACROSS IOWA. RADAR
RETURNS ARE EXPANDING ACROSS THE AREA SHOWING -SN DEVELOPING PER
SFC OBS. A DUSTING HAS ALREADY OCCURRED IN THE CID METRO AREA.
PER THE RUC TRENDS...THERE IS WEAK F VECTOR CONVERGENCE ACROSS THE
AREA THAT MAINTAINS THROUGH THE AFTERNOON. FORCING IS WEAK BUT
THERE AND CONDENSATION PRESSURE DEFICITS ARE MODERATELY LOW IN THE
SHALLOW ARCTIC AIR.
BASED ON THIS THE FCST HAS BEEN REVISED TO GO WITH -SN FOR THE
REMAINDER OF THE DAY. ACCUMULATIONS SHOULD ONLY BE A DUSTING BUT
EMBEDDED SNOW SHOWERS MAY RESULT IN LOCALIZED HALF INCH ACCUMULATIONS.
AN UPDATED FCST WILL BE AVAILABLE SHORTLY.
..08..
&&
.AVIATION...
MVFR CONDITIONS CONTINUE ACROSS THE AREA. LIFT FROM AN UPPER LEVEL
DISTURBANCE IS ALLOWING -SN TO BREAK OUT WEST OF THE MISSISSIPPI
WITH MOVEMENT TO THE EAST. BASED ON TRENDS FROM THE RUC MODEL...
MVFR CIGS/VSBYS ARE LIKELY TO PERSIST UNTIL NEARLY 00Z/14. VFR
CONDITIONS ARE EXPECTED TO DVLP AFT 00Z/14.
..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
208 PM MST FRI JAN 13 2012
.SYNOPSIS...
208 PM MST FRI JAN 13 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE SCALE
PATTERN DOMINATED BY TROUGH ACROSS THE EASTERN CONUS...WITH RIDGE
BUILDING ALONG THE PACIFIC COAST. WEDGED BETWEEN THESE TWO
FEATURES...N/NW FLOW CONTINUES ACROSS THE CWA.
DR
&&
.DISCUSSION...
208 PM MST FRI JAN 13 2012
TONIGHT...SHOULD SEE NORTHWEST WINDS OF 10 TO 20 MPH WINDS WITH
HIGHER GUSTS THROUGH MIDNIGHT BEHIND A DEPARTING UPPER LEVEL
DISTURBANCE. AFTER MIDNIGHT WINDS SUBSIDE A BIT INTO THE 10 MPH
RANGE. OVERNIGHT LOWS WILL BE A BIT WARMER THEN THE PAST FEW NIGHTS
AS WARM AIR ALOFT MOVES IN. WILL AIM FOR LOWS GENERALLY IN THE UPPER
TEENS TO LOW 20S IN FAR EASTERN COLORADO...LOW TO MID 20S EAST OF
THE CO/KS BORDER. THIS IS SEVERAL DEGREES WARMER THAN THE MAV AND
MET MOS GUIDANCE.
007
SATURDAY-SUNDAY...H5 RIDGE CONTINUES TO BUILD EAST TOWARDS CWA...WITH
DRY/STABLE AIR MASS IN PLACE THROUGH SUNDAY NIGHT. TEMPERATURES
WILL CONTINUE TO MODERATE OVER THE NEXT FEW DAYS...WITH HIGH TEMPS
IN THE 50S SATURDAY...AND MID/UPPER 50S ON SUNDAY. CONSIDERING
TEMPS ALOFT SAT/SUN NIGHTS...BUMPED LOWS TO THE UPPER 20S. THIS IS
ABOUT 5-10F ABOVE MOS GUIDANCE...HOWEVER CONSIDERING TEMPS ALOFT
AND POSSIBLE SKY COVER SUN NIGHT...THIS MAY STILL BE TOO COOL.
MONDAY-MONDAY NIGHT...TROUGH DEVELOPING OVER THE PACIFIC NW OVER THE
WEEKEND WILL PROGRESS EAST ACROSS THE GREAT BASIN TOWARDS THE CWA
MONDAY. GUIDANCE STILL DIFFERS BY ABOUT 6HR ON TIMING OF ASSOCIATED
COLD FRONT MONDAY...HOWEVER OVERALL TREND HAS BEEN TO SPEED UP
ARRIVAL...WITH FRONTAL PASSAGE LIKELY BY MIDDAY. PRECIP ASSOCIATED WITH
LARGE SCALE ASCENT ALONG LEADING EDGE OF TROUGH AXIS LOOKS TO ARRIVE
FROM THE NW LATE MONDAY AFTERNOON...QUICKLY MOVING EAST THROUGH THE
EVENING HOURS. GUIDANCE IN GOOD AGREEMENT ON STABLE/DRY AIR QUICKLY
MOVING IN AFTER 06Z...SO I TRENDED FORECAST IN THAT DIRECTION. I
KEPT BEST CHANCES DURING THE EVENING IN THE NORTH...AND LEFT A SMALL
AREA OF SLIGHT CHANCE POPS IN THE FAR EAST AFTER 06Z. CONSIDERING
LIMITED MOISTURE AND QUICK NATURE OF THIS SYSTEM...ONLY ANTICIPATING
LIGHT SNOW ACCUMULATIONS...ABOUT AN INCH OR LESS.
TUESDAY-FRIDAY...REMAINING FORECAST LOOKS DRY WITH W/NW FLOW
DEVELOPING ACROSS WESTERN CONUS...AND DRY/STABLE AIR MASS IN PLACE.
BIGGEST QUESTION THROUGH THESE PERIODS WILL BE HOW QUICKLY SHALLOW
COLD AIR MASS MODERATES...AND WHAT TEMPS WILL DO IN RESPONSE TO WEAK
SHORTWAVE TROUGHS EMBEDDED WITHIN MEAN FLOW. FOR NOW EXPECT BELOW
NORMAL TEMPS TUESDAY AND NEAR NORMAL TEMPS WEDNESDAY. GUIDANCE STILL
INDICATING RISING H5 HEIGHTS H85 TEMPS TO ABOUT 10-12C BY
FRIDAY...WHEN I KEPT FORECAST OF MID 50S IN THE WEST. THIS MAY END
UP BEING TOO COOL CONSIDERING CONDITIONS ALOFT...HOWEVER THERE IS
ENOUGH UNCERTAINTY IN REGARDS TO BOUNDARY LAYER DIFFERENCES TO
KEEP ME FROM CHANGING TOO MUCH THIS FAR OUT.
DR
&&
.AVIATION...
1020 AM MST FRI JAN 13 2012
FOR THE 18Z TAFS...VFR CONDITIONS WILL CONTINUE THROUGH THE
PREVAILING PERIOD. LIGHT WINDS ARE EXPECTED TO BECOME GUSTY AFTER
19Z...HOWEVER...MODELS DIFFER IN INTENSITY. HAVE GONE MID RANGE
FOR WIND AND GUSTS...WILL MONITOR AND ADJUST IF NECESSARY. SURFACE
TROUGH WILL CONTINUE TO MOVE THROUGH THE AREA THIS AFTERNOON WITH
WINDS BECOMING LIGHT OVERNIGHT AND TOMORROW. A FEW MID LEVEL CLOUDS
WILL BE POSSIBLE AS THE UPPER LEVEL SYSTEM MOVES ACROSS THE
NORTHERN PLAINS.
PMM
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
1256 PM EST FRI JAN 13 2012
.SYNOPSIS...
LOW PRESSURE WILL MOVE EAST FROM THE GREAT LAKES AND DOWN THE
SAINT LAWRENCE RIVER VALLEY DRAGGING A COLD FRONT ACROSS THE
REGION THIS AFTERNOON. A SECOND COLD FRONT WILL MOVE THROUGH LATE
TONIGHT OR EARLY SATURDAY. ARCTIC HIGH PRESSURE WILL BUILD EAST
ACROSS THE REGION SATURDAY NIGHT THROUGH MONDAY. A COLD FRONT WILL
APPROACH FROM THE MIDWEST MONDAY NIGHT AND TUESDAY THEN EXIT THE
COAST EARLY WEDNESDAY. A RIDGE OF HIGH PRESSURE FOLLOWS FOR
WEDNESDAY. A WEAK CLIPPER SYSTEM WILL CROSS THE AREA LATE NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
1753Z UPDATE...
MORE ADVISORIES FOR FREEZING RAIN ARE SET TO EXPIRE OVER THE NEXT
HOUR. ATMOSPHERE WILL QUICKLY TRANSITION BEHIND THE STRONG FRONT.
DESPITE THE STRONG CAA...TEMPS MAY BRIEFLY JUMP UPWARDS INTO THE
30S IN MANY AREAS.
STRONG GUSTY WINDS AND ISOLD SQUALLS MAY OCCUR THROUGH THIS
EVENING...ESPECIALLY ACROSS THE HIGHER TERRAIN. HIGHEST WIND GUSTS
THIS AFTERNOON WILL BE OVER THE HILLTOWNS OF
MERRIMACK...ROCKINGHAM AND STRAFFORD COUNTIES...FOLLOWED BY GUSTY
WINDS ALL AREAS THIS EVENING.
1400Z UPDATE...
HAVE TAKEN A VERY CLOSE LOOK AT WIND FIELDS THIS MORNING AND USED
NEW MIXING TECHNIQUES IN THE GRIDS INVOLVING MIXING HEIGHT AND
WIND FIELDS FROM SEVERAL MODELS INCLUDING THE HRRR AND RUC. EXPECT
WIND GUSTS IN THE 35 TO 40 MPH RANGE OVER SOUTHERN NEW HAMPSHIRE
AND FAR SOUTHWEST MAINE TO DEVELOP DURING THE AFTERNOON HOURS.
WITH A FRESH GLAZE OF ICE ON THE TREES FROM THIS MORNINGS FREEZING
RAIN AND FREEZING DRIZZLE...EXPECT SOME TREE LIMBS TO BE DOWNED.
HAVE COORDINATED WITH NH ON THIS...AND HAVE CALLED OBSERVERS IN
THE AREA...WHICH SUGGESTS ABOUT A TENTH TO TWO TENTHS OF AN INCH
OF ICE HAS ACCUMULATED ON TREES. THE RESULT...WITH THE APPROACHING
WIND AND THE CURRENT ICING WILL BE SCATTERED POWER OUTAGES. WILL
CONTINUE TO MONITOR THIS CLOSELY AND WILL BE ISSUING AN SPS IN THE
NEXT HOUR FOR THIS POTENTIAL.
MINOR EDITS TO THE REST OF THE GRIDS...HOWEVER...HAVE LOWERED THE
MAX TEMPS DOWN A BIT. THIS HAS A BIG IMPACT ON THE MIXES LEVELS
THIS AFTERNOON. EXPECT TEMPS TO JUMP FOR ABOUT AN HOUR (UPWARDS)
AFTER THE FROPA...THEN HEAD RIGHT BACK DOWN.
WITH THE APPROACH OF THE OCCLUSION...FREEZING DRIZZLE AND FREEZING
RAIN SHOULD BE ENDING SHORTLY IN PORTIONS OF NH. HAVE ALLOWED SOME
OF THE ADVISORIES TO EXPIRE.
PREV DISC...
WILL UPDATE TO INPUT LATEST OBSERVED DATA. NO REAL CHANGES AT
THIS TIME. THE UPR LVL TROF AND SFC LOW ARE EXITING INTO THE
MARITIMES EARLY THIS MORNING WITH NORTHERLY WINDS IN ITS WAKE KEEP
TEMPS BELOW FREEZING JUST ABOUT EVERYWHERE ACROSS THE FCST AREA.
THE ONLY PLACES THAT MAY STILL BE AROUND FREEZING ARE ALONG THE
IMMEDIATE COASTLINE OVER THE MID COAST REGION OF MAINE.
A MUCH LARGER UPR LVL CUTOFF SYSTEM TO OUR SW WILL LIFT OUT TO
THE NE AND WEAKEN TDA AS IT FORCES A SFC LOW TO TRACK FROM THE ERN
GREAT LAKES DOWN THE ST LAWRENCE RIVER VALLEY TDA. A TRAILING CD
FNT WILL SWEEP FROM SW TO NE ACROSS THE FCST AREA LATE THIS
MORNING INTO THIS AFTERNOON. AHEAD OF THIS FNT CD AIR REMAINS AT
THE SFC WHILE WARMER AIR CONTINUES TO MOVE IN ALOFT. AN AREA OF
PRCP MOVES IN WITH THE UPR LVL AND SFC SYSTEMS...AND IS ALREADY
SHOWING UP ON THE RADAR MOSAIC LOOP WITH PRCP POISED TO MOVE INTO
OUR MOST SW ZONES AT THIS TIME.
PRCP WILL BE MOSTLY LGT FZRA THOUGH SOME IP OR EVEN SOME WET SN
PSBL ACROSS THE MORE NRN ZONES. COULD SEE SOME -RA ALONG THE MID
COAST REGION. WITH ACCUMULATING FZRA THRU THE MORNING AND INTO THE
AFTERNOON OVER MORE NRN AND ERN ZONES WILL CONT A FREEZING RAIN
ADVISORY. THERE COULD BE OTHER PRCP TYPES WITH THIS EVENT...
ESPECIALLY ACROSS THE N/MT ZONES BUT THE MAIN THREAT WILL BE FZRA
AND WANT TO HIGHLIGHT THAT.
AS THE FNT MOVES THRU GUSTY SW WINDS SET UP WHICH MIX OUT THE
TEMP SOUNDING WHICH SHOULD WRM UP THE SFC BUT AT THE SAME TIME
COLDER AIR MOVES IN ALOFT. THIS WILL FORCE PRCP OVER TO -SHSN OR
-SHRA CHANGING OVER TO -SHSN WITH SOME ACCUMULATION PSBL ACROSS
THE N/MT ZONES. GENERALLY USED GFS40 AND A BLEND OF MAV/MET MOS
ALONG WITH RFC QPF FOR THE NEAR TERM FCST.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A SECOND CD FNT MOVES THRU LATER TNGT AND OUT TO SEA SATURDAY
MORNING. SHSN AND SOME ACCUMULATION, MAINLY N/MT ZONES, PSBL WITH
THIS FNT WITH DRYER AND MUCH COLDER AIR MOVING IN ON GUSTY NW
WINDS BEHIND THE FNT FOR LATE TNGT AND SATURDAY. GENERALLY USED
GFS40 AND A BLEND OF MAV/MET MOS ALONG WITH RFC QPF FOR THE SHORT
TERM FCST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AN UPPER TROUGH AND BELOW NORMAL TEMPERATURES WILL DOMINATE ACROSS
THE NORTHEAST FOR MUCH OF THE PERIOD. A BRIEF RESPITE TUESDAY...WITH
RIDGING AND WEST-SOUTHWEST FLOW TO PROVIDE A ONE DAY WARM UP AND
WELL ABOVE NORMAL TEMPERATURES. WE BEGIN THE PERIOD WITH ARCTIC
HIGH PRESSURE BUILDING EAST ACROSS THE FORECAST AREA SATURDAY
NIGHT THROUGH MONDAY WITH WELL BELOW NORMAL TEMPERATURES. A COLD
FRONT APPROACHES FROM THE MIDWEST MONDAY NIGHT AND TUESDAY PRECEDED
BY A MILDER SOUTHWEST FLOW. THE COLD FRONT WILL EXIT THE COAST
EARLY WEDNESDAY FOLLOWED BY A FRESH SHOT OF ARCTIC AIR. A WEAK
CLIPPER SYSTEM WILL CROSS THE REGION THURSDAY INTO FRIDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /TODAY THROUGH SATURDAY/...VARIABLE CONDITIONS WITH
MOSTLY IFR TO LIFR CIG/VSBY ALONG WITH MIXED, THOUGH MOSTLY FZRA,
THIS MORNING INTO THIS AFTERNOON. IMPROVING CONDITIONS THIS
AFTERNOON BUT WITH GUSTY W SW WINDS SETTING UP BEHIND A CD FNT. A
SECOND CD FNT MAY BRING SOME -SHSN TO MAINLY THE N/MT AREAS TNGT
BUT WITH IMPROVING CONDITIONS FOR MOST TAF SITES. THE IMPROVING
TREND WILL CONT ON SATURDAY.
LONG TERM...
MON PM - TUE...AREAS OF MVFR POSSIBLE IN RAIN AND SNOW SHOWERS.
TUE...SW SFC WIND MAY GUST TO 25 KT.
&&
.MARINE...
SHORT TERM /TODAY THROUGH SATURDAY/...WILL CONT THE GLW THRU TNGT.
WINDS WILL BELOW GALE FORCE THIS MORNING BUT PICK UP LATER ON AS A
CD FNT MOVES THRU AND A STRONG SW PRES GRADIENT SETS UP AND
CONTINUES INTO TNGT UNTIL A CD FNT APPROACHES THE WATERS TOWARD
DAYBREAK. COULD SEE A FEW GUSTS INTO STORM FORCE...AROUND 50 KT
LATER TDA AND TNGT. WINDS SLOWLY LET UP SATURDAY AS THE PRES
GRADIENT LETS UP...BUT A CD NW FLOW OVER THE WARMER WATER WILL
STILL KEEP SOME GUSTINESS AROUND.
LONG TERM...
MON PM - TUE...GALE FORCE WINDS ARE POSSIBLE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...GALE WARNING UNTIL 7 AM EST SATURDAY FOR ANZ150>154.
&&
$$
JC
AREA FORECAST DISCUSSION
NWS GRAY ME
1131 AM EST FRI JAN 13 2012
.SYNOPSIS...
LOW PRESSURE WILL MOVE EAST FROM THE GREAT LAKES AND DOWN THE
SAINT LAWRENCE RIVER VALLEY DRAGGING A COLD FRONT ACROSS THE
REGION THIS AFTERNOON. A SECOND COLD FRONT WILL MOVE THROUGH LATE
TONIGHT OR EARLY SATURDAY. ARCTIC HIGH PRESSURE WILL BUILD EAST
ACROSS THE REGION SATURDAY NIGHT THROUGH MONDAY. A COLD FRONT WILL
APPROACH FROM THE MIDWEST MONDAY NIGHT AND TUESDAY THEN EXIT THE
COAST EARLY WEDNESDAY. A RIDGE OF HIGH PRESSURE FOLLOWS FOR
WEDNESDAY. A WEAK CLIPPER SYSTEM WILL CROSS THE AREA LATE NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...
HAVE TAKEN A VERY CLOSE LOOK AT WIND FIELDS THIS MORNING AND USED
NEW MIXING TECHNIQUES IN THE GRIDS INVOLVING MIXING HEIGHT AND
WIND FIELDS FROM SEVERAL MODELS INCLUDING THE HRRR AND RUC. EXPECT
WIND GUSTS IN THE 35 TO 40 MPH RANGE OVER SOUTHERN NEW HAMPSHIRE
AND FAR SOUTHWEST MAINE TO DEVELOP DURING THE AFTERNOON HOURS.
WITH A FRESH GLAZE OF ICE ON THE TREES FROM THIS MORNINGS FREEZING
RAIN AND FREEZING DRIZZLE...EXPECT SOME TREE LIMBS TO BE DOWNED.
HAVE COORDINATED WITH NH ON THIS...AND HAVE CALLED OBSERVERS IN
THE AREA...WHICH SUGGESTS ABOUT A TENTH TO TWO TENTHS OF AN INCH
OF ICE HAS ACCUMULATED ON TREES. THE RESULT...WITH THE APPROACHING
WIND AND THE CURRENT ICING WILL BE SCATTERED POWER OUTAGES. WILL
CONTINUE TO MONITOR THIS CLOSELY AND WILL BE ISSUING AN SPS IN THE
NEXT HOUR FOR THIS POTENTIAL.
MINOR EDITS TO THE REST OF THE GRIDS...HOWEVER...HAVE LOWERED THE
MAX TEMPS DOWN A BIT. THIS HAS A BIG IMPACT ON THE MIXES LEVELS
THIS AFTERNOON. EXPECT TEMPS TO JUMP FOR ABOUT AN HOUR (UPWARDS)
AFTER THE FROPA...THEN HEAD RIGHT BACK DOWN.
WITH THE APPROACH OF THE OCCLUSION...FREEZING DRIZZLE AND FREEZING
RAIN SHOULD BE ENDING SHORTLY IN PORTIONS OF NH. HAVE ALLOWED SOME
OF THE ADVISORIES TO EXPIRE.
PREV DISC...
WILL UPDATE TO INPUT LATEST OBSERVED DATA. NO REAL CHANGES AT
THIS TIME. THE UPR LVL TROF AND SFC LOW ARE EXITING INTO THE
MARITIMES EARLY THIS MORNING WITH NORTHERLY WINDS IN ITS WAKE KEEP
TEMPS BELOW FREEZING JUST ABOUT EVERYWHERE ACROSS THE FCST AREA.
THE ONLY PLACES THAT MAY STILL BE AROUND FREEZING ARE ALONG THE
IMMEDIATE COASTLINE OVER THE MID COAST REGION OF MAINE.
A MUCH LARGER UPR LVL CUTOFF SYSTEM TO OUR SW WILL LIFT OUT TO
THE NE AND WEAKEN TDA AS IT FORCES A SFC LOW TO TRACK FROM THE ERN
GREAT LAKES DOWN THE ST LAWRENCE RIVER VALLEY TDA. A TRAILING CD
FNT WILL SWEEP FROM SW TO NE ACROSS THE FCST AREA LATE THIS
MORNING INTO THIS AFTERNOON. AHEAD OF THIS FNT CD AIR REMAINS AT
THE SFC WHILE WARMER AIR CONTINUES TO MOVE IN ALOFT. AN AREA OF
PRCP MOVES IN WITH THE UPR LVL AND SFC SYSTEMS...AND IS ALREADY
SHOWING UP ON THE RADAR MOSAIC LOOP WITH PRCP POISED TO MOVE INTO
OUR MOST SW ZONES AT THIS TIME.
PRCP WILL BE MOSTLY LGT FZRA THOUGH SOME IP OR EVEN SOME WET SN
PSBL ACROSS THE MORE NRN ZONES. COULD SEE SOME -RA ALONG THE MID
COAST REGION. WITH ACCUMULATING FZRA THRU THE MORNING AND INTO THE
AFTERNOON OVER MORE NRN AND ERN ZONES WILL CONT A FREEZING RAIN
ADVISORY. THERE COULD BE OTHER PRCP TYPES WITH THIS EVENT...
ESPECIALLY ACROSS THE N/MT ZONES BUT THE MAIN THREAT WILL BE FZRA
AND WANT TO HIGHLIGHT THAT.
AS THE FNT MOVES THRU GUSTY SW WINDS SET UP WHICH MIX OUT THE
TEMP SOUNDING WHICH SHOULD WRM UP THE SFC BUT AT THE SAME TIME
COLDER AIR MOVES IN ALOFT. THIS WILL FORCE PRCP OVER TO -SHSN OR
-SHRA CHANGING OVER TO -SHSN WITH SOME ACCUMULATION PSBL ACROSS
THE N/MT ZONES. GENERALLY USED GFS40 AND A BLEND OF MAV/MET MOS
ALONG WITH RFC QPF FOR THE NEAR TERM FCST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
A SECOND CD FNT MOVES THRU LATER TNGT AND OUT TO SEA SATURDAY
MORNING. SHSN AND SOME ACCUMULATION, MAINLY N/MT ZONES, PSBL WITH
THIS FNT WITH DRYER AND MUCH COLDER AIR MOVING IN ON GUSTY NW
WINDS BEHIND THE FNT FOR LATE TNGT AND SATURDAY. GENERALLY USED
GFS40 AND A BLEND OF MAV/MET MOS ALONG WITH RFC QPF FOR THE SHORT
TERM FCST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AN UPPER TROUGH AND BELOW NORMAL TEMPERATURES WILL DOMINATE ACROSS
THE NORTHEAST FOR MUCH OF THE PERIOD. A BRIEF RESPITE TUESDAY...WITH
RIDGING AND WEST-SOUTHWEST FLOW TO PROVIDE A ONE DAY WARM UP AND
WELL ABOVE NORMAL TEMPERATURES. WE BEGIN THE PERIOD WITH ARCTIC
HIGH PRESSURE BUILDING EAST ACROSS THE FORECAST AREA SATURDAY
NIGHT THROUGH MONDAY WITH WELL BELOW NORMAL TEMPERATURES. A COLD
FRONT APPROACHES FROM THE MIDWEST MONDAY NIGHT AND TUESDAY PRECEDED
BY A MILDER SOUTHWEST FLOW. THE COLD FRONT WILL EXIT THE COAST
EARLY WEDNESDAY FOLLOWED BY A FRESH SHOT OF ARCTIC AIR. A WEAK
CLIPPER SYSTEM WILL CROSS THE REGION THURSDAY INTO FRIDAY.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
SHORT TERM /TODAY THROUGH SATURDAY/...VARIABLE CONDITIONS WITH
MOSTLY IFR TO LIFR CIG/VSBY ALONG WITH MIXED, THOUGH MOSTLY FZRA,
THIS MORNING INTO THIS AFTERNOON. IMPROVING CONDITIONS THIS
AFTERNOON BUT WITH GUSTY W SW WINDS SETTING UP BEHIND A CD FNT. A
SECOND CD FNT MAY BRING SOME -SHSN TO MAINLY THE N/MT AREAS TNGT
BUT WITH IMPROVING CONDITIONS FOR MOST TAF SITES. THE IMPROVING
TREND WILL CONT ON SATURDAY.
LONG TERM...
MON PM - TUE...AREAS OF MVFR POSSIBLE IN RAIN AND SNOW SHOWERS.
TUE...SW SFC WIND MAY GUST TO 25 KT.
&&
.MARINE...
SHORT TERM /TODAY THROUGH SATURDAY/...WILL CONT THE GLW THRU TNGT.
WINDS WILL BELOW GALE FORCE THIS MORNING BUT PICK UP LATER ON AS A
CD FNT MOVES THRU AND A STRONG SW PRES GRADIENT SETS UP AND
CONTINUES INTO TNGT UNTIL A CD FNT APPROACHES THE WATERS TOWARD
DAYBREAK. COULD SEE A FEW GUSTS INTO STORM FORCE...AROUND 50 KT
LATER TDA AND TNGT. WINDS SLOWLY LET UP SATURDAY AS THE PRES
GRADIENT LETS UP...BUT A CD NW FLOW OVER THE WARMER WATER WILL
STILL KEEP SOME GUSTINESS AROUND.
LONG TERM...
MON PM - TUE...GALE FORCE WINDS ARE POSSIBLE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...FREEZING RAIN ADVISORY UNTIL 11 AM EST THIS MORNING FOR MEZ018-
023.
FREEZING RAIN ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MEZ007>009-012>014-019>022-024>028.
NH...FREEZING RAIN ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NHZ005>010-013-014.
FREEZING RAIN ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
NHZ001>004.
MARINE...GALE WARNING UNTIL 7 AM EST SATURDAY FOR ANZ150>154.
&&
$$
JC
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1145 PM EST THU JAN 12 2012
.SYNOPSIS.../ISSUED AT 350 PM/
DEEP LOW PRESSURE WILL SLOWLY CREEP NORTHWARD INTO LAKE HURON
TONIGHT. SNOW WILL SPREAD OVER ALL OF NORTHERN MICHIGAN THROUGH
TONIGHT...AND THEN TAPER OFF FRIDAY. INCREASING NORTH TO NORTHEAST
WINDS...WILL TRANSPORT MUCH COLDER TEMPERATURES INTO THE REGION...
AND ALSO LEAD TO CONSIDERABLE BLOWING AND DRIFTING SNOW. A FEW LIGHT
SNOW SHOWERS AND FLURRIES...WILL LINGER INTO SATURDAY AND SUNDAY...
BUT WITH NO ADDITIONAL ACCUMULATION. TEMPERATURES WILL TURN MILDER
EARLY NEXT WEEK...AS THE NEXT ORGANIZED SYSTEM MOVES THROUGH.
HALBLAUB
&&
.SHORT TERM.../ISSUED AT 922 PM/...TONIGHT
UPDATE: GOING FCST IS WELL ON TRACK AT THIS POINT...WITH A WIDE
SWATH OF MAINLY LIGHT TO OCCASIONALLY MODERATE SNOW PINWHEELING
OVERHEAD. SAID SNOW SHIELD IS CURRENTLY BEING DRIVEN BY ELONGATED
AXIS OF WARM ADVECTION ASCENT WITHIN PRONOUNCED TROWAL FEATURE
WRAPPING NORTH OF CLOSED 850-700MB LOWS NEARING SAGINAW BAY. ALSO
HELPING IS INCREASED DEFORMATION DYNAMICS DEVELOPING OVERHEAD...
WHICH SHOULD EASILY MAINTAIN CURRENT SNOW SHIELD MUCH OF THE REST OF
THE NIGHT AS TROWAL FORCING WEAKENS. LATEST RUC FCST RAOBS COMBINED
WITH 7-8PM REPORTS (THANKS TO ALL THE SPOTTERS!) SHOW RATIOS ARE
NOTHING SPECIAL...GENERALLY AROUND 10/12 TO 1...SAVE FOR EARLIER
BETTER RATIOS ACROSS THE HIGHER TERRAIN...IN LINE WITH PROGGED
BETTER LIFT THROUGH THE DGZ...WHICH HAS SINCE FADED. SNOWFALL TOTALS
THUS FAR ARE GENERALLY 1 TO 3 INCHES ACROSS MUCH OF NORTHERN
LOWER...MAINLY LESS THAN AN INCH NORTH OF THE STRAITS...WHERE
EARLIER WEDGE OF LOW LEVEL DRY AIR HELD SNOW AT BAY UNTIL ABOUT 00Z.
HEADING THROUGH THE NIGHT...GOING HEADLINES LOOK JUST FINE...THOUGH
STARTING TO FEEL THE CURRENT WARNING MAY BE A BIT OF AN OVERKILL.
STILL...WILL GIVE IT A CHANCE WITH SOME POTENTIAL FOR LAKE
ENHANCEMENT TO KICK IN AFTER 06Z WITH INCREASING INFLUX OF MUCH
COLDER AIR (H85 TEMPS TUMBLING DOWN TOWARD -12C). IN GENERAL...HAVE
LOWERED CURRENT FCST AMOUNTS JUST A TAD IN MANY AREAS THROUGH THE
NIGHT...ESPECIALLY CLOSE TO SAGINAW BAY WHERE INCOMING DRY SLOT MAY
MAKE AN APPEARANCE. STILL LOOKING LIKE ANOTHER GENERAL 2 TO 4 INCHES
WILL FALL OVERNIGHT PER RADAR EXTRAPOLATION AND EXPECTED ONLY MODEST
RATIOS OF 15 TO 1 AT BEST...WELL IN LINE WITH CURRENT ADVISORY
(AGAIN...THE WARNING MAY BE A BIT OVERDONE) AND EARLIER
EXPECTATIONS. HAVE REWORKED DIURNAL TEMPS TO SOME DEGREE TO SHOW A
SLOWER COOLING TREND (TEMPS STILL IN THE LOWER 30S IN MANY AREAS)...
THOUGH ONCE COLD ADVECTION KICKS IN TOWARD 06Z...READINGS WILL
QUICKLY TANK THROUGH THE TEENS AND 20S IN ALL AREAS.
LAWRENCE
EARLIER EXCELLENT DISCUSSION FOLLOWS:
WINTER EVENT PLUGGING ALONG JUST FINE. LOW PRESSURE CONTINUES TO
ORGANIZE AND STRENGTHEN OVER THE THUMB OF LOWER MICHIGAN...A
FAVORABLE LOCATION FOR DECENT SNOW AMOUNTS FOR MANISTEE THROUGH
GAYLORD AND ROGERS CITY IN NRN LOWER. (AXIS OF BEST SYNOPTIC
SNOWS). THE PARENT UPPER TROUGH WHICH CLOSED OFF...IS SWEEPING
ACROSS SRN IL ATTM...WHILE +100KT UPPER JET AND LEFT EXIT DYNAMICS
AND THE DEEP LAYER -DIVQ IS AIDING THE AREAS THAT WERE ALREADY
SNOWING...WHILE ALSO ERODING THE WEDGE OF DRY AIR ACROSS NW LOWER.
SNOWS ARE STARTING TO BREAK OUT THERE. IN ADDITION SOUNDING DATA
SUPPORTING LARGE DENDRITES RIGHT NOW WITH LIFT MAXIMIZING IN THE
DGZ. FOG ERODES QUICKLY WITH ONSET OF THE SNOWS. STILL QUIET IN
EASTERN UPPER. ONLY A FEW SPOTS HAVE RAIN MIXED IN WITH THE
SNOW...PRIMARILY ON THE COASTS...AND WHERE THE SNOW REMAINS LIGHT.
EVEN NE LOWER NEAR THE BAY HAS BEEN PRIMARILY SNOW...DUE TO BETTER
PRECIPITATION INTENSITY.
THROUGH THE NIGHT...MODEST TO STRONG FORCING AND JET DYNAMICS
CONTINUE TO OVERSPREAD TROWAL THROUGH THE EVENING...YET THE LIFT
MAXIMIZED IN THE DGZ WILL FALL OFF EARLY THIS EVENING WHILE THE
LOW PRESSURE SHIFTS INTO GEORGIAN BAY. THERE IS LITTLE TO NO HELP
WITH THE LAKES THROUGH THIS TIME...SO PURELY A SYNOPTIC SNOWFALL.
THIS IS NOT A PROBLEM IN PICKING UP A SOLID 3 TO 5 INCHES THROUGH
THIS EVENING IN NRN LOWER FOR AREAS MAINLY ALONG AND WEST OF I75.
AS THE LOW PRESSURE PULLS OFF TO THE EAST...THE STRONGER DYNAMICS
EXIT AND WE TURN TO MORE OF A LAKE ENHANCED SNOWFALL WITHIN
DEFORMATION ZONE ALOFT. THE COLDEST ADVECTION WILL BE WITHIN
STRENGTHENING LOW LEVEL NORTH TO NNW FLOW ACROSS NW LOWER.
INVERSION HEIGHTS NEVER REALLY GET PAST 4500 FEET...BUT CAN SEE 2
INCHES OF LAKE HELP ADDING TO ANOTHER INCH OR SO FROM DEFORMATION
SNOWS. THUS...IN THE WARNING COUNTIES...CAN SEE UP TO 6 INCHES
FALLING THROUGH TONIGHT. THE CYCLONIC CONVERGENCE IS SO GOOD THAT
WINDS ARE MORE NNE OUT OF ONTARIO...WHICH VIRTUALLY SHUTS OFF
EASTERN UPPER FROM ANY LAKE HELP (NO FETCH). ANYWAYS...SYNOPTIC
DEFORMATION SNOWS RANGING FROM AN INCH SW TO 2 INCHES DRUMMOND
ISLAND OVERNIGHT WILL RESULT IN SNOWFALL TOTALS OF 4 TO 6 INCHES
FOR MOST OF NRN MICHIGAN THROUGH TONIGHT FOR SOLID ADVISORY
CRITERIA. DID EXPAND ADVISORIES TO INCLUDE ROSCOMMON COUNTY TO
ALPENA COUNTY. THE LEAST SNOW AMOUNTS WILL FALL IN WESTERN
CHIP/MACK OF EASTERN UPPER AWAY FROM NEST DYNAMICS AND
DEFORMATION/LAKE EFFECT...AS WELL AS COUNTIES NEAR SAG BAY...WHERE
ALSO THERE WILL BE A BIT OF DRYING ALOFT (DRY SLOT JUST SOUTHEAST
OF THERE). CAN SEE 1-3 INCHES IN THESE AREAS. WILL ALSO BE SOME
AREAS OF BLOWING SNOW DEVELOPING THROUGH THE NIGHT AS TIGHTER
PRESSURE GRADIENT SLIDES IN ON BACKSIDE OF THE DEPARTING LOW. AT
NIGHT...WORST OF THE BLOWING SNOW WILL BE ALONG THE LAKE MICHIGAN
COAST AND EVEN WHITEFISH BAY (IF THE SNOW FALLS MORE DECENTLY THAN
CURRENT THINKING FOR THERE). THE COLD ADVECTION WILL RESULT IN
LOWS FALLING INTO THE TEENS NORTH TO THE LOWER 20S SOUTH.
SMD
&&
.LONG TERM.../ISSUED AT 350 PM/...FRIDAY AND BEYOND
FRIDAY...DEFORMATION SYNOPTIC SNOWS WILL BE ENDING IN THE MORNING
AS LOW PRESSURE CONTINUES TO LIFT FURTHER EAST OF US. THE DEEPER
MOISTURE WILL BE ON THE WAY OUT AS WELL...HOWEVER THERE WILL BE A
PERIOD OF TIME WHERE THE NNW LAKE EFFECT AREAS WILL SEE MODERATE
SNOWS PERSISTING INTO THE MORNING. THUS ALL WARNINGS/ADVISORIES
WILL HOLD THROUGH THE DAY. DURING THE AFTERNOON HOWEVER...THERE
WILL BE SOME DRY AIR DIVING DOWN FROM THE NORTH. THERE IS STILL
GOOD CYCLONIC CONVERGENCE WHILE THE DRY AIR ARRIVES...AND WITH
LAKE EFFECT SUSTAINING ITSELF LONGER THAN TYPICALLY
EXPECTED...WILL KEEP SNOW SHOWERS GOING SOUTH AND WEST OF GTV BAY
THROUGH THE AFTERNOON WITH TOTAL ACCUMS OF ANOTHER 1 TO 3 INCHES.
THIS IS NOT TRUE FOR EASTERN UPPER...WHERE WINDS REMAIN OUT OF THE
NORTH. MAYBE FAR WESTERN CHIP/MACK CAN SEE SOME LIGHT SNOW
SHOWERS...BUT DOWNSLOPING FLOW FROM ONTARIO WILL LIKELY TAKE AREAS
ALONG AND EAST OF -I75 THERE...PARTLY CLOUDY (MOSTLY SUNNY?). THE
DEPARTING DEFORMATION/DEEPER MOISTURE WILL GIVE UP TO ANOTHER INCH
FOR ALL OTHER AREAS. TEMPERATURES WILL REMAIN IN THE TEENS NORTH
TO LOWER 20S SOUTH THROUGH THE DAY..AS THEY EITHER BE STEADY OR
SLOWLY FALLING IN STRONG COLD ADVECTION. WINTER IS HERE.
LATER PERIODS...
DISCUSSION...QUICK INTRUSION OF MODIFIED ARCTIC AIR LATE
THIS WEEK WILL BE JUST THAT...QUICK...WITH WELL AGREED UPON MODEL
PROGS SUGGESTING A RAPID TRANSITION TO QUASI-ZONAL FLOW REGIME BY
LATER THIS WEEKEND...TRENDING TOWARD DEEPENING WESTERN TROUGHING
EARLY NEXT WEEK. LARGE SCALE INDICES/FEATURES SUPPORT SUCH...WITH
FAR EAST DISPLACED ATLANTIC BLOCKING (MAINTENANCE OF WEAKLY
POSITIVE NAO) AND BUILDING ALEUTIAN ISLANDS/BERING SEA RIDGING
(ALLOWING ENERGY TO CUT BACK SOUTHWEST ON ITS DOWNSTREAM
SIDE...DEVELOPING THE WESTERN TROUGH). PATTERN ALSO EXPECTED TO BE
A RATHER ACTIVE ONE...BOTH WITH PRECIPITATION AND TEMPERATURE
TRENDS...AS ENERGY EJECTING OUT OF THIS WESTERN TROUGH INTERACTS
WITH TIGHTENING NORTHERN CONUS BAROCLINIC ZONE. FORECAST CONCERNS
INITIALLY CENTER ON LINGERING LIGHT LAKE INDUCED SNOW POTENTIAL IN
RETREATING COLD AIRMASS THIS WEEKEND...WITH LATER CONCERNS FOCUSED
ON THE TEMPERATURE ROLLER COASTER RIDE AND POSSIBLE EARLY WEEK
STORM SYSTEM.
SYNOPTIC EFFECTS OF CURRENT WINTER STORM WILL END QUICKLY FRIDAY
EVENING...LEAVING BEHIND MORE OF A PURE LAKE INDUCED SIGNATURE FOR
SNOW GENERATION. REMNANT SYNOPTIC MOISTURE SHOULD CONTINUE TO HELP
GENERATE LAKE INDUCED SNOWS IN FAVORED NNW FLOW AREAS EARLY FRIDAY
EVENING...WITH QUICKLY WANING INTENSITY OVERNIGHT AS MOISTURE
DEPARTS AND INVERSION LEVELS STAY AROUND 850MBS. SIMPLE OVER-WATER
INSTABILITY (DELTA T/S IN THE LOWER 20S) AND IN-CLOUD OMEGA CENTERED
IN THE DGZ FAVOR AT LEAST SOME MINOR ACCUMULATIONS THROUGH THE
OVERNIGHT...WITH PERHAPS AN INCH TO INCH AND A HALF FOCUSED JUST
WEST AND SOUTHWEST OF TRAVERSE CITY. INCREASINGLY WEAK FLOW LIKELY
TO LEAD TO SOME LAND BREEZE DISRUPTION BY SATURDAY MORNING...
FOCUSING "BEST" SNOWS TO ALONG THE LAKE MICHIGAN SHORELINE. SAME
LIGHT FLOW SUPPORTS GOOD NORTHEAST DRAINAGE FLOW OFF THE ONTARIO
PLATEAU NORTH OF THE SOO...WITH SHOULD PUSH LAKE SUPERIOR SNOWS WEST
OF WHITEFISH POINT BY EARLY SATURDAY MORNING (FRIDAY EVENING NORTH
TO NORTHEAST FLOW ALSO NOT CONDUCIVE FOR HEAVY LAKE SNOWS). HAVE
GONE AHEAD A CUT SNOW COVERAGE AND AMOUNTS SIGNIFICANTLY FRIDAY
NIGHT ACROSS EASTERN UPPER (JUST TRACE AMOUNTS). WEAK LAKE SNOWS TO
CONTINUE INTO SATURDAY...ALTHOUGH LIGHT WINDS SURE TO PLAY HAVOC
WITH EXACT PLACEMENT OF ACTIVITY. GROWING EVIDENCE OF SOME LAKE
INDUCED MESOLOW FORMATION OVER NORTHERN LAKE MICHIGAN/NORTHERN GRAND
TRAVERSE BAY LATE FRIDAY NIGHT INTO SATURDAY MORNING...WITH FOCUSED
CONVERGENCE CONTINUING THE LIGHT SNOW SHOWER THREAT ALONG THE
IMMEDIATE LAKE MICHIGAN SHORELINE. SNOW AMOUNTS SHOULD BE WELL UNDER
AN INCH...UNLESS CONVERGENCE AXIS GETS TOO OUT OF HAND (SURE HAVE
SEEN THAT BEFORE). TEMPERATURES DEPENDENT ON CLOUD COVERAGE AND SNOW
ACTIVITY...WITH PATTERN RECOGNITION OF GOOD DRAINAGE FLOW
DEVELOPMENT SUPPORTING GUIDANCE TRENDS OF DROPPING READINGS WELL
BELOW ZERO OVER EAST SECTIONS OF EASTERN UPPER...AND NEAR ZERO
READING IN THE FAVORED COLD LOCATIONS OF NORTHEAST LOWER FOR FRIDAY
NIGHT. ONE OF THE COLDEST AIR MASSES OF THE SEASON FOR SATURDAY...
WITH DAYTIME HIGHS GENERALLY STUCK IN THE TEENS.
NEBULOUS FORECAST CONTINUES THROUGH THE REMAINDER OF THE
WEEKEND...WITH GUIDANCE STRUGGLING WITH WEAK CLIPPER TYPE SYSTEM
SLATED TO CROSS THROUGH THE REGION. GFS THE MOST AGGRESSIVE BY
FAR...BRING A DECENT SURFACE LOW THROUGH THE STRAITS SUNDAY MORNING.
OTHER GUIDANCE NOT NEARLY SO AMBITIOUS...WITH JUST A DIFFUSE
RELAXATION IN THE PRESSURE FIELDS AND MUCH LESS MOISTURE. MID LEVEL
SUPPORT SIDES WITH THE LESS AGGRESSIVE SCENARIOS (AS DOES
MULTI-PERIOD TRENDS)...WHICH INHERITED FORECAST ALREADY SUPPORTS.
LAKE SNOWS MAY GET SOMEWHAT OF A BOOST TOWARDS SUNDAY MORNING...WITH
INCREASING MOISTURE PROGS AND DEVELOPING LIGHT SOUTHWEST FLOW
HELPING THE MOISTURE FLUX FROM THE WATERS. COMBINE THIS WITH
TEMPERATURES STILL PLENTY COLD ENOUGH (850MB TEMPERATURES IN THE
NEGATIVE TEENS)...AND AT LEAST SOME LIGHT SNOW SHOWERS SHOULD MOVE
INTO MACKINAC COUNTY IN FAVORED SOUTHWEST FLOW AREAS.
OTHERWISE...WILL KEEP OTHER AREAS DRY.
AS MENTIONED EARLIER...A RATHER ACTIVITY PATTERN UNFOLDING FOR NEXT
WEEK AS ENERGY DIGS OUT WEST AND BAROCLINIC ZONE TIGHTENS ACROSS THE
NORTHERN CONUS. INITIAL WARM SURGE EXPECTED TO OVERSPREAD NORTHERN
MICHIGAN QUICKLY MONDAY AS SOUTHWEST FLOW STRENGTHENS ON DOWNSTREAM
SIDE OF DEPARTING HIGH PRESSURE. SUBTLE WEAK LEAD WAVE AND MOISTURE
FLUX IN WAA REGIME MAY KICK OFF A LIGHT WINTRY MIX MONDAY (RAIN/SNOW
SOUTH...ALL SNOW NORTH). BIGGER CONCERN IS POSSIBLE LOW DEVELOPMENT
AND INTENSE FGEN SIGNATURE ALONG SLOWING COLD FRONT AS PRIMARY WAVE
EJECTS OUT OF THE PLAINS MONDAY NIGHT INTO EARLY TUESDAY. PLENTY OF
HIGH RES GUIDANCE AND LOW RES ENSEMBLE SUPPORT FOR THE
ABOVE...ALTHOUGH WITH PLENTY OF UNCERTAINTY ON THE TRACK OF THE
SURFACE LOW. WILL KEEP HIGH CHANCE SNOW WORDING MONDAY NIGHT INTO
TUESDAY TO ACCOUNT FOR REMAINING UNCERTAINTY. WILL SAY SOME OF THE
GFS ENSEMBLES ARE AWFULLY STRONG WITH THIS SYSTEM (SUB 990MBS)...AND
WITH THE TENDENCY FOR THESE PACIFIC WAVES TO END UP STRONGER THAN
INITIALLY PROGGED DOES LEND AT LEAST SOME CREDENCE TO THESE STRONGER
SOLUTIONS. DEFINITELY SOMETHING TO WATCH WITH MOUNTING EVIDENCE OF A
GREAT WESTERN GULF OF MEXICO MOISTURE CONNECTION. WILL CONTINUE TO
HIGHLIGHT THIS POTENTIAL IN THE AFTERNOON RENDITION OF THE HAZARDOUS
WEATHER OUTLOOK. A GLANCING BLOW OF VERY COLD ARCTIC AIR TO FOLLOW
THIS SYSTEM TUESDAY NIGHT INTO THURSDAY...WITH 850MB TEMPERATURES
FALLING TO NEAR -20C. MORE THAN COLD ENOUGH TO START THE LAKE
MACHINE...ESPECIALLY IN FAVORED NORTHWEST FLOW AREAS. HIGH
TEMPERATURES BACK IN THE TEENS BOTH WEDNESDAY AND THURSDAY.
MSB
&&
.MARINE.../ISSUED AT 350 PM/
WINDS WILL BE INCREASING THROUGH TONIGHT FROM WEST TO EAST ACROSS
THE GREAT LAKES AS TIGHTER PRESSURE GRADIENT SLIDES IN BEHIND A
DEPARTING LOW PRESSURE SYSTEM THAT WILL BE PRODUCING MODERATE TO
HEAVY SNOWS ACROSS THE REGION. GALES STILL LOOK REAL GOOD FOR
SLEEPING BEAR POINT SOUTHWARD...BUT REMAIN JUST SHY ALL OTHER
AREAS INTO TOMORROW. THUS...ALL HEADLINES WILL HOLD AS IS. WAVE
ACTION WILL CONTINUE TO BE AN ISSUE INTO FRIDAY NIGHT.
SMD
NORTHWEST WINDS EXPECTED TO SUBSIDE RATHER QUICKLY FRIDAY
EVENING AS HIGH PRESSURE BUILDS INTO THE AREA. LIGHT WINDS WILL
CONTINUE THROUGH AT LEAST SATURDAY NIGHT...WITH SOUTHWEST FLOW
BEGINNING TO STRENGTHEN BY LATER SUNDAY. SOUTH WINDS...AT TIMES
GUSTY...WILL CONTINUE INTO EARLY NEXT WORK WEEK AHEAD OF AN
APPROACHING COLD FRONT.
MSB
&&
.AVIATION.../ISSUED AT 1145 PM/...VALID FOR 06Z TAFS
WIDESPREAD LIGHT TO OCCASIONALLY MODERATE SNOW WITH IFR
CONDITIONS WILL CONTINUE AT ALL TERMINAL SITES THE REMAINDER OF
THE NIGHT...ENDING FROM WEST TO EAST THROUGH THE MORNING AS UPPER
LEVEL FORCING WANES AND MOISTURE DECREASES. EXPECT SOME
DEVELOPMENT OF LAKE EFFECT SNOW SHOWERS AS WINDS SETTLE IN FROM
THE NORTH/NORTHWEST...FAVORING PRIMARILY TVC AND MBL FOR THE
LOWEST CEILINGS AND BRIEF INTERLUDES OF LOWER VISBYS. WINDS WILL
BECOME GUSTY FOR ALL LOCATIONS THROUGH THE NIGHT...WITH THE
POTENTIAL FOR SOME LOCALIZED BLOWING AND DRIFTING SNOW. DRIER AIR
WILL ENTER THE PICTURE TONIGHT...WITH PLN POSSIBLY CLEARING AND
VFR CONDITIONS MAKING A RETURN TO APN WHILE TVC/MBL MAINTAIN
PERIODIC LAKE EFFECT SNOW SHOWERS.
LAWRENCE
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 PM EST FRIDAY FOR MIZ008-015>019-
022>024-027>029-033-034.
WINTER STORM WARNING UNTIL 7 PM EST FRIDAY FOR MIZ020-021-025-
026-031-032.
LH...SMALL CRAFT ADVISORY UNTIL 11 PM EST FRIDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 11 PM EST FRIDAY FOR LMZ323-341-342.
GALE WARNING UNTIL 5 PM EST FRIDAY FOR LMZ344>346.
LS...SMALL CRAFT ADVISORY UNTIL 11 PM EST FRIDAY FOR LSZ321-322.
&&
$$
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
626 PM CST SAT JAN 14 2012
.UPDATE...
00Z AVIATION DISCUSSION ADDED BELOW.
&&
.DISCUSSION...
LIGHT SNOW WILL CONTINUE EARLY THIS EVENING ACROSS FAR EASTERN MN
AND WESTERN WI AS A MID LEVEL CIRCULATION NEAR KSTC DRIVES
SOUTHEAST. ACCUMULATIONS WILL BE LIGHT AND LESS THAN A HALF INCH.
THERE IS SOME CONCERN THAT AS THE MID LEVEL CIRCULATION PASSES
SOUTHEAST THIS EVENING...ONLY LOW LEVEL SATURATION WILL EXIST WITH
CLOUD TEMPERATURES BETWEEN -5 AND -10 DEG C. THIS WILL ALLOW FOR
AN OPPORTUNITY FOR SOME LIGHT FREEZING DRIZZLE...MAINLY OVER WEST
CENTRAL WI. KEPT THE MENTION OUT FOR NOW BUT SOMETHING THE EVENING
SHIFT WILL NEED TO MONITOR.
IT WILL BE WARMER ON SUNDAY IN THE WAKE OF A WARM FRONT.
HOWEVER...THERE ARE SEVERAL CONCERNS ON JUST HOW WARM TO GO. THERE
ARE SOME INDICATIONS THAT MID/HIGH LEVEL CLOUDINESS COULD BE
RATHER EXTENSIVE ACROSS THE NORTHERN AND EASTERN AREAS OF THE FA
DURING THE LATE MORNING AND EARLY AFTERNOON HOURS. THIS IS ALSO AN
AREA WHERE SNOW COVER IS BETTER...ESPECIALLY OVER WEST CENTRAL WI.
THIS SHOULD LIMIT JUST HOW WARM THESE AREA AREA. USED THE MIX DOWN
TOOL IN COMBINATION WITH SOME BC DATA FOR HIGHS. THIS RESULTED IN
HIGHS RANGING FROM THE LOWER 40S FROM APPLETON TO FAIRMONT TO THE
UPPER 20S NEAR LADYSMITH...WHICH SEEMS VERY REASONABLE.
SUNDAY WILL BE THE WARMEST DAY IN THE NEXT SEVEN AS A PACIFIC
COLD FRONT MOVES THROUGH SUNDAY NIGHT/MONDAY MORNING FOLLOWED BY
AN ARCTIC FRONT ON WEDNESDAY. MID LEVEL FRONTOGENESIS DEVELOPS IN
THE WAKE OF THE FRONT MONDAY NIGHT WITH SNOW LIKELY FOR ABOUT THE
SOUTHERN HALF OF MN AND MUCH OF WEST CENTRAL WI. JUST ABOUT ALL
MODEL RUNS TODAY SHOWING SOUTHERN MN IN THE PATH FOR AN INCH OR
TWO OF SNOW MONDAY NIGHT/EARLY TUESDAY WITH EVEN THE ECMWF
DROPPING A LITTLE SOUTH TODAY. LIKELY POPS COVER THE AFOREMENTIONED
AREAS.
IT LOOKS RATHER ENERGETIC ALONG THE ARCTIC FRONT FROM WEDNESDAY
INTO FRIDAY WITH SEVERAL CHANCES FOR ACCUMULATING SNOW. TIMING
DIFFERENCE ARE DRAMATIC. THURSDAY NIGHT/FRIDAY SHOW SOME
CONTINUITY WITH CHANCE POPS IN PLAY FOR THESE PERIODS. A WARMING
TREND IS SEEN FOR NEXT WEEKEND AS A LOW PRESSURE SYSTEM MOVES EAST
ALONG THE INTERNATIONAL BORDER...LIFTING THE ARCTIC AIR BACK
NORTH.
&&
.AVIATION.../00Z TAF ISSUANCE/
LIGHT SN MAINLY CONFINED TO WRN WI NOW AS ELONGATED VORT MAX IS
SLOWLY SHIFTING EAST ACROSS THE AREA. SREF PROBS ALONG WITH HRRR
REFLECTIVITY FORECASTS INDICATE THAT THE REMAINING SNOW SHOULD
BASICALLY DRY UP IN PLACE QUICKLY THIS EVENING...WHICH IS
SUPPORTED BY CURRENT DECREASING TRENDS ON RADAR. BECAUSE OF
THIS...ONLY WENT WITH A TEMPO GROUP FOR MVFR -SN AT EAU THROUGH
3Z. NEXT ISSUE TO TACKLE IS WORKING MVFR PTCHY IFR CIGS EAST
ACROSS THE AREA TONIGHT. USED 925-850MB RH OFF THE NAM/GFS/RUC TO
SLOWLY PUSH THESE CLOUDS NE OUT AHEAD OF THE WARM FRONT.
HOWEVER...SREF MVFR CIG PROBS AND HRRR CLOUD HEIGHT FORECAST
SHOWING THE BACK EDGE OF THE CLOUDS ALONG AN MSP TO STC LINE AT
12Z...SO IMPROVEMENTS MAY NEED TO BE DELAYED FURTHER IF THESE
SLOWER SOLUTIONS ARE CORRECT. AFTER THAT...GRADIENT WILL BE TIGHT
BY SUNRISE SUNDAY...WITH GUSTY SE WINDS QUICKLY ENVELOPING THE TAF
SITES...BUT SPEEDS ACROSS MN WILL BEGIN TO DECREASE DURING THE
AFTERNOON AS GRADIENT SLACKENS AHEAD OF NEXT COLD FRONT. THAT
FRONT LOOKS TO MOVE INTO WRN MN SHORTLY AFTER 21Z.
KMSP...WATCHING ANOTHER BATCH OF REFLECTIVITY TO THE WEST CLOSELY
THIS EVENING. FORTUNATELY...VERY FEW WEATHER REPORTS HAVE BEEN
NOTED WITH IT...BUT 00Z KMPX SOUNDING SHOWING SATURATION UP TO
-10C...SO IF PRECIP IS OBSERVED OUT OF THIS BATCH OF
REFLECTIVITY...IT MAY LIKELY BE IN THE FORM OF FZDZ. TIMING THIS
BATCH THROUGH...THE 2 TO 4Z TIME FRAME IS WHAT WILL NEED TO BE
WATCHED. BASED ON SURROUNDING OBS...CIGS WILL BASICALLY REMAIN
BELOW 017 FOR AS LONG AS THE CLOUDS ARE OVHD...AS NOTED
ABOVE...THEY MAY BE OVHD LONGER THAN CURRENTLY INDICATED. IN
ADDITION...THOUGH THERE HAS NOT BEEN MANY PRECIP REPORTS WITH THE
REFLECTIVITY TO THE WEST...THERE HAVE BEEN A FEW IFR CIGS...AND
THAT 2 TO 4Z WINDOW WOULD ALSO BE THE TIME FOR SEEING CIGS BELOW
010. CURRENTLY...FROPA LOOKS TO OCCUR CLOSE TO 06Z MON...BUT WINDS
DO LOOK TO DIE DOWN BY THE AFTERNOON AHEAD OF IT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
RAH/MPG
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
342 PM CST FRI JAN 13 2012
.SHORT TERM...TONIGHT THROUGH MONDAY.
THE PRIMARY CONCERNS IN THE SHORT TERM WILL THE HOW FAR SOUTHWEST
TO CARRY THE LIGHT SNOW AND FLURRIES OVERNIGHT AND EARLY
SATURDAY...TEMPERATURES SATURDAY AND SUNDAY...HOW FAR NORTH WILL
THE LIGHT RAIN AND DRIZZLE MAKE IT MONDAY MORNING...AND LIGHT SNOW
MOVING IN FROM THE WEST MONDAY.
AT 18Z...LIGHT SNOW RETURNS HAVE SPREAD INTO PARTS OF MT AND BY
20Z GGW WAS DOWN TO 1/2SM IN SNOW. SINCE THE OPERATIONAL MODELS
WERE ALL DRY AT THAT TIME IN MT...NOT REAL CONFIDENT IN HOW THEY
ARE HANDLING THIS SYSTEM. THE SHORTWAVE TROF OVER THE WRN DAKOTAS
IS FORECAST TO QUICKLY DROP SOUTHEAST OVERNIGHT INTO MISSOURI BY
12Z. THIS WITH WAA...UPWARD VERTICAL MOTION WITH THE WAVE...AND
POTENTIAL VORTICITY ADVECTION. THE 12Z/18Z CONTINUED DRY EXCEPT
FOR HARRISON CO IN IOWA. THE GFS HAS SOME LIGHT PRECIPITATION
MAKING IT INTO NORTHEAST NEB WHILE THE 00Z/12 EC/12Z 4KM WRF AND
THE LATEST HRRR ARE A BIT STRONGER WITH THE WAVE IN GENERATING
LIGHT SNOW FROM NORTHEAST NEBRASKA INTO WESTERN IOWA. ALTHOUGH
THERE ARE QUITE A FEW RETURNS SHOWING UP AT 21Z...SFC REPORTS ARE
STILL SPARSE IN REPORTING THE SNOW. LOOKING AT THE FORCING...
SATURATION...AND COLDEST TEMPS HAVE INCLUDED SOME SLIGHT CHC TO
CHC POPS OVER ESPECIALLY THE NORTHEASTERN THIRD OF THE CWA. AT
THIS TIME ONLY ADDED SOME VERY LIGHT AMOUNTS TO THE NORTHEAST.
ALTHOUGH SURFACE DEWPOINTS ARE VERY LOW (BELOW ZERO WRN IA AND THE
ALONG THE MISSOURI RIVER)...LOOK FOR THEM TO INCREASE OVERNIGHT
INTO THE TEENS AND 20S. WITH A SURFACE LOW TRACKING ACROSS THE
AREA OVERNIGHT...TEMPERATURES WILL BE TRICKY...FALLING OFF QUICKLY
TONIGHT IN WRN IOWA...BUT BEING HELD UP ACRS THE WRN CWA.
MID LEVEL RIDGING WILL BUILD IN FOR THE WEEKEND. WARMER
TEMPERATURES ARE FORECAST FOR WEEKEND WITH 50S FOR SUNDAY. THE
NEXT COLD FRONT MOVES THROUGH OVERNIGHT SUNDAY AND LOW CLOUDS AND
SOME DRIZZLE COULD DEVELOP IN SOUTHWEST IOWA. COLDER AIR WILL
RETURN FOR MONDAY WITH LIGHT SNOW DEVELOPING OVER SOUTH DAKOTA AND
WESTERN AND CENTRAL NEBRASKA. THIS LIGHT SNOW COULD START TO MAKE
IT INTO PARTS OF THE WESTERN FORECAST AREA BY DAY/S END.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY.
MODELS CERTAINLY DIVERGE REGARDING THE AMOUNT AND INTENSITY OF COLD
AIR PLUNGING INTO THE PLAINS BY MID TO LATE WEEK. THE OPERATIONAL
GFS HAS REMAINED THE COLDEST OF THE MEDIUM RANGE MODELS...WITH ECMWF
THE WARMEST. GFS ENSEMBLE MEMBERS OFFER NO HELP AS THE SPREAD IS
WIDE HERE TOO. IN FACT...THE 00Z ENSEMBLE TEMPERATURES FOR THURSDAY
HIGHS RANGED FROM 21 TO 49 AT OMAHA.
LEADING UP TO THIS TIME PERIOD...A SIMILAR EVOLUTION OF THE UPPER
FLOW PATTERN IS NOTED BY GFS/ECMWF. BOTH SHOW A BROAD TROUGH OVER
THE CENTER OF THE COUNTRY WITH A SHORTWAVE MOVING THROUGH NEBRASKA
AND IOWA MONDAY NIGHT AND TUESDAY. AND BOTH MODELS BREAK OUT LIGHT
SNOW WITH THIS SYSTEM...ESPECIALLY ACROSS NORTHERN NEBRASKA INTO
NORTHERN IOWA. OUR CURRENT FORECAST HAS LIGHT SNOW IN THE FORECAST
MONDAY NIGHT...SO LEFT THAT UNCHANGED. HOWEVER...SLIGHTLY SLOWER
ECMWF KEEPS SNOW IN FOR TUESDAY. IF THIS OCCURS IT SHOULD ONLY
AFFECT OUR EAST AND SHOULD BE ENDING QUICKLY IN THE MORNING.
THEN UPPER PATTERN BEGINS TO FLATTEN OUT SOME...WITH NORTHWEST FLOW
THE CONSENSUS FOR WEDNESDAY. HIGHS IN THE 20S TUESDAY IN COOL
ADVECTION REGIME WILL WARM INTO THE 30S WEDNESDAY.
THURSDAY IS THE BIG QUESTION MARK AS THE GFS CONTINUES TO SHOW
STRONG BAROCLINIC ZONE DROPPING THROUGH THE CWA WHILE ECMWF KEEPS
BRUNT OF COLD AIR TO OUR NORTHEAST. DURING NORMAL WINTERS WOULD
EXPECT THE GFS AND COLD AIR TO WIN OUT...BUT THIS HAS BEEN ANYTHING
BUT A NORMAL WINTER. WE HAVE SEEN THESE SCENARIOS ADVERTISED AT DAYS
6 AND 7 BEFORE...AND TRENDING TOWARD WARMER SOLUTIONS HAS BEEN BEST.
ESPECIALLY WITH LIMITED SNOW COVER TO OUR NORTH. BOTH SIDES OF THE
ARGUMENT HAVE MERIT...SO TO STAY CONSISTENT WITH CURRENT
FORECAST...SURROUNDING OFFICES AND WIDELY DIVERGENT MODELS...WILL
HAVE TO KEEP TEMPERATURES CLOSE TO WHAT WE CURRENTLY HAVE GOING WITH
HIGHS IN THE 20S AND LOWER 30S. WHATEVER THE CASE...EXPECT A LITTLE
WARMER CONDITIONS ON FRIDAY AS RETURN FLOW SETS UP. MAY ALSO SEE
SOME LIGHT SNOW WITH THIS SCENARIO.
&&
.AVIATION...
18Z TAFS FOR KOMA...KLNK...AND KOFK.
VFR CONDITIONS ARE EXPECTED TO PREVAIL AT ALL SITES THROUGH THE
TAF PERIOD. A FRONTAL BOUNDARY WILL APPROACH THE CWA THIS
AFTERNOON...BRINGING WINDS AROUND TO THE SOUTHEAST AHEAD OF THE
FRONT. OVERNIGHT...WINDS BEHIND THE FRONT ARE EXPECTED TO
INCREASE AND SWITCH TO THE NORTHWEST.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
ZAPOTOCNY/DERGAN/ROURKE
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
945 PM EST SAT JAN 14 2012
.SYNOPSIS...
A FEW CLOUDS WILL ACCOMPANY A WEAK SYSTEM OVERNIGHT. HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTH OVER THE NEXT
SEVERAL DAYS. RAIN CHANCES RETURN WITH A COLD FRONT LATE TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 935 PM SATURDAY...LATEST RUC AND NAM MODEL INDICATE A THINNING
SWATH OF MOISTURE BETWEEN 850 MB AND 500 MB ASSOCIATED WITH THE
CHANNELED 5H VORT PASSAGE LATER TONIGHT. MID LEVEL CLOUD DECK TO
AFFECT THE ILM CWA OVERNIGHT WITH POSSIBLY 5K-6K LOW LEVEL CLOUD
DECK ACROSS THE NORTHERNMOST PORTIONS OF THE ILM CWA. JUST TOO DRY
BELOW 8H FOR PCPN TO REACH THE GROUND B4 EVAPORATING OR IN THIS CASE
SUBLIMATE. WILL CONTINUE TO REFRAIN FROM PLACING SNOW FLURRIES IN
THE FORECAST BUT WOULD NOT BE SURPRISED TO HEAR ABOUT OR THE
OBSERVATION OF FLAKES JUST NORTH OF THE ILM CWA PRIOR TO DAYBREAK
SUNDAY. THERE WILL BE A SFC REFLECTION...WITH THE SFC LOW MOVING
FROM THE TN-NC BORDER TO OFF CAPE LOOKOUT BY DAYBREAK SUNDAY. WINDS
TO SLOWLY PICK UP OVERNIGHT...WITH S-SW AHEAD OF THE LOW...VEERING
TO W TO NW AFTER ITS PASSAGE. MIN TEMPS HAVING DROPPED AND
STABILIZED THIS EVENING...WILL ACTUALLY INCREASE AHEAD OF THE LOW
OVERNIGHT. A REINFORCING SHOT OF COLD AIR WILL OCCUR AFTER THE LOWS
PASSAGE BY DAYBREAK SUN VIA LATEST MODEL PARTIAL THICKNESSES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...A LARGELY MOISTURE-STARVED CLIPPER WILL BE
CROSSING THE REGION AT THE START OF THE PERIOD. A FEW RADAR ECHOES
MAY BE OBSERVED BUT ANY PRECIP WILL BE VERY HARD PRESSED TO REACH
THE GROUND. OTHERWISE VERY QUIET WEATHER THROUGH THE PERIOD. IN FACT
FORECAST SOUNDINGS SHOW THAT ONLY CLOUDS IN THE SHORT TERM WILL BE A
GRADUAL INCREASE OF CIRRUS AND EVENTUALLY CIRROSTRATUS LATE MONDAY
AND MONDAY NIGHT. AN EXITING SHORTWAVE AND SURFACE HIGH PRESSURE
BUILDING IN FROM THE NORTH WILL BRING COME CAA ON SUNDAY KEEPING
TEMPS JUST A FEW DEGREES BELOW CLIMO...GENERALLY IN THE LOW 50S.
850MB TEMPS REMAIN IN THE -2 TO -4C RANGE BUT LIGHT WINDS SHOW THAT
MIXING WILL PROBABLY ONLY DEEPEN TO ABOUT 900MB. THE SURFACE RIDGE
WILL MAKE ITS WAS OFF THE NC/VA COASTLINE LATE MONDAY ALLOWING FOR A
TURN TO THE SOUTH IN THE SURFACE AND LOWER LEVELS. OVERALL WINDS
REMAIN QUITE LIGHT HOWEVER SO SHALLOW MIXING WILL TEMPER ANY WARMUP
DESPITE THE GOOD WARMING SEEN AT 850MB. MID LEVEL FLOW REMAINS LOW
IN AMPLITUDE...NEARLY ZONAL. TWIN UPPER LEVEL JET MAXES DEVELOPING
OVER THE MIDDLE OF THE NATION WILL LEAD TO THE AFOREMENTIONED
INCREASE OF CIRRUS LEVEL MOISTURE LOCALLY ON MONDAY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 230 PM SATURDAY...MODELS BRING FRONT AND ASSOCIATED PCPN OFF
THE COAST DURING THE EARLY PART OF THE LONG TERM FORECAST WITH HIGH
PRESSURE BUILDING INTO THE EASTERN PORTION OF THE COUNTRY WITH
COOLER TEMPS FOR THURSDAY WITH A NNE FLOW ACROSS THE REGION. HIGH
SLIDES OFF THE COAST FRIDAY WITH NICE RETURN FLOW SETTING UP BEHIND
IT WITH TEMPS MODERATING INTO THE LOWER 60S FRIDAY AND MID 60S ON
SATURDAY A GOOD 5-10 DEGREES ABOVE NORMAL. H5 PATTERN REMAINS FLAT
AND PROGRESSIVE WITH NEXT UP STREAM SHORT WAVE MOVING OUT OF THE
CENTRAL/SOUTHERN PLAINS INTO THE LOWER OHIO/TENNESSEE VALLY ON
SATURDAY. THE ECMWF IS DEEPER AND MORE AGGRESSIVE WITH THIS FEATURE
DEVELOPING A SURFACE LOW IN THE OHIO VALLEY WHILE THE GFE HAS A MORE
OPEN WAVE DEVELOPING. BOTH MODELS SHOW MOISTURE STREAMING UP FROM
THE GULF AHEAD OF THIS FEATURE WITH THE ECMWF BRINGING SOME PCPN
INTO THE CWA DURING THE DAY SATURDAY. H8 MOISTURE TRANSPORT VECTORS
INDICATE BOTH GULF AND ATLANTIC MOISTURE BEING TAP MAXIMIZED BETWEEN
18Z SAT AND 06Z SUNDAY. THE GFE/CMC NHEM 12Z MODEL RUNS ARE NOT AS
AGGRESSIVE HERE AS THE ECMWF AND IS MORE LIMITED WITH THE MOISTURE.
WITH PLENTY OF TIME YET TO ANALYZE THIS NEXT FEATURE WILL LEAN
TOWARDS THE GFE/CMC SOLUTION NOW WITH NEXT SYSTEM MOVING ACROSS THE
AREA ON SATURDAY WITH SOME PCPN.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 00Z...HIGH CONFIDENCE FOR VFR CONDITIONS THROUGH THE FORECAST
PERIOD. A WEAK SHORT WAVE AND ASSOCIATED LOW PRESSURE WILL CROSS THE
REGION THROUGH THE OVERNIGHT HOURS. ANY PRECIPITATION SHOULD STAY
NORTH OF THE TERMINALS...WITH ONLY A MID CLOUD CEILING EXPECTED.
AFTER THE VORT MOVES THROUGH...EXPECT A WIND SHIFT TO THE NORTHWEST
BY MID MORNING...GUSTY...WITH SCATTERED SKIES.
EXTENDED OUTLOOK...LOW CONFIDENCE IFR FOG INLAND TERMINALS EARLY
TUESDAY MORNING AND SHOWERS/TEMPO IFR LATE TUESDAY INTO WEDNESDAY.
OTHERWISE VFR.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 930 PM SATURDAY...A QUICK MOVING CLIPPER LOW AND ASSOCIATED
COLD FRONT...IS PROGGED TO MOVE ACROSS AND EXIT THE ILM WATERS BY
DAYBREAK SUNDAY. POST FRONTAL W TO NW WINDS WILL INCREASE TO 15 TO
25 KT BY DAYBREAK SUNDAY AND CONTINUE INTO MIDDAY SUNDAY. LATEST
HRRR MODEL SFC WINDS INDICATE WNW 15-25 KT WINDS MATERIALIZING
DURING THE PRE-DAWN HRS OF SUNDAY. THE TIGHTENED SFC PG AND CAA
AFTER THE PASSAGE OF THE CLIPPER LOW...SHOULD CONTINUE THESE
WINDS FOR A PERIOD LONG ENOUGH TO WARRANT THE RAISING OF A BRIEF
SCA. SIGNIFICANT SEAS WILL BE RULED BY THE LOCALLY PRODUCED WIND
DRIVEN...3 TO 6 SECOND PERIOD WAVES. AND WITH AN OFFSHORE
TRAJECTORY...A RANGE OF SEAS WILL BE FORECAST. FRYING PAN SHOALS
WILL EXHIBIT WASHING MACHINE TYPE CONDITIONS...WITH LOCALLY HIGHER
WAVES LIKELY.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...NW WINDS WILL INCREASE SOME EARLY SUNDAY WITH
THE OFFSHORE EXIT OF A CLIPPER TYPE OF DISTURBANCE AT BOTH THE
SURFACE AND ALOFT. CAUTIONARY HEADLINES ARE NOT ANTICIPATED EVEN
WITH A LITTLE MIXING AS FORECAST SOUNDINGS SHOW NO HIGHER THAN 20
KNOTS THROUGH MOST OF WHAT SHOULD BE THE BOUNDARY LAYER OVER THE
MARINE ZONES...ESPECIALLY GIVEN THE COOLER SSTS OF THE NEARSHORE
WATERS. SUNDAY AFTERNOON WILL BRING A VEERING AND DECREASING WIND
REGIME AS HIGH PRESSURE BUILDS ACROSS VA AND THE GRADIENT EASES
LOCALLY. THIS SAME HIGH WILL ONLY SLOWLY MIGRATE EASTWARD FOR THE
REMAINDER OF THE SHORT TERM PERIOD ALL WHILE KEEPING A WEAK RIDGE
AXIS INTO THE COASTAL CAROLINAS. AS SUCH THE WINDS WILL REMAIN QUITE
LIGHT...GENERALLY 10KT...LEADING TO A MERE 2 FT WIND WAVE. AN
ADDITIONAL VEER TO A SOUTHERLY DIRECTION IS SLATED FOR MONDAY NIGHT
AS THE HIGH MOVES EVEN FURTHER OUT TO SEA AND A COLD FRONT REACHES
THE OH AND MS RIVER VALLEY REGIONS. AN INCREASE IN SPEED WILL ALSO
RESULT MONDAY NIGHT...GRADUALLY AT FIRST AND THEN WITH MORE VIGOR
AFTER ABOUT 06Z. SEAS COULD BUILD TO 5 FT ALONG THE EASTERN FRINGE
OF SOME OF THE ZONES NECESSITATING SCEC BUT A PEEK INTO THE LONG
TERM WOULD SUGGEST THAT A SMALL CRAFT ADVISORY WILL INSTEAD BE
HOISTED DUE TO FURTHER ANTICIPATED DETERIORATION OF CONDITIONS.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 230 PM SATURDAY...COLD FRONT APPROACHES THE WATERS ON TUESDAY
NIGHT INTO EARLY WEDNESDAY AND OFF THE COAST BY 12Z. TIGHT GRADIENT
WITH WINDS INCREASING FROM THE SW AT 20-25 KTS AHEAD OF FRONT WITH
SEAS BUILDING TO 5-7 FEET RESULTING IN SCA CRITERIA LATE TUESDAY
INTO MID DAY WEDNESDAY. ONCE FRONTS PASSES THE WINDS BACK FROM THE
SW TO WEST AND THEN BECOME MORE NORTHERLY BY 18Z WITH THE SEAS
DIMINISHING TO 3-5 FEET...2-4 FEET NEAR SHORE. WINDS WILL REMAIN
BRISK AT 15-20 KTS AND VEER TO THE NE ON THURSDAY BEFORE SLOWLY
DIMINISHING AS HIGH PRESSURE BUILDS ACROSS THE WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 3 AM TO 1 PM EST SUNDAY FOR
AMZ250-252-254-256.
&&
$$
SYNOPSIS...MBB
NEAR TERM...DCH
SHORT TERM...MBB
LONG TERM...MAC
AVIATION...HDL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
909 PM EST SAT JAN 14 2012
.SYNOPSIS...
A STRONG UPPER LEVEL DISTURBANCE...AND ACCOMPANYING CLIPPER SURFACE
LOW...WHICH TRACK SOUTHEAST ACROSS OUR REGION OVERNIGHT. HIGH
PRESSURE WILL FOLLOW FOR SUNDAY INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 909 PM SATURDAY...
PROBLEM OF THE NIGHT WILL BE THE TRACK OF THE MID-UPPER VORTICITY
MAXIMUM FROM SW VA ACROSS NORTHERN/NE NORTH CAROLINA... AND THE
CHANCE OF LIGHT SNOW/FLURRIES ALONG AND NORTH OF THE TRACK.
THE LATEST WV SATELLITE DATA INDICATED THAT THE MID-UPPER LEVEL
VORTICITY MAXIMUM WAS TRACKING ESE ALONG THE WVA/VA BORDER INTO SW
VA. THE RADAR REFLECTIVITY HAS BEEN INCREASING IN COVERAGE AND IN
INTENSITY IN THE PAST FEW HOURS... MAINLY NORTH OF A LINE FROM BOONE
TO KING TO WENTWORTH. LIGHT SNOW HAS BEEN REPORTED ALONG THE BLUE
RIDGE WITH SOME LIGHT ACCUMULATIONS BEGINNING. VISIBILITIES FROM
WYTHEVILLE TO HILLSVILLE/GALAX ARE BETWEEN 3/4 AND 1 MILE WITH SNOW.
THE SUBCLOUD LAYER APPEARS TO HAVE MOISTENED UP QUICKLY AT
ELEVATIONS OF 3K FEET AND ABOVE... ALONG AND NORTH OF THE TRACK OF
THE VORT MAX. HOWEVER... OFF THE BLUE RIDGE... THE SUBCLOUD LAYER
HAS BEEN SLOWER TO MOISTEN UP. NO SNOW HAS BEEN OBSERVED IN THE
TRIAD AS OF 900 PM. IN FACT... THE REFLECTIVITY RETURNS HAVE BEEN
ONLY 5-10DBZ OVER THE WINSTON-SALEM AREA... AND THE SUBCLOUD LAYER
WAS STILL TOO DRY (20 DEGREE F) TEMPERATURE/DEW POINT TEMPERATURE
DEPRESSION AT WINSTON-SALEM AND GREENSBORO.
EXTRAPOLATION OF THE VORTICITY MAXIMUM ESE PER THE LATEST OBSERVED
DATA AND RUC SUGGESTS THAT THE FAVORED AREAS FOR SOME FLURRIES WILL
BE THE NORTHERN PIEDMONT AND NORTHERN COASTAL PLAIN. THE P-TYPE
WOULD BE SNOW SUPPORTED BY THE CURRENT BELOW FREEZING TEMPERATURE
PROFILE AT GSO... WITH THE EXCEPTION OF THE BOUNDARY LAYER... WHERE
CURRENT READINGS WERE IN THE MID 30S... AND DEW POINTS IN THE UPPER
TEENS AND LOWER 20S. PARTIALS INDICATE SNOW AS WELL ACROSS THE
NORTHERN ZONES. THE 00Z/15 JANUARY PARTIALS CAME IN AT 1503M/1299M
ON THE GSO RAOB. CHECKING PAST EVENT CASES... THERE WERE NO
MEASURABLE SNOW EVENTS AT GSO WITH THESE OBSERVED PARTIALS. THIS IS
SIMPLY BECAUSE THE OBSERVED MID LEVELS ARE VERY COLD... AND DRY...
WHICH IS COMMON WITH THESE NW FLOW SYSTEMS... WHEN THE VORT TRACKS
OVERHEAD.
WE WILL KEEP A CHANCE SNOW FLURRIES ACROSS THE NORTH (MAINLY NORTH
OF I-40 TO RALEIGH... THEN NORTH OF US-64 FROM RALEIGH TO WILSON).
THIS WILL BE ALONG AND NORTH OF THE EXPECTED TRACK OF THE VORT MAX.
STILL... THERE IS NOT EXPECTED TO BE ANY ACCUMULATION AS THE SNOW
WOULD BE TOO LIGHT.
SKIES WILL CLEAR LATER TONIGHT... IT WILL BE COLD AGAIN WITH LOWS IN
THE 20S.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 305 PM SATURDAY...
SUNDAY AND SUNDAY NIGHT: A TRAILING DISTURBANCE EMBEDDED WITHIN THE
ELONGATED VORTICITY AXIS BEARING THE LEAD CLIPPER WAVE...WILL PIVOT
THROUGH THE DEPARTING BASE OF THE L/W TROUGH EARLY SUN...FOLLOWED BY
SIGNIFICANT (150M/12HR) MID LEVEL HEIGHT RISES AND THE ARRIVAL OF
STRONG (1035 MB) SURFACE HIGH PRESSURE THROUGH THE REMAINDER OF THE
WEEKEND. THIS SHOULD YIELD SKIES BECOMING SUNNY SUNDAY...WITH CLEAR
SKIES LIKELY TO CONTINUE UNTIL CIRRUS ASSOCIATED WITH A SW US UPPER
JET SPREAD INTO OUR REGION LATE SUN NIGHT. THE HIGH CLOUDS ARE
EXPECTED TO REMAIN THIN ENOUGH AND BE DELAYED SUCH THAT RADIATIONAL
COOLING CONDITIONS WILL BE EXCELLENT AND LEAD TO LOWS IN THE 21 TO
26 DEGREE RANGE. HIGHS GENERALLY 43 TO 50 DEGREES.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 255 PM...
RIDGING SURFACE AND ALOFT MONDAY MORNING. INCREASING MOISTURE IN
WEST SOUTHWEST FLOW AHEAD OF AN APPROACHING SHORT WAVE BUT WEATHER
LIMITED TO CLOUDS THROUGH MONDAY NIGHT. 850 MILLIBAR FLOW INCREASES
TO FIFTY KNOTS OR MORE BY SUNRISE TUESDAY BUT IS RELATIVELY UNIFORM
AND PERHAPS SPEED DIVERGENT. LOW LEVELS ARE STABLE AND THE PARENT
LOW TO THE TROUGH WELL NORTH IN THE EASTERN GREAT LAKES BY SUNSET
TUESDAY. THUS THIS COULD BE A SITUATION OF A VERY HIGH CHANCE FOR
VERY LITTLE RAIN TUESDAY. FORTY PERCENT CHANCE BY TUESDAY AFTERNOON
BUT THIS MAY NEED TO BE DOUBLED... BUT AGAIN FOR VERY LOW AMOUNTS.
THE SURFACE TROUGH FORECAST TO BE OFFSHORE BY SUNRISE WEDNESDAY...
AND RAIN CHANCES WILL DRY UP FROM WEST TO EAST TUESDAY NIGHT... WITH
THE REMAINDER OF THE FORECAST PERIOD DRY.
BEHIND THE FRONT SURFACE HIGH PRESSURE SETTLE OVER NORTH CAROLINA
THURSDAY MORNING... AND IS CENTERED OFFSHORE BY EVENING... NOSING
BACK INTO THE SOUTHEAST STATES. THERE IS ENOUGH AGREEMENT IN AN
UPPER LEVEL WAVE REACHING THE MOUNTAINS SATURDAY TO INTRODUCE A
CHANCE FOR RAIN.
TUESDAY IS EXPECTED TO BE BREEZY WITH SOME GUSTS TO 30 MPH.
AFTERNOON TEMPERATURES NEAR NORMAL MONDAY AT 50 TO 55... WITH RISING
TO NEAR 60 NORTHWEST TO NEAR 67 SOUTHEAST TUESDAY. HIGH TEMPERATURES
MOSTLY 45 TO 50 BEHIND THE FRONT WEDNESDAY AND THURSDAY... RISING
INTO THE FIFTIES FRIDAY... AND LOW TO MID 60S SATURDAY.
LOW TEMPERATURES AROUND 40 MONDAY NIGHT... 35 TO 45 TUESDAY NIGHT.
LOW TEMPERATURES IN THE MID 20S WEDNESDAY NIGHT... RISING INTO THE
40S FRIDAY NIGHT.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 645 PM SATURDAY...
VFR CONDITIONS ARE EXPECTED TO PERSIST THROUGH THE CURRENT TAF
PERIOD. HOWEVER...CLOUD COVER WILL INCREASE FROM NORTHWEST TO
SOUTHEAST OVER THE NEXT SEVERAL HOURS AS A DISTURBANCE IN THE
NORTHWESTERLY FLOW APPROACHES THE REGION...BUT CEILINGS ARE EXPECTED
TO REMAIN AOB 5KFT. THERE IS ALSO A CHANCE OF A FEW FLURRIES
OCCURRING ACROSS CENTRAL NC TONIGHT ASSOCIATED WITH THE
AFOREMENTIONED DISTURBANCE...MOSTLY LIKELY ACROSS THE NORTHERN HALF
OF THE FORECAST AREA. BEHIND THE DISTURBANCE...WINDS WILL SHIFT TO A
NORTHERLY DIRECTION AND SKIES WILL CLEAR OUT BY SUNDAY MORNING.
LOOKING AHEAD: A FRONTAL SYSTEM WILL BRING A CHANCE OF IFR CEILINGS
TUE MORNING AND CHANCE OF RAIN SHOWERS AND ASSOCIATED SUB-VFR
CONDITIONS TUESDAY AFTERNOON AND NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BADGETT
NEAR TERM...BADGETT/MWS
SHORT TERM...MWS
LONG TERM...RLH
AVIATION...KRR/MWS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
605 PM EST SAT JAN 14 2012
.SYNOPSIS...
A FEW CLOUDS WILL ACCOMPANY A WEAK SYSTEM OVERNIGHT. HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTH OVER THE NEXT
SEVERAL DAYS. RAIN CHANCES RETURN WITH A COLD FRONT LATE TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 600 PM SATURDAY...LATEST RUC MODEL INDICATES A THICKER SWATH
OF MOISTURE BETWEEN 850 MB AND 500 MB ASSOCIATED WITH THE CHANNELED
VORT LATER TONIGHT. FOR NOW...BEEFED UP THE CLOUDS FOR THE NORTHERN
PORTIONS OF THE ILM CWA...NOTHING MORE AS OF YET.
PREVIOUS DISCUSSION............................................
AS OF 230 PM SATURDAY...TEMPERATURES WILL DROP OFF QUICKLY THIS
EVENING BENEATH MAINLY CLEAR SKIES...ALTHOUGH SHREDS OF CIRRUS
MAY GLIDE SWIFTLY OVER OUR NORTHERN ZONES BY THE LATE AFTERNOON
AHEAD OF A CLIPPER LOW CUTTING ACROSS TENNESSEE PRESENTLY.
STRONG...CHANNELED VORTICITY WILL RAPIDLY TEAR ACROSS THE BASE OF
A PASSING UPPER TROUGH BETWEEN 9Z-12Z OVER THE EASTERN CAROLINAS
EARLY SUNDAY MORNING. A SURFACE REFLECTION EXISTS IN THE FORM OF
A DRY COLD FRONT WHIPPING ACROSS OUR AREA IN THE PRE-DAWN HOURS.
AHEAD OF THIS CLIPPER-LIKE SYSTEM...NAM BUFR SOUNDINGS INDICATE
7-10 KFT CLOUDS FROM MIDNIGHT THROUGH DAYBREAK MOVING RAPIDLY WEST
TO EAST OVER PRIMARILY OUR NC ZONES. THE COLUMN BENEATH THESE
CLOUDS WILL REMAIN EXCEEDINGLY DRY. HOWEVER IT WOULD NOT BE
SHOCKING THAT OVERNIGHT RADAR ANIMATIONS CATCH VIRGA ECHOS FROM
SNOWFLAKES ALOFT...FAVORED MORESO TO THE NORTH. NO MENTION OF SNOW
IN OUR FORECAST SINCE WE EXPECT SUBLIMATION TO WIN OUT...AND NOT
SURVIVING THE DRY FALL TO SURFACE LEVEL. BUT ISOLATED FLAKES OVER
ROBESON...BLADEN...OR PENDER COUNTY IN THE PRE-DAWN HOURS CANNOT
BE ENTIRELY RULED OUT.
TEMPERATURE CURVES OVERNIGHT WILL BE NON-TYPICAL AND IT COULD BE
MANY LOCATIONS WILL SEE MINIMUM TEMPS REALIZED IN THE LATE EVENING
BEFORE WSW-SW WINDS INCREASE AND PARTIAL CLOUD COVER ARRIVES AFTER
MIDNIGHT. THUS WE SHOULD SEE A BUMP UPWARD IN TEMPS HEADING INTO
THE PRE-DAWN HOURS. YET EVEN THEN...LOOK FOR LOWS IN THE UPPER 20S
TO AROUND 30 BEFORE THIS OCCURS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...A LARGELY MOISTURE-STARVED CLIPPER WILL BE
CROSSING THE REGION AT THE START OF THE PERIOD. A FEW RADAR ECHOES
MAY BE OBSERVED BUT ANY PRECIP WILL BE VERY HARD PRESSED TO REACH
THE GROUND. OTHERWISE VERY QUIET WEATHER THROUGH THE PERIOD. IN FACT
FORECAST SOUNDINGS SHOW THAT ONLY CLOUDS IN THE SHORT TERM WILL BE A
GRADUAL INCREASE OF CIRRUS AND EVENTUALLY CIRROSTRATUS LATE MONDAY
AND MONDAY NIGHT. AN EXITING SHORTWAVE AND SURFACE HIGH PRESSURE
BUILDING IN FROM THE NORTH WILL BRING COME CAA ON SUNDAY KEEPING
TEMPS JUST A FEW DEGREES BELOW CLIMO...GENERALLY IN THE LOW 50S.
850MB TEMPS REMAIN IN THE -2 TO -4C RANGE BUT LIGHT WINDS SHOW THAT
MIXING WILL PROBABLY ONLY DEEPEN TO ABOUT 900MB. THE SURFACE RIDGE
WILL MAKE ITS WAS OFF THE NC/VA COASTLINE LATE MONDAY ALLOWING FOR A
TURN TO THE SOUTH IN THE SURFACE AND LOWER LEVELS. OVERALL WINDS
REMAIN QUITE LIGHT HOWEVER SO SHALLOW MIXING WILL TEMPER ANY WARMUP
DESPITE THE GOOD WARMING SEEN AT 850MB. MID LEVEL FLOW REMAINS LOW
IN AMPLITUDE...NEARLY ZONAL. TWIN UPPER LEVEL JET MAXES DEVELOPING
OVER THE MIDDLE OF THE NATION WILL LEAD TO THE AFOREMENTIONED
INCREASE OF CIRRUS LEVEL MOISTURE LOCALLY ON MONDAY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 230 PM SATURDAY...MODELS BRING FRONT AND ASSOCIATED PCPN OFF
THE COAST DURING THE EARLY PART OF THE LONG TERM FORECAST WITH HIGH
PRESSURE BUILDING INTO THE EASTERN PORTION OF THE COUNTRY WITH
COOLER TEMPS FOR THURSDAY WITH A NNE FLOW ACROSS THE REGION. HIGH
SLIDES OFF THE COAST FRIDAY WITH NICE RETURN FLOW SETTING UP BEHIND
IT WITH TEMPS MODERATING INTO THE LOWER 60S FRIDAY AND MID 60S ON
SATURDAY A GOOD 5-10 DEGREES ABOVE NORMAL. H5 PATTERN REMAINS FLAT
AND PROGRESSIVE WITH NEXT UP STREAM SHORT WAVE MOVING OUT OF THE
CENTRAL/SOUTHERN PLAINS INTO THE LOWER OHIO/TENNESSEE VALLY ON
SATURDAY. THE ECMWF IS DEEPER AND MORE AGGRESSIVE WITH THIS FEATURE
DEVELOPING A SURFACE LOW IN THE OHIO VALLEY WHILE THE GFE HAS A MORE
OPEN WAVE DEVELOPING. BOTH MODELS SHOW MOISTURE STREAMING UP FROM
THE GULF AHEAD OF THIS FEATURE WITH THE ECMWF BRINGING SOME PCPN
INTO THE CWA DURING THE DAY SATURDAY. H8 MOISTURE TRANSPORT VECTORS
INDICATE BOTH GULF AND ATLANTIC MOISTURE BEING TAP MAXIMIZED BETWEEN
18Z SAT AND 06Z SUNDAY. THE GFE/CMC NHEM 12Z MODEL RUNS ARE NOT AS
AGGRESSIVE HERE AS THE ECMWF AND IS MORE LIMITED WITH THE MOISTURE.
WITH PLENTY OF TIME YET TO ANALYZE THIS NEXT FEATURE WILL LEAN
TOWARDS THE GFE/CMC SOLUTION NOW WITH NEXT SYSTEM MOVING ACROSS THE
AREA ON SATURDAY WITH SOME PCPN.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 00Z...HIGH CONFIDENCE FOR VFR CONDITIONS THROUGH THE FORECAST
PERIOD. A WEAK SHORT WAVE AND ASSOCIATED LOW PRESSURE WILL CROSS THE
REGION THROUGH THE OVERNIGHT HOURS. ANY PRECIPITATION SHOULD STAY
NORTH OF THE TERMINALS...WITH ONLY A MID CLOUD CEILING EXPECTED.
AFTER THE VORT MOVES THROUGH...EXPECT A WIND SHIFT TO THE NORTHWEST
BY MID MORNING...GUSTY...WITH SCATTERED SKIES.
EXTENDED OUTLOOK...LOW CONFIDENCE IFR FOG INLAND TERMINALS EARLY
TUESDAY MORNING AND SHOWERS/TEMPO IFR LATE TUESDAY INTO WEDNESDAY.
OTHERWISE VFR.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 600 PM SATURDAY...BRIEF SCEC TO CONTINUE TO BE ADVERTIZED LATE
TONIGHT INTO THE SUNDAY AM HOUR. THIS ASSOCIATED WITH THE QUICK
MOVING CLIPPER LOW AND ASSOCIATED COLD FRONT...THAT IS PROGGED TO
MOVE ACROSS AND EXIT THE ILM WATERS BEFORE DAYBREAK SUNDAY. POST
FRONTAL W TO NW WINDS COULD BREACH SCA CRITERIA EITHER SUSTAINED OR
WITH FREQUENT WIND GUSTS. LATEST HRRR MODEL INDICATES WNW 20-30 KT
WINDS DURING THE PRE-DAWN HRS OF SUNDAY. WILL SEE WHAT THE VARIOUS
00Z MODEL RUNS TRICKLE IN WITH ON WHETHER DECIDING TO UPGRADE TO A
BRIEF SMALL CRAFT ADVISORY AT THE NEXT UPDATE. SIGNIFICANT SEAS WILL
BE RULED BY THE LOCALLY PRODUCED WIND DRIVEN SHORT PERIOD WAVES. AND
WITH AN OFFSHORE TRAJECTORY...A RANGE OF SEAS TO OCCUR. FRYING PAN
SHOALS WILL EXHIBIT WASHING MACHINE CONDITIONS...WITH LOCALLY HIGHER
WAVES LIKELY.
PREVIOUS DISCUSSION...............................................
AS OF 230 PM SATURDAY...AN EXERCISE CAUTION STATEMENT WAS RAISED FOR
EARLY SUNDAY TO ACCOUNT FOR THE PASSAGE OF A DRY COLD FRONT AND
ASSOCIATED GUSTY NW WINDS...MAINLY AROUND AND AFTER DAYBREAK. PRIOR
TO THIS...MANAGEABLE MARINE CONDITIONS TO PREVAIL WITH WEST WINDS
BECOMING WSW TO SW LATE TODAY AND TONIGHT AHEAD OF A WEAK BUT FAST
MOVING FRONT. SEAS WILL HOLD MAINLY IN A 2-4 FOOT RANGE HIGHEST
OFFSHORE...COMPOSED PRIMARILY OF SW WAVES OF 2-4 FEET RUNNING IN
INTERVALS OF 6-7 SECONDS. NEAR SHORE AND ICWW WATER TEMPERATURES
ARE IN THE LOWER 50S...AND A GOOD REMINDER THAT FLOTATION DEVICES
AND THERMAL WEAR CAN GO A LONG WAY IN ANY UNFORESEEN OCCURRENCE.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...NW WINDS WILL INCREASE SOME EARLY SUNDAY WITH
THE OFFSHORE EXIT OF A CLIPPER TYPE OF DISTURBANCE AT BOTH THE
SURFACE AND ALOFT. CAUTIONARY HEADLINES ARE NOT ANTICIPATED EVEN
WITH A LITTLE MIXING AS FORECAST SOUNDINGS SHOW NO HIGHER THAN 20
KNOTS THROUGH MOST OF WHAT SHOULD BE THE BOUNDARY LAYER OVER THE
MARINE ZONES...ESPECIALLY GIVEN THE COOLER SSTS OF THE NEARSHORE
WATERS. SUNDAY AFTERNOON WILL BRING A VEERING AND DECREASING WIND
REGIME AS HIGH PRESSURE BUILDS ACROSS VA AND THE GRADIENT EASES
LOCALLY. THIS SAME HIGH WILL ONLY SLOWLY MIGRATE EASTWARD FOR THE
REMAINDER OF THE SHORT TERM PERIOD ALL WHILE KEEPING A WEAK RIDGE
AXIS INTO THE COASTAL CAROLINAS. AS SUCH THE WINDS WILL REMAIN QUITE
LIGHT...GENERALLY 10KT...LEADING TO A MERE 2 FT WIND WAVE. AN
ADDITIONAL VEER TO A SOUTHERLY DIRECTION IS SLATED FOR MONDAY NIGHT
AS THE HIGH MOVES EVEN FURTHER OUT TO SEA AND A COLD FRONT REACHES
THE OH AND MS RIVER VALLEY REGIONS. AN INCREASE IN SPEED WILL ALSO
RESULT MONDAY NIGHT...GRADUALLY AT FIRST AND THEN WITH MORE VIGOR
AFTER ABOUT 06Z. SEAS COULD BUILD TO 5 FT ALONG THE EASTERN FRINGE
OF SOME OF THE ZONES NECESSITATING SCEC BUT A PEEK INTO THE LONG
TERM WOULD SUGGEST THAT A SMALL CRAFT ADVISORY WILL INSTEAD BE
HOISTED DUE TO FURTHER ANTICIPATED DETERIORATION OF CONDITIONS.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 230 PM SATURDAY...COLD FRONT APPROACHES THE WATERS ON TUESDAY
NIGHT INTO EARLY WEDNESDAY AND OFF THE COAST BY 12Z. TIGHT GRADIENT
WITH WINDS INCREASING FROM THE SW AT 20-25 KTS AHEAD OF FRONT WITH
SEAS BUILDING TO 5-7 FEET RESULTING IN SCA CRITERIA LATE TUESDAY
INTO MID DAY WEDNESDAY. ONCE FRONTS PASSES THE WINDS BACK FROM THE
SW TO WEST AND THEN BECOME MORE NORTHERLY BY 18Z WITH THE SEAS
DIMINISHING TO 3-5 FEET...2-4 FEET NEAR SHORE. WINDS WILL REMAIN
BRISK AT 15-20 KTS AND VEER TO THE NE ON THURSDAY BEFORE SLOWLY
DIMINISHING AS HIGH PRESSURE BUILDS ACROSS THE WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...DCH/MJC
SHORT TERM...MBB
LONG TERM...MAC
AVIATION...HDL
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
640 PM EST SAT JAN 14 2012
.SYNOPSIS...
A CLIPPER PASSES SOUTH TONIGHT. WARM UP EARLY NEXT WEEK. RAIN
SYSTEM MONDAY NIGHT AND TUESDAY. COLDER WEDNESDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
WEAK S/W EMBEDDED AN CHANNELED WESTERLY FLOW WILL TRAVERSE ACROSS
THE SOUTHERN COALFIELDS AND SOUTHWESTERN VA THIS EVENING. DYNAMICS
ASSOCIATED WITH THIS FEATURE QUITE MODEST...AND MOISTURE IS NOT TOO
ROBUST. CONDITIONS ARE FAVORABLE FOR A SHORT PERIOD SNOW SHOWERS
TO DEVELOP THIS EVENING.
BOTH NAM AND GFS IN PRETTY CLOSE AGREEMENT IN TIMING THE FEATURE
ACROSS FOR FORECAST AREA. BOTH MODELS HAVE BACKED OFF SLIGHTLY ON
QPF AMOUNTS FROM PREVIOUS RUNS. HOWEVER...SHORT TERM HRRR MODEL
STILL PAINTS SOME QPF IN THE FORM OF LIGHT SNOW OVER SW VA...AND
LESSER AMOUNTS OVER SRN COALFIELDS.
WILL CONTINUE WITH WSW FOR SW VA...KEEPING THE SAME GENERAL SNOW
AMOUNTS IN PLACE. HOWEVER...SINCE MODELS HAVE BACKED OFF SLIGHTLY
WITH AMOUNT OF MOISTURE AND UPSTREAM OBS AND SAT IMAGERY DO NOT SHOW
MUCH HAPPENING WITH THIS SHORTWAVE...HAVE BACKED OFF SLIGHTLY WITH
THE AREA COVERAGE OF SNOW ACCUMULATIONS FOR AREAS OUTSIDE THE
ADVISORY. USED ADJMETBC FOR PRIMARY TEMP FIELDS...WITH ADJUSTMENTS
OVER THE MOUNTAINS.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
QUIET START TO THE PERIOD WITH HIGH PRESSURE TRUDGING EAST SUNDAY
NIGHT. SOUTHWESTERLY FLOW KICKS IN WITH H925 WINDS INCREASING TO
30-40 KNOTS BY 12Z. THIS FLOW WILL START TO PUSH SOME HIGH CLOUDS
IN TOWARDS MORNING...OTHERWISE SKIES WILL BE MOSTLY CLEAR. THE
WINDS WILL ALSO BE PUSHING IN WARMER AIR ALOFT...H925 TEMPERATURES
RISE FROM -6C AT 00Z TO +6 AT 12Z. MODELS STILL HAVE A SHARP
INVERSION NEAR THE SURFACE THROUGH THE NIGHT. STILL...WITH SUCH
STRONG WINDS ALOFT...THINK SOME OF THE WARMER AIR WILL MIX DOWN AND
ALLOW FOR RISING TEMPERATURES OVERNIGHT. SO...WENT WITH A MIN TEMP
CLOSE TO THE MET AROUND MIDNIGHT...WITH A NONDIURNAL RISE THEREAFTER.
ECMWF DOES LOOK LIKE A GOOD MIDDLE-OF-THE-ROAD APPROACH TO NEXT
SYSTEM...WITH A GENERALLY LARGE MODEL SPREAD. LOW PRESSURE DEVELOPS
IN THE PLAINS ON MONDAY...AND THEN TAKES OFF TO THE NORTHEAST
TOWARDS YYZ BY 00Z WEDNESDAY. SUPPORT WILL BE PROVIDED BY DEEPENING
SHORTWAVE MOVING ACROSS THE NORTHERN PLAINS AND UPPER MISSISSIPPI
VALLEY. SOME ISENTROPIC LIFT NOTED ON MONDAY...MUCH OF WHICH WILL GO
INTO MOISTENING THE ATMOSPHERE AT FIRST AND INCREASING CLOUD COVER.
SUFFICIENTLY DEEP MOISTURE ARRIVES BY 18Z AND ALLOWS THE FIRST
RAINDROPS IN SOUTHEAST OHIO. PWAT CONTINUES TO INCREASE IN THE
SOUTHWEST FLOW...EVENTUALLY REACHING AN INCH OR SO BY 12Z TUESDAY.
POPS CONTINUE TO TREND UPWARD...REACHING THEIR PEAK BY 12Z TUESDAY
WITH CATEGORICAL VALUES ACROSS MUCH OF THE AREA. SUPPORT FOR LIFT
WILL BE PROVIDED BY LFQ OF H250 JET ALONG WITH CONTINUED 290/295K
ISENTROPIC UPGLIDE. STILL...RAIN RATES SHOULD NOT BE
EXCESSIVE...AND AROUND A HALF INCH OF RAIN CAN BE EXPECTED FROM THIS
EVENT THROUGH 12Z TUESDAY. RAN CLOSER TO MET NUMBERS MONDAY/MONDAY
NIGHT...WHICH HAD A SMALLER DIURNAL RANGE THAN THE MAV.
THEREAFTER...WE AWAIT COLD FROPA WHICH WILL OCCUR LATER TUESDAY
AFTERNOON AND TUESDAY EVENING. ANOTHER .20 TO .30 INCH OF RAIN IS
POSSIBLE IN CONTINUED MOIST FLOW/LIFT. UNCERTAINTY WITH TIMING
LEADS TO UNCERTAINTY IN CHANGEOVER TO SNOW...BUT FOR NOW THINK THIS
OCCURS AFTER 00Z WEDNESDAY. BY THAT TIME...DEEPER MOISTURE IS
DEPARTING AND ONLY HAVE LIKELY POPS ALONG WESTERN SLOPES...WITH
WINDS BEGINNING THE TRANSITION TO WESTERLY AND EVENTUALLY NORTHWEST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
SURFACE HIGH PRESSURE STARTS THIS PERIOD WITH COLD H85 TEMPS. AS
SYSTEM SWINGS SOUTHEAST ON THURSDAY...COULD SEE SOME LIGHT SNOW
SHOWERS FOR A BRIEF PERIOD OF TIME. AS THIS SYSTEM QUICKLY MOVES
NORTHEAST...ANOTHER IS ON ITS HEELS. BY THE END OF THE WEEK...THIS
SYSTEM SHOULD REACH THE OHIO VALLEY. HOWEVER THIS TIME...WARMER AIR
ACCOMPANIES IT. THIS WOULD LEAD TO RAIN. HPC GUIDANCE HANDLES THIS
WELL. WILL USE HPC WITH SOME MINOR ADJUSTMENTS.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
A BAND OF MOSTLY LIGHT SNOW WILL STREAK EAST THROUGH SOUTHWEST
VIRGINIA AND EXTREME SOUTHERN WEST VIRGINIA 00Z TO 06Z. CEILINGS
LOWERING TO 1 TO 2 THSD FT BKN AND VSBY AOB 3 MILES IN THE SNOW.
HAVE BECKLEY ON THE NORTHERN EDGE OF THE STEADY SNOW. SOME FLAKES
CAN STILL REACH THE GROUND FURTHER NORTH...INCLUDING THE HTS-CRW
CORRIDOR BUT THINKING NOT STEADY THERE.
CEILINGS AT 4 TO 8 THSD FT HTS TO CRW ON NORTH AT 00Z WILL TRY TO
LOWER INTO THE 2 TO 4 THSD FT BKN TO OVC 03Z TO 10Z...BEFORE
BECOMING SCATTERED FROM NW TO SE 12Z TO 15Z SUNDAY. VSBY MAY LOWER
BRIEFLY IN A BAND OF LIGHT SNOW HTS-CRW INTO THE 3 TO 5 MILE RANGE
THROUGH 06Z.
AFTER 15Z...SOME LINGERING STRATOCUMULUS CEILINGS AT 2 TO 3 THSD FT
OVER MOUNTAINOUS COUNTIES...SHOULD BECOME SCATTERED 18Z TO 21Z.
EXPECT JUST PATCHES OF MID DECK AOA 10 THSD FT THROUGHOUT FOR 21Z TO
00Z MONDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: NORTH OF THE SYNOPTIC LIGHT SNOW SYSTEM...
TIMING THE LOWERING OF CEILINGS TONIGHT AND THE SCATTERING OUT OF
THE STRATOCUMULUS ON SUNDAY MAY BE EITHER WAY...TOO SLOW OR
FAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EST 1HRLY 19 20 21 22 23 00 01 02 03 04 05 06
CRW CONSISTENCY M M M M M M M M M M M M
HTS CONSISTENCY M M M M M M M M M M M M
BKW CONSISTENCY M M M L L M M M M M M M
EKN CONSISTENCY M M M M M M L L L M M M
PKB CONSISTENCY H H H H H M M M M M M H
CKB CONSISTENCY M M M H M M M M M M M M
AFTER 00Z MONDAY...
IFR POSSIBLE IN SNOW SHOWERS TUESDAY NIGHT INTO EARLY WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...WINTER WEATHER ADVISORY UNTIL 7 AM EST SUNDAY FOR VAZ003-004.
&&
$$
SYNOPSIS...KMC/JB/CL
NEAR TERM...KMC
SHORT TERM...CL
LONG TERM...JB
AVIATION...KTB
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1145 PM CST THU JAN 12 2012
.UPDATE...FOR 06Z AVIATION DISCUSSION.
&&
.AVIATION...06Z AVIATION DISCUSSION.
UNCERTAINTIES...CEILING TRANSITION TIMINGS...SNOW SHWRS IMPACTS AND
TAPERING OFF TIMING...SFC WIND GUST POTENTIAL. SEVERAL ADMS POSSIBLE
THRU 14/06Z. BROAD UPPER LEVEL TROUGHING WILL CONTINUE TO MOVE NEWD
OF THE MID STATE BY 13/12Z...WITH MAIN IMPACTS OF SNOW SHWRS 13/06Z
-13/11Z....WITH MVFR CEILING FLUCTUATIONS. GUSTY SFC WINDS OF UP TO
25 KTS EXPECTED THRU 14/00Z PER STRONG SFC PRESSURE GRADIENT INFLUENCES.
CLING SKIES EXPECTED W TO E BETWEEN 13/16Z-13/18Z WITH SFC/UPPER LEVEL
RIDGING INFLUENCES PROVIDING ONLY POSSIBLE BKN CI THRU 14/06Z.
&&
.PREV DISCUSSION.../ISSUED 1115 PM CST THU JAN 12 2012/
UPDATE...
UPDATED WSW CODE AT BOTTOM. ZONES OUT SHORTLY.
PREV DISCUSSION.../ISSUED 1038 PM CST THU JAN 12 2012/
UPDATE...
MOSTLY LIGHT TO OCCASIONALLY MODERATE SNOW SHOWERS CONTINUE TO FALL
ACROSS PRIMARILY THE NORTHERN HALF OF THE MID STATE. UPON
EXAMINATION OF THE PAH RADAR...IT DOES LOOK AS THOUGH A DECREASE
IN COVERAGE AND INTENSITY IS INDICATED.
THE FORECAST LOOKS LIKE IT REMAINS ON TRACK. HOWEVER...WE WILL BE
EXTENDING THE WINTER WEATHER ADVISORY FOR THE CENTRAL AND NORTHERN
CUMBERLAND PLATEAU. SNOWFALL WILL LIKELY CONTINUE WELL PAST
MIDNIGHT ACROSS THAT AREA. THE WINTER WEATHER ADVISORY WILL EXPIRE
FOR THE PLATEAU AT 8 AM FRIDAY MORNING. ADDITIONAL ACCUMULATIONS
OF AROUND 1 INCH CAN BE EXPECTED.
OTW...WILL INCLUDE LOWER CHANCES OF MEASURABLE SNOW WEST OF THE
PLATEAU FOR THE AFTER MIDNIGHT PERIOD. FOR AREAS ADJACENT TO THE
PLATEAU...WILL KEEP 30-50 POPS RUNNING WITH 20 POPS FAR WEST.
MINIMAL ADDITIONAL ACCUMULATIONS ARE EXPECTED WEST OF THE PLATEAU
AFTER MIDNIGHT.
THIS AFD WILL BE REISSUED AROUND 11PM...ONCE THE NEW WSW IS
SENT...TO REFLECT THE PROPER WSW ZONE CODING AT THE BOTTOM OF THIS
MESSAGE.
PREV DISCUSSION... /ISSUED 826 PM CST THU JAN 12 2012/
UPDATED DISCUSSION...
SNOWFALL REPORTS CONTINUE TO TRICKLE IN THIS EVENING.
GENERALLY...ONE HALF TO ONE INCH AMOUNTS ACROSS THE FAR NORTHERN
TIER OF THE MID STATE. AREAS ALONG THE PLATEAU ARE ALSO SPORTING
ONE HALF TO 1 INCH AMOUNTS. RECENT RADAR TRENDS DID SHOW SOME
ENHANCEMENT MOVE ACROSS STEWART COUNTY AND WE DID GET A LOCAL
REPORT OF 1 TO 2 INCHES FOLLOWING THE BRIEF PERIOD OF HEAVIER
SNOWFALL.
OTW...LATEST RUC DATA STILL SHOWS THE SNOWFALL CUTTING OFF AROUND
06S TO THE WEST OF THE PLATEAU. LOOKING UPSTREAM...VSBYS ARE ALL
P6SM SO THIS IS LOOKING BELIEVABLE. FURTHERMORE...ECHO TRENDS
APPEARS TO BE WEAKENING TO OUR NORTHWEST.
RECEIVED A REPORT OF A 1 HOUR CLOSURE OF I-65 THROUGH MARSHALL
COUNTY DUE TO THE ROAD CONDITIONS. THUS...I HAVE UPDATED THE SPS TO
COVER ALL OF MIDDLE TN THROUGH THE OVERNIGHT. THE SPS WAS ISSUED
TO ADVISE OF THE DANGEROUS ROAD CONDITIONS DUE TO THE WINTRY PRECIP.
NO CHANGES TO THE ZONE FORECAST FOR NOW. I WILL UP THE SNOWFALL
GRIDS JUST BY ONE OR TWO TENTHS ACROSS THE STEWART COUNTY AREA.
OTW...EVERYTHING LOOKS OK FOR NOW.
PREV DISCUSSION... /ISSUED 553 PM CST THU JAN 12 2012/
DISCUSSION...
AREAS OF SNOWFALL CONTINUE AT THIS HOUR ACROSS MUCH OF THE
NORTHERN HALF OF MIDDLE TN. SCATTERED SNOW SHOWERS ARE ALSO NOTED
ACROSS SOUTHERN AREAS. SNOWFALL REPORTS ARE SCATTERED AND ARE
GENERALLY UNDER 1 INCH SO FAR.
FIRST ORDER OF BUSINESS WILL BE TO ALLOW THE WIND ADVISORY TO
EXPIRE AT 6PM CST. LATEST WIND REPORTS THROUGHOUT THE CWA ARE AT
THE SUB ADVISORY LEVEL. THUS...WITH THE WEAKENING GRADIENT TREND
EXPECTED TO CONTINUE...WILL ALLOW THE WIND ADVISORY TO EXPIRE.
SECOND ORDER OF BUSINESS WILL INVOLVE THE DECREASE IN ZONE
GROUPINGS ACROSS THE CWA. WILL DO THIS SO AS TO ALLOW THE ZONE
TEXT SNOWFALL AMOUNTS TO MATCH THE GRAPHICS AND WSW THAT IS
CURRENTLY IN EFFECT.
AS OF NOW EXPECTED SNOWFALL TOTALS...SNOWFALL GRAPHIC AND THE CURRENT
WSW APPEARS TO BE ON TRACK. WILL ADJUST ZONES TO MATCH.
OTW...MUCH LESS SNOWFALL COVERAGE IS NOTED ON THE MEG RADAR. THIS
WILL LIKELY CALL FOR PRE MIDNIGHT WORDING IN TERMS OF OUR SNOWFALL
POTENTIAL. THE 6HR QPF RETURNS FROM THE MODELS LOOK TO CUT OFF
THE SNOWFALL TO THE WEST OF THE CUMBERLAND PLATEAU. THIS WILL NEED
TO BE REFLECTED IN THE UPCOMING UPDATE.
I WILL ALSO POINT OUT THAT AN SPS HAS BEEN ISSUED TO TO ADVISE THE
MID STATE AREA OF THE DANGEROUS ROAD CONDITIONS THAT ARE IN PLACE.
THOUGH THE ACCUMULATION POTENTIAL WILL LESSEN WITH TIME
OVERNIGHT...THE ROAD CONDITIONS MAY IN FACT WORSEN.
THAT`S ALL FOR NOW...I`LL FIRST UPDATE THE GRIDS AND THEN RUN THE
FORMATTERS. ZONES WILL THEN FOLLOW SHORTLY.
PREV DISCUSSION... /ISSUED 259 PM CST THU JAN 12 2012/
DISCUSSION...SURFACE MAP AT 21Z SHOWS COLD FRONT COMPLETELY
THROUGH MIDDLE TENNESSEE, WITH RAPID COLD ADVECTION TAKING PLACE
ACROSS THE MID STATE. HAVE ALREADY RECEIVED SEVERAL REPORTS OF
LIGHT SNOW AND ICE, MAINLY ON THE NORTH SIDE OF I-40. DEEPEST
MOISTURE HAS ALREADY PULLED EAST OF THE MID STATE, WITH REMAINING
MOISTURE CONFINED TO THE LOWEST 10 KFT. LATEST MODELS SHOW LOW-
LEVEL WRAP-AROUND MOISTURE CONTINUING TO CIRCULATE THROUGH THE MID
STATE OVERNIGHT AND EARLY TOMORROW MORNING. QPF`S ARE RELATIVELY
LOW, WITH THE HIGHEST AMOUNTS OCCURRING ALONG THE UPPER PLATEAU,
TAPERING OFF TO NEAR ZERO IN OUR SOUTHWEST. SNOW AMOUNTS UP TO AN
INCH ARE POSSIBLE ALONG THE HIGHLAND RIM AND AREAS JUST WEST OF
THE CUMBERLAND PLATEAU, WITH 1 TO 2 INCHES POSSIBLE ALONG THE
PLATEAU ITSELF. SNOW WILL TAPER OFF SIGNIFICANTLY AFTER MIDNIGHT,
SO WILL CONTINUE THE WSW UNTIL 06Z TONIGHT. TEMPERATURES WILL
CONTINUE THEIR FREE-FALL OVERNIGHT, DROPPING BELOW 20 DEGREES IN
MANY PLACES. THUS, WHATEVER PRECIPITATION DOES FALL LATE THIS
AFTERNOON AND OVERNIGHT WILL LIKELY FREEZE AND STAY FROZEN UNTIL
TOMORROW.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
TNZ005>009-028>030-063-064-077>080.
WINTER WEATHER ADVISORY UNTIL 9 AM CST FRIDAY FOR TNZ010-011-
031>034-065-066.
&&
$$
31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1115 PM CST THU JAN 12 2012
.UPDATE...
UPDATED WSW CODE AT BOTTOM. ZONES OUT SHORTLY.
&&
.PREV DISCUSSION... /ISSUED 1038 PM CST THU JAN 12 2012/
UPDATE...
MOSTLY LIGHT TO OCCASIONALLY MODERATE SNOW SHOWERS CONTINUE TO FALL
ACROSS PRIMARILY THE NORTHERN HALF OF THE MID STATE. UPON
EXAMINATION OF THE PAH RADAR...IT DOES LOOK AS THOUGH A DECREASE
IN COVERAGE AND INTENSITY IS INDICATED.
THE FORECAST LOOKS LIKE IT REMAINS ON TRACK. HOWEVER...WE WILL BE
EXTENDING THE WINTER WEATHER ADVISORY FOR THE CENTRAL AND NORTHERN
CUMBERLAND PLATEAU. SNOWFALL WILL LIKELY CONTINUE WELL PAST
MIDNIGHT ACROSS THAT AREA. THE WINTER WEATHER ADVISORY WILL EXPIRE
FOR THE PLATEAU AT 8 AM FRIDAY MORNING. ADDITIONAL ACCUMULATIONS
OF AROUND 1 INCH CAN BE EXPECTED.
OTW...WILL INCLUDE LOWER CHANCES OF MEASURABLE SNOW WEST OF THE
PLATEAU FOR THE AFTER MIDNIGHT PERIOD. FOR AREAS ADJACENT TO THE
PLATEAU...WILL KEEP 30-50 POPS RUNNING WITH 20 POPS FAR WEST.
MINIMAL ADDITIONAL ACCUMULATIONS ARE EXPECTED WEST OF THE PLATEAU
AFTER MIDNIGHT.
THIS AFD WILL BE REISSUED AROUND 11PM...ONCE THE NEW WSW IS
SENT...TO REFLECT THE PROPER WSW ZONE CODING AT THE BOTTOM OF THIS
MESSAGE.
PREV DISCUSSION... /ISSUED 826 PM CST THU JAN 12 2012/
UPDATED DISCUSSION...
SNOWFALL REPORTS CONTINUE TO TRICKLE IN THIS EVENING.
GENERALLY...ONE HALF TO ONE INCH AMOUNTS ACROSS THE FAR NORTHERN
TIER OF THE MID STATE. AREAS ALONG THE PLATEAU ARE ALSO SPORTING
ONE HALF TO 1 INCH AMOUNTS. RECENT RADAR TRENDS DID SHOW SOME
ENHANCEMENT MOVE ACROSS STEWART COUNTY AND WE DID GET A LOCAL
REPORT OF 1 TO 2 INCHES FOLLOWING THE BRIEF PERIOD OF HEAVIER
SNOWFALL.
OTW...LATEST RUC DATA STILL SHOWS THE SNOWFALL CUTTING OFF AROUND
06S TO THE WEST OF THE PLATEAU. LOOKING UPSTREAM...VSBYS ARE ALL
P6SM SO THIS IS LOOKING BELIEVABLE. FURTHERMORE...ECHO TRENDS
APPEARS TO BE WEAKENING TO OUR NORTHWEST.
RECEIVED A REPORT OF A 1 HOUR CLOSURE OF I-65 THROUGH MARSHALL
COUNTY DUE TO THE ROAD CONDITIONS. THUS...I HAVE UPDATED THE SPS TO
COVER ALL OF MIDDLE TN THROUGH THE OVERNIGHT. THE SPS WAS ISSUED
TO ADVISE OF THE DANGEROUS ROAD CONDITIONS DUE TO THE WINTRY PRECIP.
NO CHANGES TO THE ZONE FORECAST FOR NOW. I WILL UP THE SNOWFALL
GRIDS JUST BY ONE OR TWO TENTHS ACROSS THE STEWART COUNTY AREA.
OTW...EVERYTHING LOOKS OK FOR NOW.
PREV DISCUSSION... /ISSUED 553 PM CST THU JAN 12 2012/
DISCUSSION...
AREAS OF SNOWFALL CONTINUE AT THIS HOUR ACROSS MUCH OF THE
NORTHERN HALF OF MIDDLE TN. SCATTERED SNOW SHOWERS ARE ALSO NOTED
ACROSS SOUTHERN AREAS. SNOWFALL REPORTS ARE SCATTERED AND ARE
GENERALLY UNDER 1 INCH SO FAR.
FIRST ORDER OF BUSINESS WILL BE TO ALLOW THE WIND ADVISORY TO
EXPIRE AT 6PM CST. LATEST WIND REPORTS THROUGHOUT THE CWA ARE AT
THE SUB ADVISORY LEVEL. THUS...WITH THE WEAKENING GRADIENT TREND
EXPECTED TO CONTINUE...WILL ALLOW THE WIND ADVISORY TO EXPIRE.
SECOND ORDER OF BUSINESS WILL INVOLVE THE DECREASE IN ZONE
GROUPINGS ACROSS THE CWA. WILL DO THIS SO AS TO ALLOW THE ZONE
TEXT SNOWFALL AMOUNTS TO MATCH THE GRAPHICS AND WSW THAT IS
CURRENTLY IN EFFECT.
AS OF NOW EXPECTED SNOWFALL TOTALS...SNOWFALL GRAPHIC AND THE CURRENT
WSW APPEARS TO BE ON TRACK. WILL ADJUST ZONES TO MATCH.
OTW...MUCH LESS SNOWFALL COVERAGE IS NOTED ON THE MEG RADAR. THIS
WILL LIKELY CALL FOR PRE MIDNIGHT WORDING IN TERMS OF OUR SNOWFALL
POTENTIAL. THE 6HR QPF RETURNS FROM THE MODELS LOOK TO CUT OFF
THE SNOWFALL TO THE WEST OF THE CUMBERLAND PLATEAU. THIS WILL NEED
TO BE REFLECTED IN THE UPCOMING UPDATE.
I WILL ALSO POINT OUT THAT AN SPS HAS BEEN ISSUED TO TO ADVISE THE
MID STATE AREA OF THE DANGEROUS ROAD CONDITIONS THAT ARE IN PLACE.
THOUGH THE ACCUMULATION POTENTIAL WILL LESSEN WITH TIME
OVERNIGHT...THE ROAD CONDITIONS MAY IN FACT WORSEN.
THAT`S ALL FOR NOW...I`LL FIRST UPDATE THE GRIDS AND THEN RUN THE
FORMATTERS. ZONES WILL THEN FOLLOW SHORTLY.
PREV DISCUSSION... /ISSUED 259 PM CST THU JAN 12 2012/
DISCUSSION...SURFACE MAP AT 21Z SHOWS COLD FRONT COMPLETELY
THROUGH MIDDLE TENNESSEE, WITH RAPID COLD ADVECTION TAKING PLACE
ACROSS THE MID STATE. HAVE ALREADY RECEIVED SEVERAL REPORTS OF
LIGHT SNOW AND ICE, MAINLY ON THE NORTH SIDE OF I-40. DEEPEST
MOISTURE HAS ALREADY PULLED EAST OF THE MID STATE, WITH REMAINING
MOISTURE CONFINED TO THE LOWEST 10 KFT. LATEST MODELS SHOW LOW-
LEVEL WRAP-AROUND MOISTURE CONTINUING TO CIRCULATE THROUGH THE MID
STATE OVERNIGHT AND EARLY TOMORROW MORNING. QPF`S ARE RELATIVELY
LOW, WITH THE HIGHEST AMOUNTS OCCURRING ALONG THE UPPER PLATEAU,
TAPERING OFF TO NEAR ZERO IN OUR SOUTHWEST. SNOW AMOUNTS UP TO AN
INCH ARE POSSIBLE ALONG THE HIGHLAND RIM AND AREAS JUST WEST OF
THE CUMBERLAND PLATEAU, WITH 1 TO 2 INCHES POSSIBLE ALONG THE
PLATEAU ITSELF. SNOW WILL TAPER OFF SIGNIFICANTLY AFTER MIDNIGHT,
SO WILL CONTINUE THE WSW UNTIL 06Z TONIGHT. TEMPERATURES WILL
CONTINUE THEIR FREE-FALL OVERNIGHT, DROPPING BELOW 20 DEGREES IN
MANY PLACES. THUS, WHATEVER PRECIPITATION DOES FALL LATE THIS
AFTERNOON AND OVERNIGHT WILL LIKELY FREEZE AND STAY FROZEN UNTIL
TOMORROW.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
TNZ005>009-028>030-063-064-077>080.
WINTER WEATHER ADVISORY UNTIL 9 AM CST FRIDAY FOR TNZ010-011-
031>034-065-066.
&&
$$
21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1038 PM CST THU JAN 12 2012
.UPDATE...
MOSTLY LIGHT TO OCCASIONALLY MODERATE SNOW SHOWERS CONTINUE TO FALL
ACROSS PRIMARILY THE NORTHERN HALF OF THE MID STATE. UPON
EXAMINATION OF THE PAH RADAR...IT DOES LOOK AS THOUGH A DECREASE
IN COVERAGE AND INTENSITY IS INDICATED.
THE FORECAST LOOKS LIKE IT REMAINS ON TRACK. HOWEVER...WE WILL BE
EXTENDING THE WINTER WEATHER ADVISORY FOR THE CENTRAL AND NORTHERN
CUMBERLAND PLATEAU. SNOWFALL WILL LIKELY CONTINUE WELL PAST
MIDNIGHT ACROSS THAT AREA. THE WINTER WEATHER ADVISORY WILL EXPIRE
FOR THE PLATEAU AT 8 AM FRIDAY MORNING. ADDITIONAL ACCUMULATIONS
OF AROUND 1 INCH CAN BE EXPECTED.
OTW...WILL INCLUDE LOWER CHANCES OF MEASURABLE SNOW WEST OF THE
PLATEAU FOR THE AFTER MIDNIGHT PERIOD. FOR AREAS ADJACENT TO THE
PLATEAU...WILL KEEP 30-50 POPS RUNNING WITH 20 POPS FAR WEST.
MINIMAL ADDITIONAL ACCUMULATIONS ARE EXPECTED WEST OF THE PLATEAU
AFTER MIDNIGHT.
THIS AFD WILL BE REISSUED AROUND 11PM...ONCE THE NEW WSW IS
SENT...TO REFLECT THE PROPER WSW ZONE CODING AT THE BOTTOM OF THIS
MESSAGE.
&&
.PREV DISCUSSION... /ISSUED 826 PM CST THU JAN 12 2012/
UPDATED DISCUSSION...
SNOWFALL REPORTS CONTINUE TO TRICKLE IN THIS EVENING.
GENERALLY...ONE HALF TO ONE INCH AMOUNTS ACROSS THE FAR NORTHERN
TIER OF THE MID STATE. AREAS ALONG THE PLATEAU ARE ALSO SPORTING
ONE HALF TO 1 INCH AMOUNTS. RECENT RADAR TRENDS DID SHOW SOME
ENHANCEMENT MOVE ACROSS STEWART COUNTY AND WE DID GET A LOCAL
REPORT OF 1 TO 2 INCHES FOLLOWING THE BRIEF PERIOD OF HEAVIER
SNOWFALL.
OTW...LATEST RUC DATA STILL SHOWS THE SNOWFALL CUTTING OFF AROUND
06S TO THE WEST OF THE PLATEAU. LOOKING UPSTREAM...VSBYS ARE ALL
P6SM SO THIS IS LOOKING BELIEVABLE. FURTHERMORE...ECHO TRENDS
APPEARS TO BE WEAKENING TO OUR NORTHWEST.
RECEIVED A REPORT OF A 1 HOUR CLOSURE OF I-65 THROUGH MARSHALL
COUNTY DUE TO THE ROAD CONDITIONS. THUS...I HAVE UPDATED THE SPS TO
COVER ALL OF MIDDLE TN THROUGH THE OVERNIGHT. THE SPS WAS ISSUED
TO ADVISE OF THE DANGEROUS ROAD CONDITIONS DUE TO THE WINTRY PRECIP.
NO CHANGES TO THE ZONE FORECAST FOR NOW. I WILL UP THE SNOWFALL
GRIDS JUST BY ONE OR TWO TENTHS ACROSS THE STEWART COUNTY AREA.
OTW...EVERYTHING LOOKS OK FOR NOW.
PREV DISCUSSION... /ISSUED 553 PM CST THU JAN 12 2012/
DISCUSSION...
AREAS OF SNOWFALL CONTINUE AT THIS HOUR ACROSS MUCH OF THE
NORTHERN HALF OF MIDDLE TN. SCATTERED SNOW SHOWERS ARE ALSO NOTED
ACROSS SOUTHERN AREAS. SNOWFALL REPORTS ARE SCATTERED AND ARE
GENERALLY UNDER 1 INCH SO FAR.
FIRST ORDER OF BUSINESS WILL BE TO ALLOW THE WIND ADVISORY TO
EXPIRE AT 6PM CST. LATEST WIND REPORTS THROUGHOUT THE CWA ARE AT
THE SUB ADVISORY LEVEL. THUS...WITH THE WEAKENING GRADIENT TREND
EXPECTED TO CONTINUE...WILL ALLOW THE WIND ADVISORY TO EXPIRE.
SECOND ORDER OF BUSINESS WILL INVOLVE THE DECREASE IN ZONE
GROUPINGS ACROSS THE CWA. WILL DO THIS SO AS TO ALLOW THE ZONE
TEXT SNOWFALL AMOUNTS TO MATCH THE GRAPHICS AND WSW THAT IS
CURRENTLY IN EFFECT.
AS OF NOW EXPECTED SNOWFALL TOTALS...SNOWFALL GRAPHIC AND THE CURRENT
WSW APPEARS TO BE ON TRACK. WILL ADJUST ZONES TO MATCH.
OTW...MUCH LESS SNOWFALL COVERAGE IS NOTED ON THE MEG RADAR. THIS
WILL LIKELY CALL FOR PRE MIDNIGHT WORDING IN TERMS OF OUR SNOWFALL
POTENTIAL. THE 6HR QPF RETURNS FROM THE MODELS LOOK TO CUT OFF
THE SNOWFALL TO THE WEST OF THE CUMBERLAND PLATEAU. THIS WILL NEED
TO BE REFLECTED IN THE UPCOMING UPDATE.
I WILL ALSO POINT OUT THAT AN SPS HAS BEEN ISSUED TO TO ADVISE THE
MID STATE AREA OF THE DANGEROUS ROAD CONDITIONS THAT ARE IN PLACE.
THOUGH THE ACCUMULATION POTENTIAL WILL LESSEN WITH TIME
OVERNIGHT...THE ROAD CONDITIONS MAY IN FACT WORSEN.
THAT`S ALL FOR NOW...I`LL FIRST UPDATE THE GRIDS AND THEN RUN THE
FORMATTERS. ZONES WILL THEN FOLLOW SHORTLY.
PREV DISCUSSION... /ISSUED 259 PM CST THU JAN 12 2012/
DISCUSSION...SURFACE MAP AT 21Z SHOWS COLD FRONT COMPLETELY
THROUGH MIDDLE TENNESSEE, WITH RAPID COLD ADVECTION TAKING PLACE
ACROSS THE MID STATE. HAVE ALREADY RECEIVED SEVERAL REPORTS OF
LIGHT SNOW AND ICE, MAINLY ON THE NORTH SIDE OF I-40. DEEPEST
MOISTURE HAS ALREADY PULLED EAST OF THE MID STATE, WITH REMAINING
MOISTURE CONFINED TO THE LOWEST 10 KFT. LATEST MODELS SHOW LOW-
LEVEL WRAP-AROUND MOISTURE CONTINUING TO CIRCULATE THROUGH THE MID
STATE OVERNIGHT AND EARLY TOMORROW MORNING. QPF`S ARE RELATIVELY
LOW, WITH THE HIGHEST AMOUNTS OCCURRING ALONG THE UPPER PLATEAU,
TAPERING OFF TO NEAR ZERO IN OUR SOUTHWEST. SNOW AMOUNTS UP TO AN
INCH ARE POSSIBLE ALONG THE HIGHLAND RIM AND AREAS JUST WEST OF
THE CUMBERLAND PLATEAU, WITH 1 TO 2 INCHES POSSIBLE ALONG THE
PLATEAU ITSELF. SNOW WILL TAPER OFF SIGNIFICANTLY AFTER MIDNIGHT,
SO WILL CONTINUE THE WSW UNTIL 06Z TONIGHT. TEMPERATURES WILL
CONTINUE THEIR FREE-FALL OVERNIGHT, DROPPING BELOW 20 DEGREES IN
MANY PLACES. THUS, WHATEVER PRECIPITATION DOES FALL LATE THIS
AFTERNOON AND OVERNIGHT WILL LIKELY FREEZE AND STAY FROZEN UNTIL
TOMORROW.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
TNZ005>011-028>034-063>066-077>080.
&&
$$
21
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1020 PM EST SAT JAN 14 2012
.SYNOPSIS...
A CLIPPER SYSTEM MOVES ACROSS NORTH CAROLINA OVERNIGHT. HIGH PRESSURE WILL
BUILD ACROSS THE AREA SUNDAY AND OFFSHORE INTO MONDAY PROVIDING A
GRADUAL MODERATION IN TEMPERATURES FOR EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 1010 PM EST SATURDAY...
BANDING OF SNOW OCCURRING ACROSS TAZEWELL EAST INTO THE BLUE RIDGE
OF FLOYD/PATRICK COUNTY. HAVE INCREASED SNOW AMOUNTS TO ACCOUNT
FOR THIS PER THE LATEST HRRR WHICH IS HANDLING THIS WELL RIGHT NOW.
HAVE HAD A REPORT OF 3.5 INCHES IN TAZEWELL. COULD SEE ANOTHER
INCH OR 2 BEFORE IT TAPERS OFF...AS THE BACK EDGE OF THE SNOW
EXTENDS INTO ERN KY. MAY HAVE TO EXPAND ADVY EAST...BUT WITH SFC
LOW OVER WRN NC...THINK THE SNOW WILL BEGIN TO TAPER OFF. WILL
CONTINUE SPECIAL WX STATEMENTS OVERNIGHT FOR THE NON ADVISORY
AREAS...WHERE AN INCH TO TWO INCHES WILL OCCUR.
PLAYED LOW TEMPERATURES TONIGHT CLOSE TO THE ADJMAV WITH READINGS
FROM AROUND 10 DEGREES WITH SNOWPACK IN THE NORTHWEST MOUNTAINS TO
THE MID 20S IN THE SOUTHEAST. SNOW SHOWERS AND SNOW FLURRIES WILL
END QUICKLY SUNDAY...WITH UPPER RIDGE AND SFC HIGH BUILDING OVER
THE REGION. WENT WITH HIGHS ON SUNDAY FROM THE MID 20S IN THE
NORTHWEST TO THE LOWER 40S IN THE SOUTHEAST.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
AS OF 300 PM EST SATURDAY...
CHALLENGING PORTION OF THE FORECAST. HIGH PRESSURE ALTHOUGH LEAVING
SE WEST VA LATE SUNDAY NIGHT...SHOULD ALLOW DECOUPLING AND TEMPS TO
FALL NEAR DEWPOINT LEVELS. THIS WOULD PUT MOST SPOTS AT OR BELOW
GUIDANCE...ESPECIALLY THE SOUTHSIDE AND PIEDMONT WHERE HIGH PRESSURE
IS CENTERED AT 1Z/7A MONDAY. LAST FRAME OF RGEM SIMULATED SAT IMAGES
SHOWS AT LEAST THICK HIGH CLOUDS JUST THEN ENTERING THE SW QUARTER
OF OUR CWA ALSO AT THAT TIME...WITH A LATE SSW TO SW WIND DEVELOPING
LATE SUNDAY NIGHT. THUS...TEMPS MAY RISE LATE SUNDAY NIGHT ACROSS NW
NC AND EXTREME SW VA AFTER DECOUPLING EARLIER IN THE EVENING...BUT
WILL NOT TRY TO PUT THIS DETAIL IN THE HOURLY T GRIDS FOR NOW. WITH
THE CLOUDS THICKENING IN THE WEST MONDAY MORNING...AND THEN MOVING
EAST BY LATE DAY...TEMPS MAY HAVE A HARD TIME WARMING TO GUIDANCE
NUMBERS WITH MOSTLY CLOUDY SKIES AND A STEEP INVERSION IN PLACE WITH
H85 TEMPS UNLIKELY TO MIX TO THE SURFACE. CONSIDERING THIS
REGIME...MONDAY NIGHT`S FORECAST BECOMES ALL THE MORE
DIFFICULT...WITH TEMPS WARM ENOUGH ALOFT FOR RAIN...BUT RATHER LARGE
DEWPOINT DEPRESSION AND POSSIBLY SOME BROKEN CLOUD COVER...TEMPS
COULD FALL FAST IN THE SHELTERED VALLEYS WEST OF THE BLUE
RIDGE...FOR SOME POSSIBLE FREEZING RAIN...BEFORE TEMPS WARM AFTER
MIDNIGHT TO ABV FREEZING. DID HAVE TO PUT IN HOURLY T GRIDS FOR THIS
PERIOD...AS LESS CLOUDS IN THE EXTREME EAST MAY ALLOW THOSE PARTS TO
DECOUPLE AGAIN...WHEREAS TEMPS FALL INITIALLY IN SE WEST VA THEN
RISE SLIGHTLY AFTER MIDNIGHT. GROUND ALSO WILL BE RATHER COOL
CONSIDERING FEW DAY STRING OF MORE WINTERLIKE TEMPS INCLUDING LOWS IN
THE MID AND UPPER TEENS SUNDAY NIGHT. FOR NOW...COMBINED A SLT CHC
OF FREEZING RAIN FOR A FEW HOURS WITH REGULAR RAIN TO HIGHLIGHT THIS
THREAT. H85 TEMPS THEN AT 12Z/7A TUESDAY SITTING AROUND +6C SHOULD
EVEN WITH THE RAIN AROUND ALLOW TEMPS TO PUSH 60F EAST OF THE BLUE
RIDGE AND MAYBE EVEN ROANOKE TOO...WITH A DOWNSLOPING WIND AND WARM
SURGE AHEAD OF THE NEXT POTENT BAROCLINIC BOUNDARY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 300 PM EST SATURDAY...
A COLD FRONT WILL ROLL ACROSS THE REGION TUESDAY EVENING WITH RAIN
SHOWERS ENDING AROUND MIDNIGHT. VERY COLD AIR AND A TIGHT PRESSURE
GRADIENT WILL THEN BRING WINDY AND GUSTY CONDITIONS TO THE
AREA...ALONG WITH WESTERN UPSLOPE SNOW SHOWERS INTO WEDNESDAY
MORNING. THE WIND AND SNOW WILL BE BRIEF AS HIGH PRESSURE BUILDS
INTO THE REGION WEDNESDAY AFTERNOON. HIGH PRESSURE DRIFTS OFF THE
EAST COAST...WHILE A DISTURBANCE TRACKS OVER THE NORTHERN OHIO
VALLEY THURSDAY. THIS DISTURBANCE IS FAR ENOUGH AWAY FROM THE AREA
TO KEEP POPS LOW AND CONFIDED TO THE GREENBRIER VALLEY/ALLEGHANY
HIGHLANDS THURSDAY EVENING. ANOTHER DISTURBANCE IS EXPECTED TO TRACK
ACROSS THE OHIO VALLEY FRIDAY NIGHT AND SATURDAY. THIS DISTURBANCE
HAS PACIFIC ORIGIN AND WILL BE WARM WHEN IT ENTERS THE REGION.
COLD TEMPERATURES WILL HANG AROUND TUESDAY NIGHT INTO WEDNESDAY
NIGHT. AS THE CHILLY HIGH PRESSURE SYSTEM MOVES OFF THE COAST AND
ZONAL FLOW IS ESTABLISHED ON THURSDAY...TEMPERATURES WILL MODERATE
ABOVE NORMAL FRIDAY AND SATURDAY.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
AS OF 634 PM EST SATURDAY...
WILL SEE A PERIOD OF SNOW MOVING INTO BLF SHORTLY AND LOOK FOR
VSBYS/CIGS TO DROP TO MVFR OR WORSE. THE BAND OF SNOW LOOKS TO
FAVOR A CORRIDOR FROM BLF TO SOUTH OF BCB THIS EVENING. DANVILLE
EVEN COULD SEE FLURRIES SHORTLY AFTER MIDNIGHT BUT WITH MVFR
CIGS.
WILL KEEP THE MTNS WITH MVFR CIGS/VSBYS LATER THIS
EVENING/OVERNIGHT AND DROP ROA/LYH TO MVFR CIGS AFTER
MIDNIGHT...MORE AROUND THE 2500 FT TO 3500 FT RANGE.
THE SYSTEM PUSHES WELL EAST OF THE AREA DURING THE DAY SUNDAY AND
WILL SEE IMPROVEMENTS TO CIGS/VSBYS AS SNOW ENDS BY DAWN EXCEPT
SNOW FLURRIES IN BLF/LWB. LOOK FOR VFR AT ALL SITES IN THE 12Z-15Z
TIME FRAME.
GUSTY NORTHWEST WINDS ACROSS THE HIGHER TERRAIN MAY HINDER
AVIATION OPERATIONS TONIGHT.
EXPECT VFR UNDER HIGH PRESSURE ON MONDAY WITH ANOTHER FRONT
BRINGING ADDED CHANCES OF RAIN AND LOW CIGS BY TUESDAY. WITH
COLDER AIR COMING IN WEDNESDAY...MOUNTAINS SNOW SHOWERS AND SNOW
FLURRIES ARE POSSIBLE.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY UNTIL 9 AM EST SUNDAY FOR VAZ007-009-
010-012-015.
NC...WINTER WEATHER ADVISORY UNTIL 9 AM EST SUNDAY FOR NCZ001-018.
WV...WINTER WEATHER ADVISORY UNTIL 9 AM EST SUNDAY FOR WVZ042.
&&
$$
SYNOPSIS...PH
NEAR TERM...KK/PH/WP
SHORT TERM...KM
LONG TERM...RCS
AVIATION...KK/PH/WP
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
956 PM CST SAT JAN 14 2012
.UPDATE...HAVE MADE A COUPLE FUTILE ATTEMPS TO ADJUST SKY COVER AND
TEMPS THIS EVENING...BUT UNLESS CLOUDS INCREASE QUICKLY OVER FAR NE
WI...TEMPS WILL LIKELY DROP SEVERAL DEGREES BLO ZERO THERE. WHERE
CLOUDS HAVE ALREADY THICKENED OVER THE SW TWO-THIRDS OF THE CWA...
TEMPS HAVE GENERALLY REMAINED STEADY OR WARMED BACK INTO THE UPPER
SINGLE DIGITS/LOWER TEENS. MAY ALSO NEED TO CONSIDER WARMING
TEMPS MORE LATE TONIGHT... ESPECIALLY OVER C WI...SOME LLVL WAA IS
ANTICIPATED. CURRENT READINGS ARE IN THE UPPER TEENS OVER WSTRN
WI. MAY NEED TO TAKE ONE MORE STAB AT SKY COVER/TEMPS BEFORE
LEAVING AT 11 PM.
KIECKBUSCH
&&
.PREV DISCUSSION...ISSUED AT 551 PM CST SAT JAN 14 2012...
SHORT TERM...TONIGHT AND SUNDAY.
THE SURFACE PRESSURE PATTERN OVER THE REGION WAS CAUSING SOME
ISSUES IN THE SHORT TERM. 20Z ANALYSIS SHOWED WEAK LOW PRESSURE
OVER LAKE MICHIGAN...A WEAK RIDGE OVER WISCONSIN AND A TROUGH
ACROSS MINNESOTA.
CONVERGENCE OVER THE LAKE RESULTED IN A BAND OF LAKE EFFECT SNOW
SHOWERS THAT PUSHED WEST INTO DOOR COUNTY. THE 15Z RUC APPEARED TO
HAVE A DECENT HANDLE ON THE SITUATION AS IT WAS SHOWING QPF IN THE
EASTERN PART OF THE FORECAST AREA INTO THIS EVENING. WENT WITH
SOME POPS IN THE EAST FOR THE EVENING BUT DRY THERE AFTER 06Z.
NOT REALLY SURE WHAT WAS CAUSING THE LIGHT SNOW AND FLURRIES IN
CENTRAL WISCONSIN TODAY DIRECTLY UNDER THE SURFACE RIDGE...POSSIBLY
SOME WEAK SHORT WAVE ENERGY PASSING THROUGH THE STATE. THE
VISIBILITY IN SOME LOCATIONS WENT AS LOW AS 3 MILES WITH SNOW AT
TIMES.
ANOTHER AREA OF LIGHT SNOW...WITH VISIBILITIES BELOW 2 MILES...WAS
ASSOCIATED WITH A WARM FRONT ACROSS MINNESOTA...AND A SHEARED UPPER
LEVEL SHORT WAVE. MODELS HAD THE FRONT DECAYING...THE SHORT WAVE
ENERGY MOVING SOUTHEAST THIS EVENING AND HAD QPF DRYING UP BEFORE
REACHING THE FORECAST AREA. HAVE SOME SLIGHT CHANCE POPS FOR
CENTRAL WISCONSIN DURING THE EVENING...BUT NOTHING AFTER 06Z.
TIME/HEIGHT SECTIONS FROM MODELS HAD QUITE A BIT OF LOW LEVEL
MOISTURE WITH LITTLE LIFT LATE TONIGHT...MAINLY IN THE NORTH. SO
HAVE INCLUDED A SLIGHT CHANCE OF FREEZING DRIZZLE OR FLURRIES
THERE 06Z-12Z SUNDAY.
PLENTY OF CLOUDS TONIGHT...BUT THINK THAT TEMPERATURES SHOULD FALL
INTO THE SINGLE DIGITS IN MOST LOCATIONS. WARMER THAN NORMAL HIGHS
RETURN ON SUNDAY IN STRONG WARM ADVECTION AHEAD OF THE SURFACE
SYSTEM APPROACHING FROM THE WEST. MODELS STILL HAD PLENTY OF
CLOUDS SO DID NOT GO TOO MUCH ABOVE GUIDANCE HIGHS.
EXPECT WINDS TO STEADILY INCREASE DURING THE DAY ON SUNDAY AHEAD
OF THE APPROACHING SYSTEM.
LONG TERM...MONDAY THROUGH NEXT SATURDAY.
NOT MUCH CHANGE TO THE IDEA OF DEVELOPMENT OF HIGH AMPLITUDE
RIDGING OVER THE BERING STRAIT WITH NRN STREAM ENERGY DIGGING SE
THRU ALASKA/WRN CANADA. THIS RESULTS IN DEVELOPING BROAD UPPER
TROF ACROSS SRN CANADA/NRN CONUS. THE MEAN FLOW UNDER THIS TROF TO
BE NEAR ZONAL FROM THE US...BRINGING SEVERAL RELATIVELY WEAK
SYSTEMS ACROSS THE WRN GREAT LAKES.
AT BEGINNING OF PERIOD...LOW PRESSURE MOVES EAST INTO CNTRL
ONTARIO SUNDAY NGT AND DRAGS COLD FRONT INTO CNTRL WI BY 12Z MONDAY. IT
STILL APPEARS THAT GULF MOISTURE WILL NOT HAVE TIME TO REACH THE
FORECAST AREA PRIOR TO THE FRONTAL PASSAGE. FRONT EXISTS REGION BY
EARLY IN THE AFTERNOON...THEN SHORT WAVE TROF APPROACHES FROM THE W.
SNOW SHOULD DEVELOP ALONG TIGHT BAROCLINIC ZONE ACROSS THE AREA BY
EARLY TUESDAY. ALL MODELS IN GENERAL AGREEMENT WITH DEVELOPMENT OF SFC
WAVE ALONG THE FRONT. ACCUMULATIONS SHOULD BE GENERALLY
MINOR...LESS THAN 2 INCHES THRU TUE. SOME LAKE EFFECT LINGERS IN
LAKE SUPERIOR SNOW BELT OF FORECAST AREA INTO TUE NIGHT. MIDWEEK
TEMPS WILL BE BELOW NORM AS ARCTIC AIR BRIEFLY FINDS A HOME.
SMALL CHANCES FOR SNOW SHOWERS ACROSS AREA AS WEAK RIPPLES IN WNW
UPPER FLOW CONTINUE TO MOVE ALONG BAROCLINIC ZONE. BOTH THE 14/12Z
GFS AND ECMWF TARGET FRIDAY AS THE BEST SNOW CHANCE IN THE SECOND
HALF OF THE WEEK WITH SHORT WAVE TROF MOVING ACROSS MIDWEST AND
SURFACE LOW MOVING ACROSS S ILLINOIS.
&&
.AVIATION...MVFR CIGS HAVE ERODED RAPIDLY LATE THIS AFTERNOON...WITH
ONLY A THIN BAND REMAINING FROM LNL/EGV SOUTH-SOUTHEAST TO PCZ/OSH.
AREA OF LIGHT SNOW OVER EC/SE MN AND WC WI WAS WEAKENING...AND
DOUBT THAT MUCH MORE THAN FLURRIES WILL MAKE INTO OUR FORECAST
AREA LATER THIS EVG. HOWEVER...EXPECT THAT SOME MVFR CIGS WILL
MOVE BACK INTO NC/C WI AFTER MIDNIGHT...THEN SPREAD SLOWLY EAST
INTO NE/EC WI LATE TONIGHT/EARLY SUNDAY. VFR CONDITIONS SHOULD
RETURN TO NC/C WI BY MID MORNING...AND NE/EC WI BY EARLY AFTERNOON.
WILL NEED TO MONITOR FOR THE POTENTIAL FOR LLWS LATE SUNDAY
AFTERNOON AND EVENING...AS SSW WINDS INCREASE TO AROUND 40S KTS
ABOUT 1500 FT AGL. FOR NOW...WILL LEAVE OUT OF THE TAFS...AS WINDS
AND GUSTS WILL ALSO INCREASE NEAR THE SURFACE DURING THIS TIME
PERIOD.
KIECKBUSCH
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
551 PM CST SAT JAN 14 2012
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY.
THE SURFACE PRESSURE PATTERN OVER THE REGION WAS CAUSING SOME
ISSUES IN THE SHORT TERM. 20Z ANALYSIS SHOWED WEAK LOW PRESSURE
OVER LAKE MICHIGAN...A WEAK RIDGE OVER WISCONSIN AND A TROUGH
ACROSS MINNESOTA.
CONVERGENCE OVER THE LAKE RESULTED IN A BAND OF LAKE EFFECT SNOW
SHOWERS THAT PUSHED WEST INTO DOOR COUNTY. THE 15Z RUC APPEARED TO
HAVE A DECENT HANDLE ON THE SITUATION AS IT WAS SHOWING QPF IN THE
EASTERN PART OF THE FORECAST AREA INTO THIS EVENING. WENT WITH
SOME POPS IN THE EAST FOR THE EVENING BUT DRY THERE AFTER 06Z.
NOT REALLY SURE WHAT WAS CAUSING THE LIGHT SNOW AND FLURRIES IN
CENTRAL WISCONSIN TODAY DIRECTLY UNDER THE SURFACE RIDGE...POSSIBLY
SOME WEAK SHORT WAVE ENERGY PASSING THROUGH THE STATE. THE
VISIBILITY IN SOME LOCATIONS WENT AS LOW AS 3 MILES WITH SNOW AT
TIMES.
ANOTHER AREA OF LIGHT SNOW...WITH VISIBILITIES BELOW 2 MILES...WAS
ASSOCIATED WITH A WARM FRONT ACROSS MINNESOTA...AND A SHEARED UPPER
LEVEL SHORT WAVE. MODELS HAD THE FRONT DECAYING...THE SHORT WAVE
ENERGY MOVING SOUTHEAST THIS EVENING AND HAD QPF DRYING UP BEFORE
REACHING THE FORECAST AREA. HAVE SOME SLIGHT CHANCE POPS FOR
CENTRAL WISCONSIN DURING THE EVENING...BUT NOTHING AFTER 06Z.
TIME/HEIGHT SECTIONS FROM MODELS HAD QUITE A BIT OF LOW LEVEL
MOISTURE WITH LITTLE LIFT LATE TONIGHT...MAINLY IN THE NORTH. SO
HAVE INCLUDED A SLIGHT CHANCE OF FREEZING DRIZZLE OR FLURRIES
THERE 06Z-12Z SUNDAY.
PLENTY OF CLOUDS TONIGHT...BUT THINK THAT TEMPERATURES SHOULD FALL
INTO THE SINGLE DIGITS IN MOST LOCATIONS. WARMER THAN NORMAL HIGHS
RETURN ON SUNDAY IN STRONG WARM ADVECTION AHEAD OF THE SURFACE
SYSTEM APPROACHING FROM THE WEST. MODELS STILL HAD PLENTY OF
CLOUDS SO DID NOT GO TOO MUCH ABOVE GUIDANCE HIGHS.
EXPECT WINDS TO STEADILY INCREASE DURING THE DAY ON SUNDAY AHEAD
OF THE APPROACHING SYSTEM.
.LONG TERM...MONDAY THROUGH NEXT SATURDAY.
NOT MUCH CHANGE TO THE IDEA OF DEVELOPMENT OF HIGH AMPLITUDE
RIDGING OVER THE BERING STRAIT WITH NRN STREAM ENERGY DIGGING SE
THRU ALASKA/WRN CANADA. THIS RESULTS IN DEVELOPING BROAD UPPER
TROF ACROSS SRN CANADA/NRN CONUS. THE MEAN FLOW UNDER THIS TROF TO
BE NEAR ZONAL FROM THE US...BRINGING SEVERAL RELATIVELY WEAK
SYSTEMS ACROSS THE WRN GREAT LAKES.
AT BEGINNING OF PERIOD...LOW PRESSURE MOVES EAST INTO CNTRL
ONTARIO SUNDAY NGT AND DRAGS COLD FRONT INTO CNTRL WI BY 12Z MONDAY. IT
STILL APPEARS THAT GULF MOISTURE WILL NOT HAVE TIME TO REACH THE
FORECAST AREA PRIOR TO THE FRONTAL PASSAGE. FRONT EXISTS REGION BY
EARLY IN THE AFTERNOON...THEN SHORT WAVE TROF APPROACHES FROM THE W.
SNOW SHOULD DEVELOP ALONG TIGHT BAROCLINIC ZONE ACROSS THE AREA BY
EARLY TUESDAY. ALL MODELS IN GENERAL AGREEMENT WITH DEVELOPMENT OF SFC
WAVE ALONG THE FRONT. ACCUMULATIONS SHOULD BE GENERALLY
MINOR...LESS THAN 2 INCHES THRU TUE. SOME LAKE EFFECT LINGERS IN
LAKE SUPERIOR SNOW BELT OF FORECAST AREA INTO TUE NIGHT. MIDWEEK
TEMPS WILL BE BELOW NORM AS ARCTIC AIR BRIEFLY FINDS A HOME.
SMALL CHANCES FOR SNOW SHOWERS ACROSS AREA AS WEAK RIPPLES IN WNW
UPPER FLOW CONTINUE TO MOVE ALONG BAROCLINIC ZONE. BOTH THE 14/12Z
GFS AND ECMWF TARGET FRIDAY AS THE BEST SNOW CHANCE IN THE SECOND
HALF OF THE WEEK WITH SHORT WAVE TROF MOVING ACROSS MIDWEST AND
SURFACE LOW MOVING ACROSS S ILLINOIS.
&&
.AVIATION...MVFR CIGS HAVE ERODED RAPIDLY LATE THIS AFTERNOON...WITH
ONLY A THIN BAND REMAINING FROM LNL/EGV SOUTH-SOUTHEAST TO PCZ/OSH.
AREA OF LIGHT SNOW OVER EC/SE MN AND WC WI WAS WEAKENING...AND
DOUBT THAT MUCH MORE THAN FLURRIES WILL MAKE INTO OUR FORECAST
AREA LATER THIS EVG. HOWEVER...EXPECT THAT SOME MVFR CIGS WILL
MOVE BACK INTO NC/C WI AFTER MIDNIGHT...THEN SPREAD SLOWLY EAST
INTO NE/EC WI LATE TONIGHT/EARLY SUNDAY. VFR CONDITIONS SHOULD
RETURN TO NC/C WI BY MID MORNING...AND NE/EC WI BY EARLY AFTERNOON.
WILL NEED TO MONITOR FOR THE POTENTIAL FOR LLWS LATE SUNDAY
AFTERNOON AND EVENING...AS SSW WINDS INCREASE TO AROUND 40S KTS
ABOUT 1500 FT AGL. FOR NOW...WILL LEAVE OUT OF THE TAFS...AS WINDS
AND GUSTS WILL ALSO INCREASE NEAR THE SURFACE DURING THIS TIME
PERIOD.
KIECKBUSCH
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1151 PM CST SAT JAN 14 2012
.AVIATION...
LOW CLOUDS WITH MVFR TO VFR CIGS EXPECTED TO CONTINUE GRADUALLY
SHIFTING EWD OVRNGT AND EARLY SUN AM. AS CLOUDS THIN LATE
COULD SEE SOME MVFR FOG DEVELOP AT TERMINALS. GENERALLY EXPECTING
VFR CONDITIONS SUN WITH SLY WINDS BECOMING GUSTY AT 15-25 KTS
WITH LOCALLY HIGHER GUSTS POSSIBLE... AS PRESSURE GRADIENT TIGHTENS.
SOME MODEL GUIDANCE IS SHOWING LOW CLOUDS AND FOG WITH MVFR TO
IFR CONDITIONS DEVELOPING SUN EVE... BUT CONFIDENCE IS LOW. IN
ADDITION CONDITIONS APPEAR MORE FAVORABLE AT OR JUST BEYOND THE
END OF TAF CYCLE (06Z/16TH). DUE TO LOW CONFIDENCE HAVE GONE WITH
A MENTION OF SOME LOW CLOUDS WITH MVFR BASES BUT LEFT OUT CIGS.
SLY WINDS TO DIMINISH SOMEWHAT BUT REMAIN GUSTY AT 10-20 KTS.
&&
.PREV DISCUSSION... /ISSUED 330 PM CST SAT JAN 14 2012/
SYNOPSIS...
A COUPLE OF CLIPPER TYPE SYSTEMS WERE RESPONSIBLE FOR SOME LIGHT
SNOW OVER THE REGION THIS MORNING AND THIS AFTERNOON. THE SURFACE
LOW ASSOCIATED WITH ONE OF THE SYSTEM PASSED JUST TO OUR SOUTH THIS
MORNING SPREADING SOME LIGHT SNOW OVER THE SOUTHERN COUNTIES.
ANOTHER LOW WAS MOVING THOUGH NORTHERN MN EARLY THIS AFTERNOON WITH
A WARM FRONT EXTENDING SOUTH INTO WESTERN IOWA. SOME LIGHT SNOW AND
FLURRIES WERE OCCURRING JUST AHEAD OF THE FRONT. THE CLIPPER TYPE
SYSTEMS WERE EMBEDDED IN NORTHWEST FLOW BOUNDED BY A LARGE TROF OVER
THE GREAT LAKES AND OHIO VALLEY AND RIDGING OVER THE ROCKIES.
ANOTHER VIGOROUS S/W WAS MOVING INTO BRITISH COLUMBIA AND THE
PACIFIC NW WITH 200 METER 12 HOUR HEIGHT FALLS NOTED ON THE MORNING
500MB ANALYSIS.
SHORT TERM...TONIGHT AND SUNDAY...
THE NORTHERN MN LOW AND ITS ASSOCIATED WARM FRONT WEAKEN THIS
EVENING AS LOW LEVEL FLOW OVER THE CENTRAL AND NORTHERN PLAINS
BACKS AHEAD OF THE PACIFIC NW S/W AND ITS STRONGER SURFACE LOW
MOVING INTO SOUTHERN SASKATCHEWAN BY SUNDAY MORNING. THE LIGHT
SNOW AHEAD OF THE WARM FRONT HAS BEEN STEADILY WEAKENING AS IT
MOVED OVER CENTRAL IOWA THIS AFTERNOON. THE CONTINUATION OF THIS
WEAKENING TREND IS SUPPORTED BY LOW/MID LEVEL FGEN DECREASING
OVER IA AND BECOMING MORE FOCUSED TO OUR NORTH THIS EVENING.
RECENT HRRR RUNS ALSO SUPPORT A BETTER THREAT OF MEASURABLE SNOW
NORTH OF THE CWFA. HAVE CUT POPS BACK TO SLIGHT CHANCE AT MOST...AND
LIMITED THOSE TO THE NORTHEAST THIRD OF THE FORECAST AREA FOR THIS
EVENING. AFTER MIDNIGHT EXPECT PARTLY TO MOSTLY CLOUDY SKIES WITH
MID LEVEL WAA ADVECTION CLOUDS MOVING THROUGH THE AREA AS WELL AS
SOME CI SPREADING IN WITH THE FORECAST AREA IN THE VICINITY OF THE
RIGHT ENTRANCE REGION OF AN H3 JET STREAK FROM MN/WI INTO NRN IN
AT 12Z SUNDAY. SOME FLURRIES WERE CONSIDERED IN THE WEST WITH THE
MID LEVEL WAA...BUT PRESSURE CONDENSATION DEFICITS WERE QUITE HIGH
BELOW 400MB...SO OPTED NOT TO MENTION FLURRIES. TEMPERATURES WILL
BE DIFFICULT WITH THE SNOW COVER...LIGHT WINDS AND PATCHY NATURE
OF THE CLOUDS. ANY CLEARING WILL ALLOW TEMPERATURES TO PLUMMET
OVER THE NORTH. LATEST TIMING OF THE CENTRAL IA CLOUDS INTO/THROUGH
THE CWFA SUGGEST THEY WILL NOT REACH THE EASTERN COUNTIES UNTIL A FEW
HOURS AFTER SUNSET SO ALLOWED FOR A SIGNIFICANT DROP EARLY THIS
EVENING IN NW IL WITH MINS IN THE SINGLE DIGITS.
SUNDAY THE REGION WILL BE DOMINATED BY SOUTHERLY FLOW IN THE LOW
LEVELS AS THE NORTHERN PLAINS SURFACE LOW TRACKS ALONG THE CANADIAN
BORDER AND DRY WESTERLY MID LEVEL FLOW. THIS SHOULD GIVE THE REGION
PLENTY OF SUN. KEPT TEMPERATURES IN THIS REGIME JUST ABOVE GUIDANCE
IN THE SOUTH WHERE LITTLE SNOW COVER EXISTS WITH HIGHS IN THE LOW
40S. OVER THE SNOW COVERED NORTH WENT WITH HIGHS IN THE 30S.
DLF..
LONG TERM...SUNDAY NIGHT THROUGH NEXT SATURDAY...
SUNDAY NIGHT AND MONDAY...LATEST SUITE OF 12Z RUN MODELS IN
GENERALLY GOOD AGREEMENT THIS PERIOD OF SUGGESTING LEAD IMPULSE OF
PACIFIC NW WAVE ENERGY/SEEN CURRENTLY ON WATER VAPOR IMAGERY
ROTATING DOWN ALONG THE B.C. COAST/ TO RIDGE-RIDE NORTH OF THE U.S.
BORDER ACRS SOUTHERN CANADA AND ACRS JAMES BAY INTO MON. ASSOCIATED
SFC FRONT OFF THIS PASSING WAVE PROBABLY TO JUST MAKE IT ACRS
THE FAR NORTHWESTERN CWA BY 12Z...THUS PRE-FRONTAL WAA AND SOME
BOUNDARY LAYER MOISTURE INCREASE LATE AT NIGHT TO PRODUCE A STEADY
TO SLOW TEMP RISE TOWARD DAWN AND LOWS WILL BE FROM MID EVENING
THROUGH 3 AM CST. 50+ KT SOUTHWESTERLY LLJ TO REALLY WAA AND
PRODUCE A WARM WEDGE/INVERSION ALOFT IN THE H85-H7 MB LAYER BY
MONDAY. LIKE PREVIOUS SHIFT STATED...HIGHER DPTS ADVECTED IN AS
WELL AS SOME SNOW MELT JUICED BL TRAPPED UNDER BUILDING INVERSION TO
INDUCE LLVL STRATUS AND FOG LATE SUNDAY NIGHT INTO MON. STILL SOME
QUESTION ON SPEED OF THIS DEVELOPING/MOISTURE INCREASE AND SOME
RECENT SIGNALS OF THE LOW CLOUDS AND FOG REALLY DEVELOPING MORE
CLOSER TO MONDAY MORNING AS OPPOSED TO SUNDAY NIGHT. BUT WILL KEEP
FOG MENTION SUN NIGHT AND MONDAY. INCREASING LIFT AND MID LEVELS
REMAINING DRY ALOFT SUGGEST DRIZZLE GETTING WRUNG OUT OF THIS LLVL
CLOUD DECK...AND IF SFC TEMPS CAN/T CLIMB ABOVE FREEZING TIL DAWN
MONDAY...MAY BE SOME TROUBLE WITH FREEZING DRIZZLE ALONG AND
NORTH OF I-80 FRO AWHILE AND WILL MENTION IN THE ZONES. LOW CLOUDS
AND LLVL SATURATION MAY LIMIT SFC HEATING ENOUGH TO KEEP TEMPS AT
OR BELOW FREEZING UNTIL MID MON MORNING NORTH OF THE HWY 30 AREAS
AND WILL EXTEND FREEZING DRIZZLE MENTION IN THESE AREAS FOR MON
MORNING. FOG TO CONTINUE WELL INTO MON AS WELL. AS SFC BOUNDARY
SAGS AND STALLS OUT ACRS THE CWA PARALLEL TO MEAN SOUTHWESTERLY
STEERING FLOW ON MON...CONTINUED LLVL MOISTURE TRANSPORT AND
CONVERGENCE INTO THIS FEATURE MAY INCREASE/SATURATE MOISTURE
PROFILES DEEP ENOUGH FOR MORE OF A LIGHT RAIN FORMING ACRS MUCH OF
THE SOUTHEAST TWO THIRDS OF THE DVN CWA BY LATE MORNING AND INTO THE
AFTERNOON. THICK LLVL CLOUDS...FOG...SNOW MELT PROCESS...AND
SATURATION MAY LIMIT SFC HEATING WITH HIGHS MORE IN THE MID TO UPPER
30S IN THE SOUTH HALF AS OPPOSED TO MODEL GUIDANCE UPPER 30S TO LOWER
40S. TEMPS MAY ACTUALLY HAVE TROUBLE WARMING ABOVE 32 IN THE FAR
NORTHERN CWA/NORTH OF CID IA TO FREEPORT IL/ WHICH COULD EXTEND A
FREEZING DRIZZLE OR VERY LIGHT FREEZING RAIN SCENARIO WELL INTO THE
AFTERNOON IN THOSE AREAS. APPROACH OF MAIN UPPER TROF FROM THE
PACIFIC NW AND ACRS THE PLAINS COULD INDUCE SOME LLVL WAVE
DEVELOPMENT ALONG ON THE FRONT WHICH COULD EXTEND SOME PRECIP ALMOST
DEF ZONE STYLE IN THE EASTERN CWA MONDAY EVENING. WITH TOP-DOWN
COOLING AND SATURATION TAKING PLACE...THE RAIN COULD SWITCH OVER TO A
MIX OR ALL SNOW WITHIN A FEW HOURS AFTER SUNSET WITH SOME LIGHT
SLUSHY ACCUMULATION ALONG THE EASTERN I-80 CORRIDOR. TEMPS TO CRASH
LATE MON NIGHT INTO TUE MORNING IN LLVL COLD CONVEYOR WITH VALUES
RANGING FROM THE MID TEENS IN THE NORTHWEST...TO THE MID 20S IN THE
FAR EAST AND SOUTHEAST.
TUESDAY AND WEDNESDAY...THE LLVL CYCLONE REALLY TAKES OFF/DEEPENS
ACRS THE CENTRAL GRT LKS ON TUE...BUT THE BRUNT OF THE PASSING UPPER
TROF ACRS THE LOCAL AREA STILL TO PROBABLY TO MAKE FOR WIDESPREAD
LIGHT SNOWS ACRS MOST OF THE DVN CWA THROUGH LATE TUE AFTERNOON
BEFORE THE UPPER TROF AXIS PASSES ACRS LK MI BY TUE EVENING AND
SUBSIDENCE TAKES OVER IN ITS WAKE. POTENTIAL FOR SOME 1-2 INCH
AMOUNTS BY TUE EVENING MAINLY ALONG AND NORTH OF THE HWY 30
CORRIDOR...BUT MORE OF A STORY WILL BE THE COLD AND NORTHWESTERLY
SFC WINDS GUSTING UP OVER 30 MPH AT TIMES WITH WIND CHILLS NEAR
ZERO IN THE AFTERNOON. CLEARING AND COLD CONDITIONS TUE NIGHT WITH
PASSING LLVL RIDGE LOBE...SOME LOWS BELOW ZERO POSSIBLE IN AREAS
NORTH OF I80. PASSING CLIPPER ACRS MN/WI IN FRESHLY ESTABLISHED BROAD
NORTH-WESTERLIES...MAY USHER YET ANOTHER FRONT INTO THE CWA BY LATE
WED NIGHT WITH POSSIBLE FLURRIES.
THURSDAY THROUGH SATURDAY...LLVL BAROCLINICITY TO GET ALIGNED
PARALLEL UNDER THESE MEAN FLOW NORTH-WESTERLIES ACRS THE CWA ON
THU...AND ANY PASSING WAVE ALOFT IN THE PROGRESSIVE FLOW COULD WRING
OUT SOME LIGHT SNOW OR FLURRIES ALONG THE LLVL THERMAL RIBBON ON THU
AND WILL CARRY LOW CHC POPS FOR THIS POTENTIAL. BOTH THE 12Z RUN
GFS AND ECMWF NOW PICK UP ON A MORE SUBSTANTIAL TYPE CLIPPER-LIKE
WAVE PROPAGATING DOWN IN THIS FLOW ALONG THE BAROCLINICITY WHICH
UTILIZES SOME GULF MOISTURE FEED FROM THE SOUTH TO PRODUCE 1-3 OR
EVEN 2-4 INCHES OF SNOW ACRS THE NORTH HALF OF THE DVN CWA FROM LATE
THU NIGHT INTO FRI MORNING. WILL KEEP CHC POPS GOING FOR SNOW ON FRI
FOR NOW...AND MAYBE A MIX OF RAIN AND SNOW IN THE SOUTH WITH PRE-
SYSTEM WARM DRAW ALOFT POSSIBLE. FLATTENING FLOW AND POST-SYSTEM
RIDGING MAY BRING A LULL IN THE ACTION FOR LATER FRI NIGHT AND SAT.
SOME SIGNS OF ENOUGH WAA ON SAT AHEAD OF TE NEXT DEVELOPING LARGE
SYSTEM TO DRIVE TEMPS INTO THE MID TO UPPER 30S DEPENDING ON SNOW
COVER BY THAT TIME. ..12..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1011 PM MST SAT JAN 14 2012
.UPDATE...
959 PM MST SAT JAN 14 2012
JUST COMPLETED AN UPDATE. TIGHTER GRADIENT/LOW LEVEL JET HAS SET
UP OVER THE WESTERN PORTION OF THE AREA WITH WINDS NOW IN THE
BREEZY TO WINDY CATEGORY. THE LATEST RUC CATCHES ONTO THIS...AND
USED TO UPDATE THE WINDS. WITH THE WINDS STAYING UP STRONGER THAN
EXPECTED RAISED MINS A FEW DEGREES.
BULLER
&&
.DISCUSSION...
200 PM MST SAT JAN 14 2012
TONIGHT...QUIET WEATHER WILL PREVAIL THROUGH THE OVERNIGHT HOURS
WITH A GENERALLY CLEAR SKY. SOUTHWESTERLY WINDS WILL BECOME MORE
WESTERLY LATE TONIGHT AS A WEAK SURFACE TROUGH SLIDES THROUGH THE
AREA. OVERNIGHT TEMPS SHOULD GENERALLY BE IN THE MID 20S WHICH IS
AROUND 10 DEGREES ABOVE NORMAL.
FOLTZ
SUNDAY-TUESDAY NIGHT...TEMPERATURES IN THE UPPER 50S TO NEAR 65
EXPECTED SUNDAY (RECORD/NEAR RECORD HIGH POSSIBLE IN YUMA...63 IN
2006) AHEAD OF A COLD FRONT THAT MOVES THROUGH SUNDAY NIGHT.
DIFFERING SOLUTIONS AS TO WHETHER OR NOT THE FRONT CAN MOVE
THROUGH THE SOUTHWEST PORTIONS OF THE AREA WHERE IT MAY BECOME
STATIONARY TIL MONDAY AFTERNOON WHEN AN UPPER LEVEL DISTURBANCE
WITHIN NORTHWEST FLOW ALOFT MOVES THROUGH. AS IT DOES AM EXPECTING
THE FRONT TO THEN CLEAR THE AREA. 850 TEMPERATURES AS WELL AS
MOS/MAV AND BETTER OF LATE BIAS CORRECTED GRIDS WOULD SUPPORT
HIGHS IN THE 30S FOR ALL BUT THE WEST/SOUTHWEST PARTS OF THE AREA
MONDAY WHERE AHEAD OF THE FRONT HIGHS IN THE LOW TO MID 40S
EXPECTED.
AS FOR PRECIPITATION CHANCES...NAM/ECWMF IN BETTER AGREEMENT WHEN
COMPARED TO THE GFS (SLIGHTLY SLOWER) WITH REGARDS TO ARRIVAL AND
DEPARTURE OF ABOVE MENTIONED UPPER DISTURBANCE AND MOISTURE
ASSOCIATED WITH IT MONDAY NIGHT. GIVEN THE FAST FLOW ALOFT SHOULD
SEE ONLY A FEW TENTHS OF AN INCH OF SNOW FROM THIS SYSTEM. THINK
IT WILL ONLY BE A 6 HOUR OR SO EVENT BUT GIVEN THE TIMING
DIFFERENCES DECIDED TO EXTEND IT FOR THE ENTIRE NIGHT AND WILL
AWAIT FUTURE MODEL RUNS TO HOPEFULLY PIN IT DOWN A BIT BETTER.
SHOULD SEE LOTS OF SUN TUESDAY WITH WINDS GENERALLY UNDER 10 MPH.
BELOW NORMAL AFTERNOON HIGHS EXPECTED WITH MID 30S ACROSS THE
AREA. OVERNIGHT LOWS THROUGH THE PERIOD NOT FAR OFF FROM NORMAL.
WEDNESDAY THROUGH SATURDAY...FORECAST AREA TO REMAIN UNDER
NORTHWEST FLOW ALOFT. DRY THROUGH FRIDAY NIGHT WITH A SPOTTY
SLIGHT CHANCE FOR LIGHT RAIN SATURDAY AND A LITTLE BETTER CHANCE
EARLY SATURDAY NIGHT AS A WEATHER DISTURBANCE MOVES THROUGH.
TEMPERATURES THROUGH THE PERIOD START IN THE 40S
WEDNESDAY...QUICKLY WARMING INTO THE 50S THURSDAY-SATURDAY. MAY
SEE SOME 60S THURSDAY-SATURDAY...ESPECIALLY ALONG AND WEST OF THE
CO/KS BORDER PER 850 TEMPERATURES (AND MEX GUIDANCE) BUT FOR NOW
GIVEN GOOD AGREEMENT WITH SURROUNDING OFFICES WILL NOT MAKE ANY
CHANGES.
07
&&
.AVIATION...
1010 PM MST SAT JAN 14 2012
SURFACE HIGH PRESSURE WILL SLIDE INTO THE EASTERN CONUS AS A LEE
TROUGH DEVELOPS AND DEEPENS TO OUR WEST. IN THE UPPER
LEVELS...HIGH PRESSURE RIDGE WILL MOVE OVER THE AREA THIS PERIOD
WITH A TROUGH MOVING INTO THE INTERMOUNTAIN WEST. VFR CONDITIONS
ARE EXPECTED DURING THIS PERIOD WITH HIGH CIRRUS MOVING OVER THE
AREA FROM TIME TO TIME. SURFACE WINDS WILL BE FROM THE SOUTHWEST
EARLY THEN SWITCHING TO THE WEST. TOWARDS THE END OF THE
PERIOD...WINDS WILL BECOME LIGHT AND VARIABLE AS THE PRESSURE
GRADIENT WEAKENS.
BAS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1210 AM EST SUN JAN 15 2012
...Mesoscale Update...
Well we`re down to a few lingering flurries and that`s about it.
Will continue the WSW for road conditions, but no more meaningful
snow is expected.
Sky cover will be a challenge overnight, and will have a significant
impact on temperatures. NAM12 and GFS40 show skies becoming mostly
clear overnight, as they move the clouds northwest Illinois due
east. However the HRRR develops a very low stratus deck right over
the LMK CWA and keeps it there through the night. Satellite loops
indeed show a developing low cloud deck over central Kentucky and
Fort Knox reported a few clouds at 600 feet on their 11pm
observation. So, will continue with high-end partly/low-end mostly
cloudy skies for tonight.
Even with some cloud cover, the 1 to 4 inches of brand new snow will
cause temperatures to fall easily. Have decreased lows in relation
to the amount of snow we received earlier this evening. As a result
from Meade County to Garrard and Lincoln counties we have lows
progged in the 12 to 16 degree range. If clouds become thicker than
forecast then these lows will not be realized, but there should be
enough breaks to allow temps to fall at least into the teens. Calm
winds associated with high pressure moving in from the lower
Mississippi Valley to be centered right over Kentucky at 12Z will
assist.
&&
.Short Term (Tonight and Sunday)...
Well, looks like water vapor imagery has a pretty potent
clipper/shortwave crossing the TN/KY border, and shortwave energy
extending back up through IA/MN. An associated surface low is
located near PAH at the moment, with light snow occurring anywhere
form central IL towards west-central KY. However, ground truth
reports indicate that a lack of boundary layer moisture is keeping
the light snow from really doing too much at the moment, but it is
starting to hit the ground finally in our western CWA as several
mesoscale models had indicated the strengthening overhead. Thus,
will keep the advisory going for the time being, but will likely be
able to cancel part of the counties by the forecast package time.
Really think we`d be fine with a Special Weather Statement, but will
at least give the advisory a chance for our easternmost counties
anyway. Upslope for the Bluegrass region south of 64 and the Lake
Cumberland region may help yield small accumulations most likely
less than an inch. Will send another quick AFD update if counties
are cancelled. At the very least, have trended back POPs to the
chance category through 00z.
Regardless of the light snow amounts if any, the clipper system
should be east of our CWA by around midnight, so have tapering POPs
from northwest to southeast tonight, ending in flurries by 06z. With
the surface low/clipper passage this evening, we could see brief
gusty winds on the back side of the low, with 1-2 hours of gusts up
to 25 knots possibly. Surface high pressure will quickly move in,
and towards dawn Sunday, winds will be light/variable. Look for
overnight lows ranging from the upper teens to lower 20s.
For Sunday, clearing behind the clipper will allow our temperatures
to climb into the mid to upper 30s in most spots, perhaps the lower
40s over the far southwest closest to the upper ridging.
.Long Term (Sunday Night - Saturday)...
Sunday Night - Tuesday Night...
Surface high pressure and slight ridging aloft will shift to the
east coast states by late Sunday. Surface winds will become
southerly, while winds aloft will favor southwesterly, especially by
Monday morning. A shortwave and associated surface low will pass by
to our north, with the surface low positioned across the southern
Great Lakes by Tuesday morning. A cold front will be stretched
southwestward from the Great Lakes through the mid Mississippi River
Valley. Southerly winds will become rather breezy to locally windy
by Monday afternoon as the pressure gradient strengthens between the
east coast high and this approaching area of low pressure.
Additionally, isentropic lift will increase across the area, and by
Monday afternoon we should see scattered rain showers build across
the forecast area. The greatest precipitation chances continue be in
the north and northwest Monday afternoon into the evening, closest
to the frontal boundary.
The cold front will begin to push into the forecast area late Monday
night and exit the southeast CWA early Tuesday afternoon. This will
provide the best chance of widespread rain showers and a few rumbles
of thunder, as moisture streams northward from the open Gulf. PWATs
are still on track to reach, and slightly exceed, the one inch mark,
which will supply about a half an inch to an inch of rainfall for
most locations. Most likely areas for the higher amounts would be
across the north and west, where Monday afternoon rainfall will add
to the rainfall total.
As for temperatures, southerly winds should aid the warming process
Monday, but cloud cover and precipitation chances in the afternoon
could put a stop to that. Either way, upper 40s across the north to
lower 50s across the south look good at this time. Tuesday morning
lows should be rather mild for this time of year, with generally mid
40s expected. Temperatures should warm some ahead of the front
Tuesday, but will drop off once the front passes. Will continue with
the non-diurnal temps, with the warmest locations being across the
south and east. For now, will go with mid and upper 40s across the
northwest, with low to mid 50s across the southeast for highs
Tuesday. Could see a rain snow mix on the back side of departing
precipitation if cold air works in fast enough. The 12Z GFS came in
a little warmer at the surface and aloft than previous runs.
However, will not make too many changes to the ongoing forecast of
rain/snow mix Tuesday afternoon and night because the NAM and SREF
data continue to show cooler temps arriving. Lows Tuesday night will
drop to the low to mid 20s.
Wednesday - Saturday...
Surface high pressure behind the cold front will quickly move east,
with southerly flow commencing by late Wednesday. Flow aloft will
transition from northwesterly Wednesday to basically zonal by
Friday. High temperatures in the low to mid 30s Wednesday will give
way to 50s by Saturday. A clipper system will pass by to our north
Thursday, while our next best chance of precipitation will arrive
near the weekend. Another area of low pressure is forecast to swing
into the Ohio Valley Friday through Saturday. Moisture does not look
all that impressive at this time, but rain chances will increase
Friday afternoon and continue into Saturday with the cold frontal
passage.
&&
.Aviation (06Z TAF Issuance)...
Clipper that caused this afternoon/evening`s snowfall is quickly
racing east into the Carolina`s and precipitation has ended across
the region. Main concern for the overnight is potential for low
stratus development as very low level moisture lingers and will
combine with increasingly subsident airmass as high pressure builds
in. Best chances for a window of IFR or below stratus deck will be
at LEX and SDF through the predawn hours, however will stay
optimistic that BWG remains VFR through the remainder of the
forecast. Otherwise, light northwest winds overnight will veer to
southeasterly between 5 and 10 mph this afternoon. High pressure at
the surface and aloft will keep the forecast VFR through the day.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
INZ090>092.
KY...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
KYZ025-028>031-034-038>041-045>049-054>057-066-067.
$$
Mesoscale........13
Short Term.......AL
Long Term........MJP
Aviation.........BJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1142 PM EST SAT JAN 14 2012
...Mesoscale Update...
Well we`re down to a few lingering flurries and that`s about it.
Will continue the WSW for road conditions, but no more meaningful
snow is expected.
Sky cover will be a challenge overnight, and will have a significant
impact on temperatures. NAM12 and GFS40 show skies becoming mostly
clear overnight, as they move the clouds northwest Illinois due
east. However the HRRR develops a very low stratus deck right over
the LMK CWA and keeps it there through the night. Satellite loops
indeed show a developing low cloud deck over central Kentucky and
Fort Knox reported a few clouds at 600 feet on their 11pm
observation. So, will continue with high-end partly/low-end mostly
cloudy skies for tonight.
Even with some cloud cover, the 1 to 4 inches of brand new snow will
cause temperatures to fall easily. Have decreased lows in relation
to the amount of snow we received earlier this evening. As a result
from Meade County to Garrard and Lincoln counties we have lows
progged in the 12 to 16 degree range. If clouds become thicker than
forecast then these lows will not be realized, but there should be
enough breaks to allow temps to fall at least into the teens. Calm
winds associated with high pressure moving in from the lower
Mississippi Valley to be centered right over Kentucky at 12Z will
assist.
&&
.Short Term (Tonight and Sunday)...
Well, looks like water vapor imagery has a pretty potent
clipper/shortwave crossing the TN/KY border, and shortwave energy
extending back up through IA/MN. An associated surface low is
located near PAH at the moment, with light snow occurring anywhere
form central IL towards west-central KY. However, ground truth
reports indicate that a lack of boundary layer moisture is keeping
the light snow from really doing too much at the moment, but it is
starting to hit the ground finally in our western CWA as several
mesoscale models had indicated the strengthening overhead. Thus,
will keep the advisory going for the time being, but will likely be
able to cancel part of the counties by the forecast package time.
Really think we`d be fine with a Special Weather Statement, but will
at least give the advisory a chance for our easternmost counties
anyway. Upslope for the Bluegrass region south of 64 and the Lake
Cumberland region may help yield small accumulations most likely
less than an inch. Will send another quick AFD update if counties
are cancelled. At the very least, have trended back POPs to the
chance category through 00z.
Regardless of the light snow amounts if any, the clipper system
should be east of our CWA by around midnight, so have tapering POPs
from northwest to southeast tonight, ending in flurries by 06z. With
the surface low/clipper passage this evening, we could see brief
gusty winds on the back side of the low, with 1-2 hours of gusts up
to 25 knots possibly. Surface high pressure will quickly move in,
and towards dawn Sunday, winds will be light/variable. Look for
overnight lows ranging from the upper teens to lower 20s.
For Sunday, clearing behind the clipper will allow our temperatures
to climb into the mid to upper 30s in most spots, perhaps the lower
40s over the far southwest closest to the upper ridging.
.Long Term (Sunday Night - Saturday)...
Sunday Night - Tuesday Night...
Surface high pressure and slight ridging aloft will shift to the
east coast states by late Sunday. Surface winds will become
southerly, while winds aloft will favor southwesterly, especially by
Monday morning. A shortwave and associated surface low will pass by
to our north, with the surface low positioned across the southern
Great Lakes by Tuesday morning. A cold front will be stretched
southwestward from the Great Lakes through the mid Mississippi River
Valley. Southerly winds will become rather breezy to locally windy
by Monday afternoon as the pressure gradient strengthens between the
east coast high and this approaching area of low pressure.
Additionally, isentropic lift will increase across the area, and by
Monday afternoon we should see scattered rain showers build across
the forecast area. The greatest precipitation chances continue be in
the north and northwest Monday afternoon into the evening, closest
to the frontal boundary.
The cold front will begin to push into the forecast area late Monday
night and exit the southeast CWA early Tuesday afternoon. This will
provide the best chance of widespread rain showers and a few rumbles
of thunder, as moisture streams northward from the open Gulf. PWATs
are still on track to reach, and slightly exceed, the one inch mark,
which will supply about a half an inch to an inch of rainfall for
most locations. Most likely areas for the higher amounts would be
across the north and west, where Monday afternoon rainfall will add
to the rainfall total.
As for temperatures, southerly winds should aid the warming process
Monday, but cloud cover and precipitation chances in the afternoon
could put a stop to that. Either way, upper 40s across the north to
lower 50s across the south look good at this time. Tuesday morning
lows should be rather mild for this time of year, with generally mid
40s expected. Temperatures should warm some ahead of the front
Tuesday, but will drop off once the front passes. Will continue with
the non-diurnal temps, with the warmest locations being across the
south and east. For now, will go with mid and upper 40s across the
northwest, with low to mid 50s across the southeast for highs
Tuesday. Could see a rain snow mix on the back side of departing
precipitation if cold air works in fast enough. The 12Z GFS came in
a little warmer at the surface and aloft than previous runs.
However, will not make too many changes to the ongoing forecast of
rain/snow mix Tuesday afternoon and night because the NAM and SREF
data continue to show cooler temps arriving. Lows Tuesday night will
drop to the low to mid 20s.
Wednesday - Saturday...
Surface high pressure behind the cold front will quickly move east,
with southerly flow commencing by late Wednesday. Flow aloft will
transition from northwesterly Wednesday to basically zonal by
Friday. High temperatures in the low to mid 30s Wednesday will give
way to 50s by Saturday. A clipper system will pass by to our north
Thursday, while our next best chance of precipitation will arrive
near the weekend. Another area of low pressure is forecast to swing
into the Ohio Valley Friday through Saturday. Moisture does not look
all that impressive at this time, but rain chances will increase
Friday afternoon and continue into Saturday with the cold frontal
passage.
&&
.Aviation (00Z TAF Issuance)...
Clipper centered over Nashville at 22Z will be in North Carolina by
midnight and will take the light snow with it. Light snow should be
ending at SDF in the first hour of the TAF and by 03 or 04Z at LEX,
with BWG remaining unaffected.
Ceilings will continue to be tricky overnight, with clouds
continuing to stream into the northern TAF sites especially. There
are a few MVFR ceilings upstream in Illinois but the great majority
of the CIGs are VFR so will go with that. Models do suggest that
lower CIGs will be possible, though, so will keep an eye on it.
High pressure will quickly move in behind the departing clipper this
evening and will remain overhead through Sunday morning. As a
result we could see some spotty fog again at BWG in the morning,
though will keep it MVFR for now.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 6 AM EST SUNDAY FOR INZ090>092.
KY...WINTER WEATHER ADVISORY UNTIL 6 AM EST SUNDAY FOR
KYZ025-028>031-
034-038>041-045>049-054>057-066-067.
$$
Mesoscale........13
Short Term.......AL
Long Term........MJP
Aviation.........13
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
120 AM EST SUN JAN 15 2012
.SYNOPSIS...
GREAT LAKES LOW PRESSURE WILL PROVIDE FLURRIES UNTIL IT GIVES WAY
TO TENNESSEE HIGH PRESSURE LATER TODAY TO PROVIDE DRY CONDITIONS
INTO MONDAY MORNING. CANADIAN ROCKIES LOW PRESSURE WILL FIRST BRING
A WARM UP WITH RAIN SHOWERS LATE MONDAY AND TUESDAY, BUT THEN
DELIVER A COOL DOWN WITH SNOW SHOWERS TUESDAY NIGHT INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
PER BLEND OF RECENT RADAR DATA AND HRRR MODEL OUTPUT, CONTINUE TO
FORESEE A SNOW BAND MOVING SOUTH FROM CLEVELAND PROVIDING A CHANCE
OF SNOW SHOWERS FOR LOCATIONS NORTH OF I-70 UNTIL THE BAND
DISSIPATES TOWARD DAYBREAK. MORNING LOWS WILL BE ABOUT 10 DEGREES
COLDER THAN NORMAL.
RECENT SREF MODEL OUTPUT THEN SHOWS HIGH PRESSURE, COMING EAST
FROM TENNESSEE, TO PROVIDE SUFFICIENT SUBSIDENCE AFTER DAYBREAK TO
END ANY REMAINING FLURRIES AND TO CLEAR AWAY MOST CLOUDS BY
MIDDAY.
DESPITE AFTERNOON SUNSHINE, HAVE FORECASTED AFTERNOON HIGH
TEMPERATURES, BASED ON BLEND OF RECENT GFS AND NAM MOS, TO BE NO
WARMER THAN SATURDAY AND SOME 10 DEGREES COLDER THAN NORMAL.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM MONDAY/...
BLEND OF RECENT SREF MODEL OUTPUT CONTINUES TO SHOW HIGH PRESSURE
MAINTAINING DRY CONDITIONS TONIGHT AND MONDAY MORNING. A LOW
PRESSURE SYSTEM, COMING EAST FROM ALBERTA, WILL PUSH A WARM FRONT
THROUGH THE UPPER OHIO VALLEY MONDAY NIGHT.
SO AFTER A COLD MORNING, WITH LOW TEMPERATURES ABOUT 5 DEGREES
COLDER THAN NORMAL, AFTERNOON HIGHS WILL REBOUND TO VALUES
SLIGHTLY WARMER THAN NORMAL. MORE IMPORTANTLY, THE WARM UP TO
TEMPERATURES WARMER THAN FREEZING ENSURES THE INITIAL
PRECIPITATION MONDAY AFTERNOON WILL BE RAIN SHOWERS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
DESPITE MODEL DIFFERENCES, CONSENSUS YIELDS COLD FRONTAL PASSAGE
WILL BE TUESDAY NIGHT. HENCE EXPECT MILD TEMPERATURES AND RAIN
SHOWERS MONDAY NIGHT AND DAYTIME TUESDAY, FOLLOWED BY A SHARP COOL
DOWN AND CHANGE TO SNOW SHOWERS TUESDAY NIGHT. POST SYSTEM
NORTHWEST FLOW MAY TAP ENOUGH GREAT LAKES MOISTURE FOR SNOW
SHOWERS TO LINGER INTO WEDNESDAY.
THE UPPER LEVEL JETSTREAM WILL REMAIN STRONG AND FAIRLY ZONAL INTO
THE WEEKEND, WHICH WILL PROMOTE FAST SYSTEM MOVEMENT. HENCE
LOW PRESSURE ZIPPING THROUGH THE GREAT LAKES TO PROVIDE A CHANCE
OF SNOW SHOWERS AGAIN THURSDAY AND A CHANCE OF RAIN AND SNOW
SHOWERS LATE FRIDAY.
KEPT TEMPERATURES CLOSE TO HPC GUIDANCE WITH TEMPERATURES ABOUT 5
DEGREES COLDER THAN NORMAL WEDNESDAY...MODERATING TO 5 DEGREES
WARMER THAN NORMAL FRIDAY AND PERHAPS TO 10 DEGREES WARMER THAN
NORMAL SATURDAY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
PER RECENT SURFACE AND SATELLITE DATA, EXPECT VFR TO BE PREVALENT
THIS PERIOD. THE ONLY CAVEAT WILL BE THE INFLUENCE OF A DYING SNOW
BAND MOVING SOUTH FROM NORTHEAST OHIO, WHICH MAY PROVIDE A SHORT
PERIOD OF MVFR TIL ABOUT 10Z.
NAM MODEL PROFILES SHOW STRATOCUMULUS DISSIPATING THIS AFTERNOON
DUE TO HIGH PRESSURE SUBSIDENCE.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY...
VFR INTO MIDDAY MONDAY. THEN RESTRICTIONS DEVELOPING DUE TO WARM
FRONTAL SHOWERS LATE MONDAY INTO TUESDAY, AND COLD FRONTAL SNOW
SHOWERS TUESDAY NIGHT INTO WEDNESDAY. THERE CAN AGAIN BE
RESTRICTIONS THURSDAY DUE TO COLD FRONTAL SNOW SHOWERS.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1255 AM EST SUN JAN 15 2012
.SYNOPSIS...
A STRONG UPPER LEVEL DISTURBANCE WILL EXIT OFF THE CAROLINA COAST
THIS MORNING. HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE WEST
TODAY THROUGH MONDAY... BEFORE MOVING OFFSHORE TUESDAY... AHEAD OF
AN APPROACHING COLD FRONT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 909 PM SATURDAY...
PROBLEM OF THE NIGHT WILL BE THE TRACK OF THE MID-UPPER VORTICITY
MAXIMUM FROM SW VA ACROSS NORTHERN/NE NORTH CAROLINA... AND THE
CHANCE OF LIGHT SNOW/FLURRIES ALONG AND NORTH OF THE TRACK.
THE LATEST WV SATELLITE DATA INDICATED THAT THE MID-UPPER LEVEL
VORTICITY MAXIMUM WAS TRACKING ESE ALONG THE WVA/VA BORDER INTO SW
VA. THE RADAR REFLECTIVITY HAS BEEN INCREASING IN COVERAGE AND IN
INTENSITY IN THE PAST FEW HOURS... MAINLY NORTH OF A LINE FROM BOONE
TO KING TO WENTWORTH. LIGHT SNOW HAS BEEN REPORTED ALONG THE BLUE
RIDGE WITH SOME LIGHT ACCUMULATIONS BEGINNING. VISIBILITIES FROM
WYTHEVILLE TO HILLSVILLE/GALAX ARE BETWEEN 3/4 AND 1 MILE WITH SNOW.
THE SUBCLOUD LAYER APPEARS TO HAVE MOISTENED UP QUICKLY AT
ELEVATIONS OF 3K FEET AND ABOVE... ALONG AND NORTH OF THE TRACK OF
THE VORT MAX. HOWEVER... OFF THE BLUE RIDGE... THE SUBCLOUD LAYER
HAS BEEN SLOWER TO MOISTEN UP. NO SNOW HAS BEEN OBSERVED IN THE
TRIAD AS OF 900 PM. IN FACT... THE REFLECTIVITY RETURNS HAVE BEEN
ONLY 5-10DBZ OVER THE WINSTON-SALEM AREA... AND THE SUBCLOUD LAYER
WAS STILL TOO DRY (20 DEGREE F) TEMPERATURE/DEW POINT TEMPERATURE
DEPRESSION AT WINSTON-SALEM AND GREENSBORO.
EXTRAPOLATION OF THE VORTICITY MAXIMUM ESE PER THE LATEST OBSERVED
DATA AND RUC SUGGESTS THAT THE FAVORED AREAS FOR SOME FLURRIES WILL
BE THE NORTHERN PIEDMONT AND NORTHERN COASTAL PLAIN. THE P-TYPE
WOULD BE SNOW SUPPORTED BY THE CURRENT BELOW FREEZING TEMPERATURE
PROFILE AT GSO... WITH THE EXCEPTION OF THE BOUNDARY LAYER... WHERE
CURRENT READINGS WERE IN THE MID 30S... AND DEW POINTS IN THE UPPER
TEENS AND LOWER 20S. PARTIALS INDICATE SNOW AS WELL ACROSS THE
NORTHERN ZONES. THE 00Z/15 JANUARY PARTIALS CAME IN AT 1503M/1299M
ON THE GSO RAOB. CHECKING PAST EVENT CASES... THERE WERE NO
MEASURABLE SNOW EVENTS AT GSO WITH THESE OBSERVED PARTIALS. THIS IS
SIMPLY BECAUSE THE OBSERVED MID LEVELS ARE VERY COLD... AND DRY...
WHICH IS COMMON WITH THESE NW FLOW SYSTEMS... WHEN THE VORT TRACKS
OVERHEAD.
WE WILL KEEP A CHANCE SNOW FLURRIES ACROSS THE NORTH (MAINLY NORTH
OF I-40 TO RALEIGH... THEN NORTH OF US-64 FROM RALEIGH TO WILSON).
THIS WILL BE ALONG AND NORTH OF THE EXPECTED TRACK OF THE VORT MAX.
STILL... THERE IS NOT EXPECTED TO BE ANY ACCUMULATION AS THE SNOW
WOULD BE TOO LIGHT.
SKIES WILL CLEAR LATER TONIGHT... IT WILL BE COLD AGAIN WITH LOWS IN
THE 20S.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 305 PM SATURDAY...
SUNDAY AND SUNDAY NIGHT: A TRAILING DISTURBANCE EMBEDDED WITHIN THE
ELONGATED VORTICITY AXIS BEARING THE LEAD CLIPPER WAVE...WILL PIVOT
THROUGH THE DEPARTING BASE OF THE L/W TROUGH EARLY SUN...FOLLOWED BY
SIGNIFICANT (150M/12HR) MID LEVEL HEIGHT RISES AND THE ARRIVAL OF
STRONG (1035 MB) SURFACE HIGH PRESSURE THROUGH THE REMAINDER OF THE
WEEKEND. THIS SHOULD YIELD SKIES BECOMING SUNNY SUNDAY...WITH CLEAR
SKIES LIKELY TO CONTINUE UNTIL CIRRUS ASSOCIATED WITH A SW US UPPER
JET SPREAD INTO OUR REGION LATE SUN NIGHT. THE HIGH CLOUDS ARE
EXPECTED TO REMAIN THIN ENOUGH AND BE DELAYED SUCH THAT RADIATIONAL
COOLING CONDITIONS WILL BE EXCELLENT AND LEAD TO LOWS IN THE 21 TO
26 DEGREE RANGE. HIGHS GENERALLY 43 TO 50 DEGREES.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 255 PM...
RIDGING SURFACE AND ALOFT MONDAY MORNING. INCREASING MOISTURE IN
WEST SOUTHWEST FLOW AHEAD OF AN APPROACHING SHORT WAVE BUT WEATHER
LIMITED TO CLOUDS THROUGH MONDAY NIGHT. 850 MILLIBAR FLOW INCREASES
TO FIFTY KNOTS OR MORE BY SUNRISE TUESDAY BUT IS RELATIVELY UNIFORM
AND PERHAPS SPEED DIVERGENT. LOW LEVELS ARE STABLE AND THE PARENT
LOW TO THE TROUGH WELL NORTH IN THE EASTERN GREAT LAKES BY SUNSET
TUESDAY. THUS THIS COULD BE A SITUATION OF A VERY HIGH CHANCE FOR
VERY LITTLE RAIN TUESDAY. FORTY PERCENT CHANCE BY TUESDAY AFTERNOON
BUT THIS MAY NEED TO BE DOUBLED... BUT AGAIN FOR VERY LOW AMOUNTS.
THE SURFACE TROUGH FORECAST TO BE OFFSHORE BY SUNRISE WEDNESDAY...
AND RAIN CHANCES WILL DRY UP FROM WEST TO EAST TUESDAY NIGHT... WITH
THE REMAINDER OF THE FORECAST PERIOD DRY.
BEHIND THE FRONT SURFACE HIGH PRESSURE SETTLE OVER NORTH CAROLINA
THURSDAY MORNING... AND IS CENTERED OFFSHORE BY EVENING... NOSING
BACK INTO THE SOUTHEAST STATES. THERE IS ENOUGH AGREEMENT IN AN
UPPER LEVEL WAVE REACHING THE MOUNTAINS SATURDAY TO INTRODUCE A
CHANCE FOR RAIN.
TUESDAY IS EXPECTED TO BE BREEZY WITH SOME GUSTS TO 30 MPH.
AFTERNOON TEMPERATURES NEAR NORMAL MONDAY AT 50 TO 55... WITH RISING
TO NEAR 60 NORTHWEST TO NEAR 67 SOUTHEAST TUESDAY. HIGH TEMPERATURES
MOSTLY 45 TO 50 BEHIND THE FRONT WEDNESDAY AND THURSDAY... RISING
INTO THE FIFTIES FRIDAY... AND LOW TO MID 60S SATURDAY.
LOW TEMPERATURES AROUND 40 MONDAY NIGHT... 35 TO 45 TUESDAY NIGHT.
LOW TEMPERATURES IN THE MID 20S WEDNESDAY NIGHT... RISING INTO THE
40S FRIDAY NIGHT.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 1255 AM SUNDAY...
VFR CONDITIONS WILL HOLD THROUGH TODAY AND TONIGHT. A STRONG UPPER
LEVEL DISTURBANCE AND TROUGH AND ACCOMPANIED SURFACE LOW THAT ARE
NOW MOVING OVER THE AREA WILL MOVE OFF THE COAST BY MID MORNING...
ALLOWING SURFACE HIGH PRESSURE TO BUILD OVER THE REGION FROM THE
WEST... AND CLEARING OUT THE CURRENT VFR CIGS OVER MUCH OF CENTRAL
NC. FEW TO NO CLOUDS ARE EXPECTED THIS AFTERNOON AND EVENING.
SURFACE WINDS WILL BE FAIRLY LIGHT MAINLY FROM THE NW AND N.
LOOKING BEYOND 06Z TONIGHT: MID LEVEL CLOUDS WILL OVERSPREAD THE
AREA BEGINNING MONDAY MORNING WITH VFR CIGS LIKELY BY NOON. AS THE
SURFACE HIGH MOVES TO OUR EAST... DEEP SOUTHWEST FLOW WILL BRING A
GOOD CHANCE OF IFR/LIFR CONDITIONS LATE MONDAY NIGHT THROUGH TUESDAY
MORNING. THE RISK OF MVFR OR IFR CIGS WILL HOLD THROUGH TUESDAY AND
TUESDAY NIGHT AHEAD OF AN APPROACHING COLD FRONT. VFR CONDITIONS ARE
EXPECTED TO RETURN WEDNESDAY. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...BADGETT/MWS
SHORT TERM...MWS
LONG TERM...RLH
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1202 AM EST SUN JAN 15 2012
.SYNOPSIS...
A FEW CLOUDS WILL ACCOMPANY A WEAK SYSTEM OVERNIGHT. HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTH OVER THE NEXT
SEVERAL DAYS. RAIN CHANCES RETURN WITH A COLD FRONT LATE TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM SUNDAY...LATEST RUC AND NAM MODELS INDICATE A THINNING
SWATH OF MOISTURE BETWEEN 850 MB AND 500 MB ASSOCIATED WITH THE
CHANNELED UPPER LEVEL DISTURBANCE. MID LEVEL SCATTERED CLOUDS
MAY AFFECT THE NORTHERNMOST PORTIONS OF THE ILM CWA. JUST TOO DRY
FOR PCPN TO REACH THE GROUND BEFORE SUBLIMATING. THERE WILL BE A SFC
REFLECTION OF THE SFC LOW MOVING FROM THE TN-NC BORDER TO OFF CAPE
LOOKOUT BY DAYBREAK. WINDS WILL SLOWLY PICK UP OVERNIGHT... WITH SW
AHEAD OF THE LOW VEERING TO W TO NW AFTER ITS PASSAGE. TEMPERATURES
REACHED A MINIMUM EARLIER THIS EVENING AND HAVE ACTUALLY RISEN
SEVERAL DEGREES DUE TO BETTER MIXING WITH STRONGER LOW-LEVEL WINDS.
TEMPERATURES WILL BEGIN TO FALL AGAIN LATE WITH INCREASING COLD
ADVECTION.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...A LARGELY MOISTURE-STARVED CLIPPER WILL BE
CROSSING THE REGION AT THE START OF THE PERIOD. A FEW RADAR ECHOES
MAY BE OBSERVED BUT ANY PRECIP WILL BE VERY HARD PRESSED TO REACH
THE GROUND. OTHERWISE VERY QUIET WEATHER THROUGH THE PERIOD. IN FACT
FORECAST SOUNDINGS SHOW THAT ONLY CLOUDS IN THE SHORT TERM WILL BE A
GRADUAL INCREASE OF CIRRUS AND EVENTUALLY CIRROSTRATUS LATE MONDAY
AND MONDAY NIGHT. AN EXITING SHORTWAVE AND SURFACE HIGH PRESSURE
BUILDING IN FROM THE NORTH WILL BRING COME CAA ON SUNDAY KEEPING
TEMPS JUST A FEW DEGREES BELOW CLIMO...GENERALLY IN THE LOW 50S.
850MB TEMPS REMAIN IN THE -2 TO -4C RANGE BUT LIGHT WINDS SHOW THAT
MIXING WILL PROBABLY ONLY DEEPEN TO ABOUT 900MB. THE SURFACE RIDGE
WILL MAKE ITS WAS OFF THE NC/VA COASTLINE LATE MONDAY ALLOWING FOR A
TURN TO THE SOUTH IN THE SURFACE AND LOWER LEVELS. OVERALL WINDS
REMAIN QUITE LIGHT HOWEVER SO SHALLOW MIXING WILL TEMPER ANY WARMUP
DESPITE THE GOOD WARMING SEEN AT 850MB. MID LEVEL FLOW REMAINS LOW
IN AMPLITUDE...NEARLY ZONAL. TWIN UPPER LEVEL JET MAXES DEVELOPING
OVER THE MIDDLE OF THE NATION WILL LEAD TO THE AFOREMENTIONED
INCREASE OF CIRRUS LEVEL MOISTURE LOCALLY ON MONDAY.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 230 PM SATURDAY...MODELS BRING FRONT AND ASSOCIATED PCPN OFF
THE COAST DURING THE EARLY PART OF THE LONG TERM FORECAST WITH HIGH
PRESSURE BUILDING INTO THE EASTERN PORTION OF THE COUNTRY WITH
COOLER TEMPS FOR THURSDAY WITH A NNE FLOW ACROSS THE REGION. HIGH
SLIDES OFF THE COAST FRIDAY WITH NICE RETURN FLOW SETTING UP BEHIND
IT WITH TEMPS MODERATING INTO THE LOWER 60S FRIDAY AND MID 60S ON
SATURDAY A GOOD 5-10 DEGREES ABOVE NORMAL. H5 PATTERN REMAINS FLAT
AND PROGRESSIVE WITH NEXT UP STREAM SHORT WAVE MOVING OUT OF THE
CENTRAL/SOUTHERN PLAINS INTO THE LOWER OHIO/TENNESSEE VALLY ON
SATURDAY. THE ECMWF IS DEEPER AND MORE AGGRESSIVE WITH THIS FEATURE
DEVELOPING A SURFACE LOW IN THE OHIO VALLEY WHILE THE GFE HAS A MORE
OPEN WAVE DEVELOPING. BOTH MODELS SHOW MOISTURE STREAMING UP FROM
THE GULF AHEAD OF THIS FEATURE WITH THE ECMWF BRINGING SOME PCPN
INTO THE CWA DURING THE DAY SATURDAY. H8 MOISTURE TRANSPORT VECTORS
INDICATE BOTH GULF AND ATLANTIC MOISTURE BEING TAP MAXIMIZED BETWEEN
18Z SAT AND 06Z SUNDAY. THE GFE/CMC NHEM 12Z MODEL RUNS ARE NOT AS
AGGRESSIVE HERE AS THE ECMWF AND IS MORE LIMITED WITH THE MOISTURE.
WITH PLENTY OF TIME YET TO ANALYZE THIS NEXT FEATURE WILL LEAN
TOWARDS THE GFE/CMC SOLUTION NOW WITH NEXT SYSTEM MOVING ACROSS THE
AREA ON SATURDAY WITH SOME PCPN.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...HIGH CONFIDENCE FOR VFR CONDITIONS THROUGH THE FORECAST
PERIOD. A WEAK SHORT WAVE AND ASSOCIATED LOW PRESSURE WILL CROSS THE
REGION THROUGH THE OVERNIGHT HOURS. ANY PRECIPITATION SHOULD STAY
NORTH OF THE TERMINALS...WITH ONLY A MID CLOUD CEILING EXPECTED.
AFTER THE VORT MOVES THROUGH...EXPECT A WIND SHIFT TO THE NORTHWEST
BY MID MORNING...AND GUSTY. SOME CU FORMATION IS POSSIBLE BY LATE
MORNING WITH FAIRLY STEEP LOW LAPSE RATES.
EXTENDED OUTLOOK...LOW CONFIDENCE IFR FOG INLAND TERMINALS EARLY
TUESDAY MORNING AND SHOWERS/TEMPO IFR LATE TUESDAY INTO WEDNESDAY.
OTHERWISE VFR.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 1230 AM SUNDAY...NO SIGNIFICANT CHANGES NEEDED FOR THE VERY
EARLY MORNING UPDATE. PREVIOUS DISCUSSION FROM 930 PM FOLLOWS...
A QUICK MOVING CLIPPER LOW AND ASSOCIATED COLD FRONT IS PROGGED TO
MOVE ACROSS THE COASTAL WATERS BY DAYBREAK. POST FRONTAL W TO NW
WINDS WILL INCREASE TO 15 TO 25 KT BY DAYBREAK AND CONTINUE INTO
MIDDAY SUNDAY. SIGNIFICANT SEAS WILL BE RULED BY THE LOCALLY
PRODUCED WIND DRIVEN...3 TO 6 SECOND PERIOD WAVES. AND WITH AN
OFFSHORE TRAJECTORY...A RANGE OF SEAS WILL BE FORECAST. FRYING PAN
SHOALS WILL EXHIBIT WASHING MACHINE TYPE CONDITIONS...
WITH LOCALLY HIGHER WAVES LIKELY.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...NW WINDS WILL INCREASE SOME EARLY SUNDAY WITH
THE OFFSHORE EXIT OF A CLIPPER TYPE OF DISTURBANCE AT BOTH THE
SURFACE AND ALOFT. CAUTIONARY HEADLINES ARE NOT ANTICIPATED EVEN
WITH A LITTLE MIXING AS FORECAST SOUNDINGS SHOW NO HIGHER THAN 20
KNOTS THROUGH MOST OF WHAT SHOULD BE THE BOUNDARY LAYER OVER THE
MARINE ZONES...ESPECIALLY GIVEN THE COOLER SSTS OF THE NEARSHORE
WATERS. SUNDAY AFTERNOON WILL BRING A VEERING AND DECREASING WIND
REGIME AS HIGH PRESSURE BUILDS ACROSS VA AND THE GRADIENT EASES
LOCALLY. THIS SAME HIGH WILL ONLY SLOWLY MIGRATE EASTWARD FOR THE
REMAINDER OF THE SHORT TERM PERIOD ALL WHILE KEEPING A WEAK RIDGE
AXIS INTO THE COASTAL CAROLINAS. AS SUCH THE WINDS WILL REMAIN QUITE
LIGHT...GENERALLY 10KT...LEADING TO A MERE 2 FT WIND WAVE. AN
ADDITIONAL VEER TO A SOUTHERLY DIRECTION IS SLATED FOR MONDAY NIGHT
AS THE HIGH MOVES EVEN FURTHER OUT TO SEA AND A COLD FRONT REACHES
THE OH AND MS RIVER VALLEY REGIONS. AN INCREASE IN SPEED WILL ALSO
RESULT MONDAY NIGHT...GRADUALLY AT FIRST AND THEN WITH MORE VIGOR
AFTER ABOUT 06Z. SEAS COULD BUILD TO 5 FT ALONG THE EASTERN FRINGE
OF SOME OF THE ZONES NECESSITATING SCEC BUT A PEEK INTO THE LONG
TERM WOULD SUGGEST THAT A SMALL CRAFT ADVISORY WILL INSTEAD BE
HOISTED DUE TO FURTHER ANTICIPATED DETERIORATION OF CONDITIONS.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 230 PM SATURDAY...COLD FRONT APPROACHES THE WATERS ON TUESDAY
NIGHT INTO EARLY WEDNESDAY AND OFF THE COAST BY 12Z. TIGHT GRADIENT
WITH WINDS INCREASING FROM THE SW AT 20-25 KTS AHEAD OF FRONT WITH
SEAS BUILDING TO 5-7 FEET RESULTING IN SCA CRITERIA LATE TUESDAY
INTO MID DAY WEDNESDAY. ONCE FRONTS PASSES THE WINDS BACK FROM THE
SW TO WEST AND THEN BECOME MORE NORTHERLY BY 18Z WITH THE SEAS
DIMINISHING TO 3-5 FEET...2-4 FEET NEAR SHORE. WINDS WILL REMAIN
BRISK AT 15-20 KTS AND VEER TO THE NE ON THURSDAY BEFORE SLOWLY
DIMINISHING AS HIGH PRESSURE BUILDS ACROSS THE WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 3 AM TO 1 PM EST SUNDAY FOR
AMZ250-252-254-256.
&&
$$
SYNOPSIS...MBB
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MAC
AVIATION...SHK
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
408 AM EST SUN JAN 15 2012
.SHORT TERM (TODAY AND TONIGHT)...
SOME LIGHT SNOW LINGERS OVER PORTIONS OF SW VA AND THE NE TN
MOUNTAINS EARLY THIS MORNING. BASED ON RADAR AND SATELLITE TRENDS
AND RUC FORECAST SOUNDINGS...THESE SHOULD BE TAPERING OFF SOON. WILL
INCLUDE A MENTION OF FLURRIES IN THESE AREAS FOR THE EARLY
MORNING...BUT WITH ACCUMULATING SNOWFALL ENDING...WILL DROP THE
WINTER WEATHER ADVISORY.
SURFACE HIGH PRESSURE WILL BE DRIFTING ACROSS THE AREA TODAY...WITH
A BUILDING RIDGE ALOFT. CLOUDS IN THE NORTH THIS MORNING WILL
GRADUALLY DECREASE...AND ALL AREAS SHOULD SEE FULL SUN BY THE
AFTERNOON. HIGHS WILL RANGE FROM THE UPPER 40S SOUTH TO MID/UPPER
30S NORTH. NEUTRAL TEMPERATURE ADVECTION DURING THE DAY WILL
TRANSITION TO SLIGHT WARM ADVECTION TONIGHT AS THE HIGH SHIFTS EAST
OF THE MOUNTAINS AND LOW PRESSURE TRACKS ACROSS THE PLAINS. HIGH
CLOUDS WILL ALSO BEGIN TO INCREASE LATE TONIGHT AHEAD OF THIS
SYSTEM.
.LONG TERM (MONDAY THROUGH SATURDAY)...HIGH PRESSURE ACROSS THE AREA
PROVIDING DRY WEATHER FOR MOST OF MONDAY. A FRONT MOVES INTO THE
AREA ON MONDAY NIGHT AND TUESDAY. WILL KEEP THE CHANCE POPS FOR BOTH
MONDAY NIGHT AND TUESDAY. IT SHOULD BE WARM ENOUGH FOR ALL LIQUID
PRECIPITATION ON MONDAY NIGHT. IT SHOULD ALSO BE BREEZY ON MONDAY
AND TUESDAY. THE FRONT IS EXPECTED TO EXIT THE REGION ON TUESDAY
NIGHT. THE PRECIPITATION COULD CHANGE TO LIGHT SNOW AS IT EXITS THE
AREA ON TUESDAY NIGHT. HIGH PRESSURE RETURNS BRINGING DRY WEATHER ON
WEDNESDAY THROUGH FRIDAY. ANOTHER FRONT TRACKING THROUGH THE REGION
ON SATURDAY. WITH STILL UNCERTAINTY ON TIMING...WILL LEAVE THE
CURRENT LOW POPS FOR SATURDAY AS IS.
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 47 28 53 44 58 / 0 0 20 60 60
KNOXVILLE MCGHEE TYSON AIRPORT, TN 42 25 52 42 55 / 10 0 20 60 60
OAK RIDGE, TN 42 25 52 42 55 / 10 0 20 60 60
TRI CITIES AIRPORT, TN 38 21 51 38 52 / 10 0 20 60 60
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS/GH
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1054 PM CST SAT JAN 14 2012
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE AND ADDED MENTION OF
LAKE EFFECT TRENDS OVER LK MICHIGAN TO THE UPDATE SECTION
.UPDATE...HAVE MADE A COUPLE FUTILE ATTEMPS TO ADJUST SKY COVER AND
TEMPS THIS EVENING...BUT UNLESS CLOUDS INCREASE QUICKLY OVER FAR NE
WI...TEMPS WILL LIKELY DROP SEVERAL DEGREES BLO ZERO THERE. WHERE
CLOUDS HAVE ALREADY THICKENED OVER THE SW TWO-THIRDS OF THE CWA...
TEMPS HAVE GENERALLY REMAINED STEADY OR WARMED BACK INTO THE UPPER
SINGLE DIGITS/LOWER TEENS. MAY ALSO NEED TO CONSIDER WARMING
TEMPS MORE LATE TONIGHT... ESPECIALLY OVER C WI...SOME LLVL WAA IS
ANTICIPATED. CURRENT READINGS ARE IN THE UPPER TEENS OVER WSTRN
WI. MAY NEED TO TAKE ONE MORE STAB AT SKY COVER/TEMPS BEFORE
LEAVING AT 11 PM.
MESO-LOW OVER CNTRL LK MICH WAS HELPING TO DEVELOP A PATCH OF
HEAVY SNOW SNOW SHOWERS OVER MID-LAKE LATE THIS EVG...BUT LLVL
WINDS ARE EXPECTED TO EVENTUALLY TURN SW OVERNIGHT...WHICH SHOULD
KEEP IT OFFSHORE FROM DOOR COUNTY. MIDNIGHT SHIFT WILL NEED TO
WATCH CLOSELY THOUGH...AS IT MAY GET PRETTY CLOSE TO SHORE.
KIECKBUSCH
&&
.PREV DISCUSSION...ISSUED AT 551 PM CST SAT JAN 14 2012...
SHORT TERM...TONIGHT AND SUNDAY.
THE SURFACE PRESSURE PATTERN OVER THE REGION WAS CAUSING SOME
ISSUES IN THE SHORT TERM. 20Z ANALYSIS SHOWED WEAK LOW PRESSURE
OVER LAKE MICHIGAN...A WEAK RIDGE OVER WISCONSIN AND A TROUGH
ACROSS MINNESOTA.
CONVERGENCE OVER THE LAKE RESULTED IN A BAND OF LAKE EFFECT SNOW
SHOWERS THAT PUSHED WEST INTO DOOR COUNTY. THE 15Z RUC APPEARED TO
HAVE A DECENT HANDLE ON THE SITUATION AS IT WAS SHOWING QPF IN THE
EASTERN PART OF THE FORECAST AREA INTO THIS EVENING. WENT WITH
SOME POPS IN THE EAST FOR THE EVENING BUT DRY THERE AFTER 06Z.
NOT REALLY SURE WHAT WAS CAUSING THE LIGHT SNOW AND FLURRIES IN
CENTRAL WISCONSIN TODAY DIRECTLY UNDER THE SURFACE RIDGE...POSSIBLY
SOME WEAK SHORT WAVE ENERGY PASSING THROUGH THE STATE. THE
VISIBILITY IN SOME LOCATIONS WENT AS LOW AS 3 MILES WITH SNOW AT
TIMES.
ANOTHER AREA OF LIGHT SNOW...WITH VISIBILITIES BELOW 2 MILES...WAS
ASSOCIATED WITH A WARM FRONT ACROSS MINNESOTA...AND A SHEARED UPPER
LEVEL SHORT WAVE. MODELS HAD THE FRONT DECAYING...THE SHORT WAVE
ENERGY MOVING SOUTHEAST THIS EVENING AND HAD QPF DRYING UP BEFORE
REACHING THE FORECAST AREA. HAVE SOME SLIGHT CHANCE POPS FOR
CENTRAL WISCONSIN DURING THE EVENING...BUT NOTHING AFTER 06Z.
TIME/HEIGHT SECTIONS FROM MODELS HAD QUITE A BIT OF LOW LEVEL
MOISTURE WITH LITTLE LIFT LATE TONIGHT...MAINLY IN THE NORTH. SO
HAVE INCLUDED A SLIGHT CHANCE OF FREEZING DRIZZLE OR FLURRIES
THERE 06Z-12Z SUNDAY.
PLENTY OF CLOUDS TONIGHT...BUT THINK THAT TEMPERATURES SHOULD FALL
INTO THE SINGLE DIGITS IN MOST LOCATIONS. WARMER THAN NORMAL HIGHS
RETURN ON SUNDAY IN STRONG WARM ADVECTION AHEAD OF THE SURFACE
SYSTEM APPROACHING FROM THE WEST. MODELS STILL HAD PLENTY OF
CLOUDS SO DID NOT GO TOO MUCH ABOVE GUIDANCE HIGHS.
EXPECT WINDS TO STEADILY INCREASE DURING THE DAY ON SUNDAY AHEAD
OF THE APPROACHING SYSTEM.
LONG TERM...MONDAY THROUGH NEXT SATURDAY.
NOT MUCH CHANGE TO THE IDEA OF DEVELOPMENT OF HIGH AMPLITUDE
RIDGING OVER THE BERING STRAIT WITH NRN STREAM ENERGY DIGGING SE
THRU ALASKA/WRN CANADA. THIS RESULTS IN DEVELOPING BROAD UPPER
TROF ACROSS SRN CANADA/NRN CONUS. THE MEAN FLOW UNDER THIS TROF TO
BE NEAR ZONAL FROM THE US...BRINGING SEVERAL RELATIVELY WEAK
SYSTEMS ACROSS THE WRN GREAT LAKES.
AT BEGINNING OF PERIOD...LOW PRESSURE MOVES EAST INTO CNTRL
ONTARIO SUNDAY NGT AND DRAGS COLD FRONT INTO CNTRL WI BY 12Z MONDAY. IT
STILL APPEARS THAT GULF MOISTURE WILL NOT HAVE TIME TO REACH THE
FORECAST AREA PRIOR TO THE FRONTAL PASSAGE. FRONT EXISTS REGION BY
EARLY IN THE AFTERNOON...THEN SHORT WAVE TROF APPROACHES FROM THE W.
SNOW SHOULD DEVELOP ALONG TIGHT BAROCLINIC ZONE ACROSS THE AREA BY
EARLY TUESDAY. ALL MODELS IN GENERAL AGREEMENT WITH DEVELOPMENT OF SFC
WAVE ALONG THE FRONT. ACCUMULATIONS SHOULD BE GENERALLY
MINOR...LESS THAN 2 INCHES THRU TUE. SOME LAKE EFFECT LINGERS IN
LAKE SUPERIOR SNOW BELT OF FORECAST AREA INTO TUE NIGHT. MIDWEEK
TEMPS WILL BE BELOW NORM AS ARCTIC AIR BRIEFLY FINDS A HOME.
SMALL CHANCES FOR SNOW SHOWERS ACROSS AREA AS WEAK RIPPLES IN WNW
UPPER FLOW CONTINUE TO MOVE ALONG BAROCLINIC ZONE. BOTH THE 14/12Z
GFS AND ECMWF TARGET FRIDAY AS THE BEST SNOW CHANCE IN THE SECOND
HALF OF THE WEEK WITH SHORT WAVE TROF MOVING ACROSS MIDWEST AND
SURFACE LOW MOVING ACROSS S ILLINOIS.
&&
.AVIATION...MVFR CIGS WERE MOVG BACK INTO CENTRAL WI LATE THIS
EVENING...AND SHOULD PROGRESS EAST ACROSS THE REGION DURING THE
OVERNIGHT HOURS...REACHING THE LKSHR BY DAYBREAK. ASIDE FROM A
FEW FLURRIES...LITTLE OR NO PCPN IS EXPECTED. VFR CONDITIONS
SHOULD RETURN TO NC/C WI BY MID MORNING...AND NE/EC WI BY AROUND
MIDDAY. HAVE ADDED SOME LLWS FOR LATE SUNDAY AFTERNOON AND
EVENING...AS SSW WINDS INCREASE TO AROUND 40 KTS 1500-2000 FT AGL.
SFC WIND GUSTS WILL ALSO BE ON THE INCREASE DURING THE LATE
AFTERNOON/EVG. SOME LOW CLOUDS MAY REDEVELOP AHEAD OF AN APPROACHING
COLD FRONT SUNDAY EVG...AND THERE IS A SMALL CHC OF SOME FREEZING
DRIZZLE. CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE A MENTION OF THE
FREEZING DRIZZLE...BUT DID INCLUDE EVENING TEMPO GROUPS FOR SOME
MVFR CIGS.
KIECKBUSCH
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
554 AM CST SUN JAN 15 2012
...UPDATE TO AVIATION...
.AVIATION...
VFR CONDITIONS EXPECTED WITH LLWS LIKELY THE MAIN ISSUE FOR MOST
OF THE FORECAST PERIOD. WINDS PROGGED TO START TO RELAX IN THE
AFTERNOON INTO THE OVERNIGHT HOURS AND REMAIN SOUTHERLY. FRONT
APPROACHES FROM THE NORTH OUTSIDE THE TAF PERIOD. 67
&&
.FIRE WEATHER...
EXPECT SOUTHERLY WINDS TODAY TO INCREASE TO 15 TO 25 MPH WITH
GUSTS OF UP TO 35 MPH. EXPECT THE STRONGEST WINDS TO BE ACROSS
AREAS EAST OF A MARYSVILLE TO COUNCIL GROVE LINE...HOWEVER EVEN
AREAS WEST OF THIS LINE COULD SEE WINDS OF 15 TO 25 MPH TODAY.
MIXING WILL BE FAIRLY SHALLOW ON SUNDAY...HOWEVER THE SOUTHERLY
WINDS WILL ADVECT AIR FROM ACROSS SOUTHERN MISSOURI...EASTERN
OKLAHOMA...AND WESTERN ARKANSAS NORTHWARD INTO EASTERN KANSAS.
CURRENTLY THE DEWPOINTS OF THIS AIRMASS ARE IN THE LOWER TO MID 20
DEGREE RANGE...SO FEEL THAT DEWPOINTS ACROSS THE AREA WILL NOT
REACH MUCH HIGHER THAN 25 DEGREES...WHICH IN COMBINATION WITH THE
LOWER 60 DEGREE AIR WILL YIELD MIN RH VALUES IN THE LOWER TO MID
20 PERCENT RANGE FOR THIS AFTERNOON. AS A RESULT OF THESE
CONDITIONS VERY HIGH FIRE DANGER WILL EXIST ACROSS PARTS OF THE
AREA FOR TODAY. CONDITIONS WILL NEED TO BE MONITORED THROUGHOUT
THE DAY IN CASE THE AIR DRIES OUT MORE THAN EXPECTED.
JL
&&
.PREV DISCUSSION...
/ISSUED 407 AM CST SUN JAN 15 2012/
SHORT RANGE (TODAY AND MONDAY)...
09Z WATER VAPOR IMAGERY AND RUC ANALYSIS INDICATES TWO UPPER TROUGHS
OVER THE CONUS. ONE IS LOCATED ROUGHLY OVER THE NEW ENGLAND
STATES..WITH THE OTHER JUST COMING ON SHORE OVER THE PACIFIC
NORTHWEST. BETWEEN THESE TWO TROUGHS IS A FLEETING UPPER RIDGE WHICH
WILL TRANSIT ACROSS THE AREA THROUGH THE DAY TODAY. STRONG SOUTHERLY
WINDS WILL PICK UP IN INTENSITY TODAY IN RESPONSE TO A NORTH-SOUTH
ELONGATED SURFACE TROUGH WHICH WILL MOVE OFF THE NORTHERN ROCKIES
TODAY. EXPECT THE SOUTHERLY WINDS TO REACH THE 20 TO 30 MPH
RANGE...WITH GUSTS OF UP TO 35 MPH. WARM AIR ADVECTION ASSOCIATED
WITH THE SOUTHERLY FLOW IN CONJUNCTION WITH THE QUICKLY MOVING
RIDGE WILL BRING A CLEAR AND UNSEASONABLY WARM DAY TO NORTHEAST
KANSAS. EXPECT ONLY SHALLOW MIXING TODAY WITH A STRONG INVERSION
EXPECTED TO SET UP NEAR THE 925 MB LEVEL...BUT DRY AIR JUST OFF
THE SURFACE WILL BE ALLOWED TO MIX TO THE SURFACE CAUSING DRY
CONDITIONS TODAY...LENDING TO AN ENHANCED FIRE DANGER TODAY. WILL
NEED TO CONTINUE TO MONITOR THE CONDITIONS AS THE DAY WEARS ON AND
MAKE ADJUSTMENTS TO THE FORECAST AS NECESSARY.
THE WARM UP WILL NOT LAST LONG AS A STRONG COLD FRONT WILL MOVE INTO
THE AREA ON MONDAY EVENING. PORTIONS OF EAST CENTRAL KANSAS WILL
LIKELY SEE ANOTHER DAY OF UPPER 50 TO LOWER 60 DEGREE TEMPS ON
MONDAY AS THOSE AREAS WILL REMAIN AHEAD OF THE COLD FRONT. AREAS
BEHIND THE FRONT...NAMELY AREAS NORTH AND WEST OF THE KANSAS
TURNPIKE...WILL LIKELY ONLY SEE HIGHS IN THE LOWER TO MID 40S ON
MONDAY. ON MONDAY NIGHT THE PARENT MID TO UPPER LEVEL TROUGH WILL
PASS THROUGH THE NORTHERN PLAINS...CAUSING THE MOST SIGNIFICANT LIFT
TO REMAIN NORTH OF THE KS/NE BORDER. WITH THE MARGINAL LIFT AND DRY
AIR OVER NORTHEAST KANSAS DO NOT EXPECT VERY MUCH PRECIPITATION FROM
THIS SYSTEM. THE AREA WITH THE BEST CHANCE FOR ANY PRECIP ON MONDAY
NIGHT WILL BE EXTREME NORTH CENTRAL AND NORTHEASTERN KANSAS...MAINLY
ALONG HIGHWAY 36...BUT EVEN THESE AREAS ARE NOT EXPECTED TO SEE MUCH
MORE THAN SOME FLURRIES OR OCCASIONAL LIGHT SNOW WITH LITTLE TO NO
ACCUMULATION EXPECTED.
MID RANGE AND EXTENDED FORECAST (TUESDAY THROUGH SATURDAY)...
BY TUESDAY STRONG NORTHERLY WINDS OF 20 TO 30 MPH WILL USHER IN
ANOTHER ARCTIC AIR MASS INTO THE THE CENTRAL PLAINS. WITH THE COLD
AIR BECOMING FIRMLY ENTRENCHED OVER THE AREA EXPECT TEMPS ON TUESDAY
TO MAX OUT IN THE UPPER 20S TO LOWER 30S ACROSS ALL OF NORTHEAST
KANSAS. WEDNESDAY NIGHT WILL LIKELY BE THE COLDEST PERIOD OF THIS
FORECAST AS THE SURFACE RIDGE BECOMES CENTERED OVER THE AREAS
CAUSING THE OVERNIGHT LOWS TO FALL TO THE LOWER TO MID TEENS. BY WED
ANOTHER BRIEF WARM UP IS EXPECTED AS SOUTH-SOUTHWEST WINDS BRING WARM
AIR BACK INTO THE AREA. EXPECT ANOTHER MILD DAY ON WED WITH TEMPS
MAXING OUT IN THE MID TO UPPER 40S. EXPECT THE GRADUAL WARM UP TO
CONTINUE THROUGH THE END OF THE WEEK BRINGING MILD CONDITIONS TO THE
AREA.
JL
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
412 AM MST SUN JAN 15 2012
.SYNOPSIS...
LATEST SATELLITE IMAGERY AND RUC UPPER AIR ANALYSIS SHOWED
NORTHWESTERLY UPPER LEVEL FLOW TURNING TO THE WEST AS AN UPPER
LEVEL RIDGE MOVES OVER THE CENTRAL PLAINS. AT THE SURFACE A TROUGH
OF LOW PRESSURE WAS PROGRESSING EAST ACROSS THE TRI-STATE
AREA...CAUSING THE SOUTHWEST WINDS TO SHIFT TO THE WEST BEHIND IT.
JTL
&&
.SHORT TERM (TODAY-TUESDAY)...
257 AM MST SUN JAN 15 2012
MAIN FOCUS WILL BE SNOWFALL CHANCES WITH THE COLD FRONT ON MONDAY
AND MONDAY NIGHT.
TODAY AND TONIGHT...AN UPPER LEVEL RIDGE WILL BUILD INTO THE
TRI-STATE AREA TODAY. TONIGHT A COLD FRONT WILL MOVE THROUGH DURING
THE OVERNIGHT HOURS AHEAD OF AN UPPER LEVEL TROUGH THAT WILL MOVE
THROUGH MONDAY NIGHT. A SHALLOW LAYER OF MOISTURE WILL DEVELOP AS
THE COOLER AIR MOVES INTO THE AREA...CAUSING SOME CLOUDS TO
DEVELOP.
MONDAY...MOISTURE AND LIFT BEGIN TO MOVE INTO THE AREA FROM THE
NORTHWEST AHEAD OF THE UPPER LEVEL TROUGH DURING THE LATE
AFTERNOON...ALLOWING FOR SOME SLIGHT CHANCES FOR SNOWFALL FOR
MAINLY YUMA COUNTY.
MONDAY NIGHT...MOISTURE AND LIFT WILL MOVE OVER MOST OF THE AREA.
MODELS CONTINUE TO INDICATE THE BEST LIFT WILL GENERALLY BE AHEAD OF
THE BULK OF THE MOISTURE...WITH THE BEST COLLOCATION OF LIFT AND
MOISTURE DURING THE EVENING HOURS MAINLY NORTH OF HIGHWAY 24.
INCLUDED PRECIP. CHANCES FOR THE ENTIRE AREA DUE TO SOME
UNCERTAINTY IN THE TIMING AND STRENGTH OF THE LIFT AS IT MOVES
THROUGH. OVERNIGHT THE SNOWFALL LOOKS TO COME TO AN END FROM WEST
TO EAST AS THE UPPER LEVEL TROUGH MOVES THROUGH THE AREA. THE HILL
CITY AND NORTON AREAS MAY SEE SOME SNOW DURING THE OVERNIGHT HOURS...WITH
THE REST OF THE AREA LIKELY TO SEE SOME FLURRIES AS THE UPPER
LEVEL TROUGH MOVES EAST OUT OF THE AREA. WITH THE SREF CON TINING
TO PLACE THE BETTER CHANCES OVER NORTHERN NEBRASKA AND THE
MOISTURE MOVING IN BEHIND THE MAIN AREA OF LIFT...WILL CONTINUE
WITH LIGHT TOTAL SNOWFALL ACCUMULATIONS OF AN INCH OR LESS. MODELS
ALSO UNSURE OF THE STRENGTH OF THE WINDS AS THE SURFACE LOW MOVES
THROUGH DURING THE NIGHT. TRENDED THE WINDS TOWARD THE STRONGER
SOLUTIONS AS NAM AND GFS MSL PRESSURE PLOTS SHOW A STRONG GRADIENT
OVER THE AREA AS THE LOW MOVES THROUGH.
TUESDAY DRIER AIR AND A SURFACE HIGH PRESSURE MOVE INTO THE AREA.
HIGH TEMPERATURES FOR THE PERIOD WILL BE THE WARMEST TODAY. EASTERN
COLORADO WILL HAVE NEAR RECORD TEMPERATURES TODAY. THERE ARE SOME
CLOUDS MOVING IN FROM THE NORTHWEST...SO THESE WILL HAVE SOME AFFECT
ON HOW WARM TEMPERATURES WILL BE FOR THE WESTERN AREAS. MONDAY
TEMPERATURES WILL BE NEAR TO BELOW NORMAL AS COOLER AIR COMES IN
FROM THE NORTHEAST. THE CHEYENNE WELLS TO LEOTI AREA MAY HAVE
TEMPERATURES NEAR 50 IF THE FRONT DOES NOT MOVE THROUGH UNTIL LATE
AFTERNOON. TUESDAY TEMPERATURES WILL BE BELOW NORMAL.
LOW TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL TONIGHT AS THE COOLER
AIR BEGINS TO MOVE IN. MONDAY NIGHT LOWS WILL BE IN THE LOWER TO
MID TEENS AS BRISK NORTH WINDS CONTINUE TO BRING COOLER AIR INTO THE
AREA. TUESDAY NIGHT TEMPERATURES WILL BE NEAR NORMAL DESPITE THE
MOSTLY CLEAR SKIES AND DRY AIR.
JTL
.LONG TERM (WEDNESDAY-SATURDAY)...
257 AM MST SUN JAN 15 2012
NORTHWEST FLOW WILL PREVAIL ACROSS THE CENTRAL PLAINS THROUGH
FRIDAY. UPPER FLOW TRANSITIONS TO SOUTHWEST FLOW SATURDAY AS A
TROUGH DIGS INTO THE PACIFIC NORTHWEST. A SURFACE TROUGH WILL
PERSIST OVER EASTERN COLORADO THROUGH THURSDAY NIGHT AND THEN
SHIFT EAST FRIDAY. ANOTHER TROUGH WILL MOVE INTO EASTERN COLORADO
SATURDAY. DISTURBANCES COME THROUGH THE FLOW BUT LACK OF MOISTURE
WILL KEEP POPS NIL. MAX TEMPERATURES WILL RANGE FROM THE MID 40S
WEDNESDAY TO THE MID/UPPER 50S SATURDAY. MIN TEMPERATURES WILL
RANGE FROM THE MID/UPPER 20S WEDNESDAY NIGHT TO LOWER 30S SATURDAY
NIGHT.
FS
&&
.AVIATION...
412 AM MST SUN JAN 15 2012
FOR THE 12Z TAFS...VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24
HOURS AT KGLD AND KMCK. SOME HIGH CLOUDS WILL PASS OVER THE
TERMINALS OCCASIONALLY AND WINDS WILL GENERALLY BE LIGHT FROM THE
SOUTHWEST TURNING TO THE NORTHEAST BEHIND THE FRONT AT KMCK EARLY
SUNDAY MORNING.
FS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
316 AM MST SUN JAN 15 2012
.SYNOPSIS...
LATEST SATELLITE IMAGERY AND RUC UPPER AIR ANALYSIS SHOWED
NORTHWESTERLY UPPER LEVEL FLOW TURNING TO THE WEST AS AN UPPER
LEVEL RIDGE MOVES OVER THE CENTRAL PLAINS. AT THE SURFACE A TROUGH
OF LOW PRESSURE WAS PROGRESSING EAST ACROSS THE TRI-STATE
AREA...CAUSING THE SOUTHWEST WINDS TO SHIFT TO THE WEST BEHIND IT.
JTL
&&
.SHORT TERM (TODAY-TUESDAY)...
257 AM MST SUN JAN 15 2012
MAIN FOCUS WILL BE SNOWFALL CHANCES WITH THE COLD FRONT ON MONDAY
AND MONDAY NIGHT.
TODAY AND TONIGHT...AN UPPER LEVEL RIDGE WILL BUILD INTO THE
TRI-STATE AREA TODAY. TONIGHT A COLD FRONT WILL MOVE THROUGH DURING
THE OVERNIGHT HOURS AHEAD OF AN UPPER LEVEL TROUGH THAT WILL MOVE
THROUGH MONDAY NIGHT. A SHALLOW LAYER OF MOISTURE WILL DEVELOP AS
THE COOLER AIR MOVES INTO THE AREA...CAUSING SOME CLOUDS TO
DEVELOP.
MONDAY...MOISTURE AND LIFT BEGIN TO MOVE INTO THE AREA FROM THE
NORTHWEST AHEAD OF THE UPPER LEVEL TROUGH DURING THE LATE
AFTERNOON...ALLOWING FOR SOME SLIGHT CHANCES FOR SNOWFALL FOR
MAINLY YUMA COUNTY.
MONDAY NIGHT...MOISTURE AND LIFT WILL MOVE OVER MOST OF THE AREA.
MODELS CONTINUE TO INDICATE THE BEST LIFT WILL GENERALLY BE AHEAD OF
THE BULK OF THE MOISTURE...WITH THE BEST COLLOCATION OF LIFT AND
MOISTURE DURING THE EVENING HOURS MAINLY NORTH OF HIGHWAY 24.
INCLUDED PRECIP. CHANCES FOR THE ENTIRE AREA DUE TO SOME
UNCERTAINTY IN THE TIMING AND STRENGTH OF THE LIFT AS IT MOVES
THROUGH. OVERNIGHT THE SNOWFALL LOOKS TO COME TO AN END FROM WEST
TO EAST AS THE UPPER LEVEL TROUGH MOVES THROUGH THE AREA. THE HILL
CITY AND NORTON AREAS MAY SEE SOME SNOW DURING THE OVERNIGHT HOURS...WITH
THE REST OF THE AREA LIKELY TO SEE SOME FLURRIES AS THE UPPER
LEVEL TROUGH MOVES EAST OUT OF THE AREA. WITH THE SREF CON TINING
TO PLACE THE BETTER CHANCES OVER NORTHERN NEBRASKA AND THE
MOISTURE MOVING IN BEHIND THE MAIN AREA OF LIFT...WILL CONTINUE
WITH LIGHT TOTAL SNOWFALL ACCUMULATIONS OF AN INCH OR LESS. MODELS
ALSO UNSURE OF THE STRENGTH OF THE WINDS AS THE SURFACE LOW MOVES
THROUGH DURING THE NIGHT. TRENDED THE WINDS TOWARD THE STRONGER
SOLUTIONS AS NAM AND GFS MSL PRESSURE PLOTS SHOW A STRONG GRADIENT
OVER THE AREA AS THE LOW MOVES THROUGH.
TUESDAY DRIER AIR AND A SURFACE HIGH PRESSURE MOVE INTO THE AREA.
HIGH TEMPERATURES FOR THE PERIOD WILL BE THE WARMEST TODAY. EASTERN
COLORADO WILL HAVE NEAR RECORD TEMPERATURES TODAY. THERE ARE SOME
CLOUDS MOVING IN FROM THE NORTHWEST...SO THESE WILL HAVE SOME AFFECT
ON HOW WARM TEMPERATURES WILL BE FOR THE WESTERN AREAS. MONDAY
TEMPERATURES WILL BE NEAR TO BELOW NORMAL AS COOLER AIR COMES IN
FROM THE NORTHEAST. THE CHEYENNE WELLS TO LEOTI AREA MAY HAVE
TEMPERATURES NEAR 50 IF THE FRONT DOES NOT MOVE THROUGH UNTIL LATE
AFTERNOON. TUESDAY TEMPERATURES WILL BE BELOW NORMAL.
LOW TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL TONIGHT AS THE COOLER
AIR BEGINS TO MOVE IN. MONDAY NIGHT LOWS WILL BE IN THE LOWER TO
MID TEENS AS BRISK NORTH WINDS CONTINUE TO BRING COOLER AIR INTO THE
AREA. TUESDAY NIGHT TEMPERATURES WILL BE NEAR NORMAL DESPITE THE
MOSTLY CLEAR SKIES AND DRY AIR.
JTL
.LONG TERM (WEDNESDAY-SATURDAY)...
257 AM MST SUN JAN 15 2012
NORTHWEST FLOW WILL PREVAIL ACROSS THE CENTRAL PLAINS THROUGH
FRIDAY. UPPER FLOW TRANSITIONS TO SOUTHWEST FLOW SATURDAY AS A
TROUGH DIGS INTO THE PACIFIC NORTHWEST. A SURFACE TROUGH WILL
PERSIST OVER EASTERN COLORADO THROUGH THURSDAY NIGHT AND THEN
SHIFT EAST FRIDAY. ANOTHER TROUGH WILL MOVE INTO EASTERN COLORADO
SATURDAY. DISTURBANCES COME THROUGH THE FLOW BUT LACK OF MOISTURE
WILL KEEP POPS NIL. MAX TEMPERATURES WILL RANGE FROM THE MID 40S
WEDNESDAY TO THE MID/UPPER 50S SATURDAY. MIN TEMPERATURES WILL
RANGE FROM THE MID/UPPER 20S WEDNESDAY NIGHT TO LOWER 30S SATURDAY
NIGHT.
FS
&&
.AVIATION...
1010 PM MST SAT JAN 14 2012
SURFACE HIGH PRESSURE WILL SLIDE INTO THE EASTERN CONUS AS A LEE
TROUGH DEVELOPS AND DEEPENS TO OUR WEST. IN THE UPPER
LEVELS...HIGH PRESSURE RIDGE WILL MOVE OVER THE AREA THIS PERIOD
WITH A TROUGH MOVING INTO THE INTERMOUNTAIN WEST. VFR CONDITIONS
ARE EXPECTED DURING THIS PERIOD WITH HIGH CIRRUS MOVING OVER THE
AREA FROM TIME TO TIME. SURFACE WINDS WILL BE FROM THE SOUTHWEST
EARLY THEN SWITCHING TO THE WEST. TOWARDS THE END OF THE
PERIOD...WINDS WILL BECOME LIGHT AND VARIABLE AS THE PRESSURE
GRADIENT WEAKENS.
BAS
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
407 AM CST SUN JAN 15 2012
.DISCUSSION...
SHORT RANGE (TODAY AND MONDAY)...
09Z WATER VAPOR IMAGERY AND RUC ANALYSIS INDICATES TWO UPPER TROUGHS
OVER THE CONUS. ONE IS LOCATED ROUGHLY OVER THE NEW ENGLAND
STATES..WITH THE OTHER JUST COMING ON SHORE OVER THE PACIFIC
NORTHWEST. BETWEEN THESE TWO TROUGHS IS A FLEETING UPPER RIDGE WHICH
WILL TRANSIT ACROSS THE AREA THROUGH THE DAY TODAY. STRONG SOUTHERLY
WINDS WILL PICK UP IN INTENSITY TODAY IN RESPONSE TO A NORTH-SOUTH
ELONGATED SURFACE TROUGH WHICH WILL MOVE OFF THE NORTHERN ROCKIES
TODAY. EXPECT THE SOUTHERLY WINDS TO REACH THE 20 TO 30 MPH
RANGE...WITH GUSTS OF UP TO 35 MPH. WARM AIR ADVECTION ASSOCIATED
WITH THE SOUTHERLY FLOW IN CONJUNCTION WITH THE QUICKLY MOVING
RIDGE WILL BRING A CLEAR AND UNSEASONABLY WARM DAY TO NORTHEAST
KANSAS. EXPECT ONLY SHALLOW MIXING TODAY WITH A STRONG INVERSION
EXPECTED TO SET UP NEAR THE 925 MB LEVEL...BUT DRY AIR JUST OFF
THE SURFACE WILL BE ALLOWED TO MIX TO THE SURFACE CAUSING DRY
CONDITIONS TODAY...LENDING TO AN ENHANCED FIRE DANGER TODAY. WILL
NEED TO CONTINUE TO MONITOR THE CONDITIONS AS THE DAY WEARS ON AND
MAKE ADJUSTMENTS TO THE FORECAST AS NECESSARY.
THE WARM UP WILL NOT LAST LONG AS A STRONG COLD FRONT WILL MOVE INTO
THE AREA ON MONDAY EVENING. PORTIONS OF EAST CENTRAL KANSAS WILL
LIKELY SEE ANOTHER DAY OF UPPER 50 TO LOWER 60 DEGREE TEMPS ON
MONDAY AS THOSE AREAS WILL REMAIN AHEAD OF THE COLD FRONT. AREAS
BEHIND THE FRONT...NAMELY AREAS NORTH AND WEST OF THE KANSAS
TURNPIKE...WILL LIKELY ONLY SEE HIGHS IN THE LOWER TO MID 40S ON
MONDAY. ON MONDAY NIGHT THE PARENT MID TO UPPER LEVEL TROUGH WILL
PASS THROUGH THE NORTHERN PLAINS...CAUSING THE MOST SIGNIFICANT LIFT
TO REMAIN NORTH OF THE KS/NE BORDER. WITH THE MARGINAL LIFT AND DRY
AIR OVER NORTHEAST KANSAS DO NOT EXPECT VERY MUCH PRECIPITATION FROM
THIS SYSTEM. THE AREA WITH THE BEST CHANCE FOR ANY PRECIP ON MONDAY
NIGHT WILL BE EXTREME NORTH CENTRAL AND NORTHEASTERN KANSAS...MAINLY
ALONG HIGHWAY 36...BUT EVEN THESE AREAS ARE NOT EXPECTED TO SEE MUCH
MORE THAN SOME FLURRIES OR OCCASIONAL LIGHT SNOW WITH LITTLE TO NO
ACCUMULATION EXPECTED.
MID RANGE AND EXTENDED FORECAST (TUESDAY THROUGH SATURDAY)...
BY TUESDAY STRONG NORTHERLY WINDS OF 20 TO 30 MPH WILL USHER IN
ANOTHER ARCTIC AIR MASS INTO THE THE CENTRAL PLAINS. WITH THE COLD
AIR BECOMING FIRMLY ENTRENCHED OVER THE AREA EXPECT TEMPS ON TUESDAY
TO MAX OUT IN THE UPPER 20S TO LOWER 30S ACROSS ALL OF NORTHEAST
KANSAS. WEDNESDAY NIGHT WILL LIKELY BE THE COLDEST PERIOD OF THIS
FORECAST AS THE SURFACE RIDGE BECOMES CENTERED OVER THE AREAS
CAUSING THE OVERNIGHT LOWS TO FALL TO THE LOWER TO MID TEENS. BY WED
ANOTHER BRIEF WARM UP IS EXPECTED AS SOUTH-SOUTHWEST WINDS BRING WARM
AIR BACK INTO THE AREA. EXPECT ANOTHER MILD DAY ON WED WITH TEMPS
MAXING OUT IN THE MID TO UPPER 40S. EXPECT THE GRADUAL WARM UP TO
CONTINUE THROUGH THE END OF THE WEEK BRINGING MILD CONDITIONS TO THE
AREA.
JL
&&
.AVIATION...
VFR CONDITIONS SHOULD HOLD THROUGH 06Z SUNDAY. WILL GO AHEAD WITH
LLWS MENTION IN THE 09Z-18Z PERIOD GIVEN QUICK INCREASES WITH
HEIGHT PER MODEL SOUNDINGS AND WINDS INCREASING IN UPSTREAM
PROFILERS. MAY HAVE LLWS RETURN BY 03Z MONDAY BUT TOO SOON TO
NAIL DOWN. ONLY SOME CIRRUS EXPECTED.
65
&&
.FIRE WEATHER...
EXPECT SOUTHERLY WINDS TODAY TO INCREASE TO 15 TO 25 MPH WITH
GUSTS OF UP TO 35 MPH. EXPECT THE STRONGEST WINDS TO BE ACROSS
AREAS EAST OF A MARYSVILLE TO COUNCIL GROVE LINE...HOWEVER EVEN
AREAS WEST OF THIS LINE COULD SEE WINDS OF 15 TO 25 MPH TODAY.
MIXING WILL BE FAIRLY SHALLOW ON SUNDAY...HOWEVER THE SOUTHERLY
WINDS WILL ADVECT AIR FROM ACROSS SOUTHERN MISSOURI...EASTERN
OKLAHOMA...AND WESTERN ARKANSAS NORTHWARD INTO EASTERN KANSAS.
CURRENTLY THE DEWPOINTS OF THIS AIRMASS ARE IN THE LOWER TO MID 20
DEGREE RANGE...SO FEEL THAT DEWPOINTS ACROSS THE AREA WILL NOT
REACH MUCH HIGHER THAN 25 DEGREES...WHICH IN COMBINATION WITH THE
LOWER 60 DEGREE AIR WILL YIELD MIN RH VALUES IN THE LOWER TO MID
20 PERCENT RANGE FOR THIS AFTERNOON. AS A RESULT OF THESE
CONDITIONS VERY HIGH FIRE DANGER WILL EXIST ACROSS PARTS OF THE
AREA FOR TODAY. CONDITIONS WILL NEED TO BE MONITORED THROUGHOUT
THE DAY IN CASE THE AIR DRIES OUT MORE THAN EXPECTED.
JL
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
712 AM CST SUN JAN 15 2012
.UPDATE...
.SHORT TERM...
A LOOK AT THE MORNING UA FLIGHTS FROM LBF...UNR AND DNR AS WELL AS
THE RUC...GEM REG AND HRRR FORECAST TEMPS SUGGESTED RAISING 1ST
PERIOD MAX TEMPS A FEW DEGREES. WITH DEEPER VERTICAL MIXING TO
850 MB THESE TEMPS SHOULD BE REACHABLE AND STRONGER WINDS NEAR THE
BREEZY CATEGORY SHOULD DEVELOP AS WINDS AT H850 ARE FCST TO REACH 30
TO 35 KTS.
THE HRRR SUGGESTED RED FLAG CONDITIONS BUT A BLEND OF HRRR AND
DRIER MAV GUIDANCE USING THE WARMER HIGHS ONLY PRODUCED RH NEAR 20
PERCENT SO THE UPDATED FCST DOES NOT INCLUDE A RED FLAG WARNING.
.PREV DISCUSSION... /ISSUED 519 AM CST SUN JAN 15 2012/
UPDATE...
AVIATION...
VFR IS EXPECTED TODAY. AN ARCTIC FRONT WILL DROP THROUGH THE
FORECAST AREA TONIGHT. CURRENT INDICATIONS ARE MVFR CIGS COULD
DEVELOP FROM NORTH TO SOUTH AFTER 09Z.
PREV DISCUSSION... /ISSUED 400 AM CST SUN JAN 15 2012/
SHORT TERM...TODAY THROUGH TUESDAY NIGHT
FORECAST CONCERNS THROUGH THIS PERIOD DEAL WITH SNOW CHANCES
MONDAY AND MONDAY NIGHT AS WELL AS TEMPERATURES THROUGHOUT THE PERIOD.
AT 08Z WATER VAPOR IMAGERY SHOWED RIDGING OVER THE CENTRAL AND
NORTHERN PLAINS AS A SHORTWAVE TROUGH MOVED INTO THE PACIFIC
NORTHWEST WITH AN ENHANCED BIT OF ENERGY PLACED OVER SOUTHERN SASKATCHEWAN.
MEANWHILE ANOTHER CIRCULATION WAS OBSERVED OFF THE CALIFORNIA
COAST IN THE SOUTHERN STREAM. CLOSER TO HOME...THERE WERE A FEW
CLOUDS SEEN OVER THE FORECAST AREA EARLY THIS MORNING MOVING OVER
THE RIDGE...AND WITH WARM AIR PUSHING IN...TEMPERATURES STAYED
MILD FOR THIS TIME OF YEAR. AT 08Z...OBSERVATIONS INDICATED MID
20S TO LOW 30S ACROSS MUCH OF NEBRASKA. PLENTIFUL WARM AIR
ADVECTION HAS BEEN TAKING PLACE OVERNIGHT AS COMPARING LAPS
SOUNDINGS TO THE KLBF SOUNDING FROM 15.00Z WOULD SHOW AN INCREASE
IN TEMPERATURES BETWEEN 800 TO 850MB OF AROUND 9 DEGREES FROM 00Z
TO 07Z.
BUFKIT FORECAST SOUNDINGS FROM BOTH THE NAM/GFS ARE NOT HANDLING THE
WARM AIR PATTERN FOR TODAY WELL AS THEY FAILED TO MIX OUT THE
BOUNDARY LAYER THIS AFTERNOON. THIS HAS BEEN A PROBLEM IN THE PAST
WHICH HAS FORECASTED TEMPERATURES MUCH TOO COLD...SO DID NOT LOOK AT
THESE MODELS FOR TEMPERATURES TODAY. FROM THE FORECAST SOUNDINGS
ASSUMING MIXING TO 850 OR 875MB WOULD BRING TEMPERATURES THIS
AFTERNOON INTO THE 60S ACROSS MUCH OF SOUTHWEST INTO CENTRAL
NEBRASKA. THESE NUMBERS WILL BE WELL ABOVE NORMAL...BUT DON/T
EXPECT TO REACH RECORD NUMBERS TODAY. CONFIDENCE ROSE IN THAT LAST
STATEMENT AS STANDARDIZED ANOMALY DATA SHOWED 850MB TEMPERATURES
AT 1.5 STANDARD DEVIATIONS ABOVE NORMAL. WOULD LIKE THAT TO BE
HIGHER IF FORECASTING RECORD NUMBERS. WINDS AT THE TOP OF THE
MIXED LAYER WILL ONLY BE 15 TO 20KTS SO DON/T EXPECT WINDS TO BE
TOO STRONG TODAY. THIS IS A POSITIVE IN TERMS OF FIRE WEATHER
CONCERNS AS RELATIVE HUMIDITY WILL BE LOW TODAY. SEE FIRE WEATHER
DISCUSSION BELOW FOR MORE DETAILS.
AS TODAY PROGRESSES...THE SHORTWAVE TROUGH OVER THE PACIFIC
NORTHWEST WILL MOVE EAST TOWARDS THE NORTHERN ROCKIES WITH THEA
SHORTWAVE TROUGH OVER SASKATCHEWAN WILL MOVE EAST ACROSS SOUTHERN
CANADA. THIS WILL LEAD TO A SURFACE FRONT CENTERED OVER SOUTHERN
CANADA TO ALSO MOVE EAST...DRAGGING ALONG A COLD FRONT ACROSS THE
PLAINS. THE TIMING OF THE FRONT WILL BE TO MOVE INTO NORTHWEST
NEBRASKA LATER THIS AFTERNOON...SO HIGH TEMPERATURES SHOULD SEE
LITTLE AFFECT FROM COLDER AIR COMING SOUTH.
TEMPERATURES TONIGHT WILL DROP SIGNIFICANTLY AS HIGH PRESSURE
BUILDS IN FROM THE NORTH TO WEAKEN THE WINDS AND PUSH ANY CLOUDS
OUT OF THE AREA /ESPECIALLY OVER THE PANHANDLE/. ONGOING FORECAST
IS A BIT WARMER THAN SOME STATISTICAL GUIDANCE...WITH THE
UNCERTAINTY IN THE DROP OFF OF WINDS TO IMPACT THE FORECAST LOWS.
THE MAIN PACIFIC NORTHWEST SHORTWAVE WILL PASS ACROSS THE ROCKY
MOUNTAINS BY MONDAY MORNING AND INTO THE NORTHERN AND CENTRAL
PLAINS THROUGH THE DAY MONDAY. THIS SYSTEM WILL BRING SNOW CHANCES
TO THE FORECAST AREA FOR MONDAY AND MONDAY NIGHT. DID BACK OFF A
BIT ON SNOW CHANCES MONDAY MORNING AS A SUBSTANTIAL DRY LAYER
LOOKS TO BE IN PLACE ACCORDING TO CROSS SECTIONS AND FORECAST
SOUNDINGS TO SLOW THE ONSET OF PRECIPITATION AS THE COLUMN
SATURATES. HIGHEST CHANCES ARE GOING TO COME AFTER 18Z MONDAY
THROUGH 17.06Z AS THE COLUMN IS SATURATED AND COMBINES WITH THE
STRONGEST UPPER LEVEL DYNAMICS AS WELL A FRONTOGENESIS SIGNAL IN
THE 700 TO 600MB LAYER. THE SYSTEM AS A WHOLE WILL HAVE QUITE A
BIT OF MOISTURE WITH IT...BUT A GREAT DEAL OF THAT MOISTURE WILL
BE SQUEEZED OUT AS IT OVERPASSES THE MOUNTAINS. THUS ONLY LOOKING
FOR LIGHT SNOW AMOUNTS FOR MONDAY AND MONDAY NIGHT. AS MUCH COOLER
AIR WILL BE IN PLACE ALOFT...HIGHS MONDAY WILL BE SOME 30 DEGREES
COOLER THAN WHAT OCCURRED SUNDAY. MONDAY NIGHT IS LOOKING TO BE
THE COLDEST NIGHT OF THE WEEK AS 850MB TEMPERATURES DROP TO 12 TO
15 DEGREES BELOW ZERO. THERE DOES REMAIN SOME UNCERTAINTY TO HOW
FAR TO DROP LOWS THIS PERIOD AS CLOUDS MAY REMAIN DUE TO A
DEPARTING SHORTWAVE TROUGH AND WINDS ACROSS CENTRAL NEBRASKA STAY
BREEZY. LOCATIONS OVER THE PANHANDLE SHOULD SEE THE COLDEST
TEMPERATURES AS SKIES CLEAR AND WINDS DECREASE.
TEMPERATURES ARE FORECAST TO BE NEAR NORMAL FOR TUESDAY ALTHOUGH
WARM AID ADVECTION WILL START UP AGAIN DURING THE DAY. THIS REALLY
DOESN/T KICK IN UNTIL LATER IN THE DAY SO WON/T BE TOO QUICK TO
RAISE HIGHS.
LONG TERM...WEDNESDAY THROUGH SATURDAY
THIS PERIOD OF THE FORECAST CONTINUES TO SEE MUCH UNCERTAINTY AS
IT RELIES HEAVILY ON THE PLACEMENT OF A SURFACE FRONTAL BOUNDARY
TO DELINEATE WHERE THE MUCH COLDER TEMPERATURES WILL BE IN PLACE
WHILE LOCATIONS TO THE SOUTH OF THE FRONT WILL SEE CONDITIONS STAY
ABOVE NORMAL. ALTHOUGH THERE ARE DIFFERENCES BETWEEN MODEL
SOLUTIONS...THE MAIN CONSENSUS IS TO KEEP THE COLDER (-20C OR
COLDER AIR AT 850MB OVER THE DAKOTAS AND WELL NORTH OF THE
FORECAST AREA. THERE WILL BE A TIGHT TEMPERATURE GRADIENT SO AS
THIS AIR MAY COME INTO NORTHERN NEBRASKA...MAY SEE A TEMPERATURE
RANGE ACROSS THE FORECAST AREA FROM THE MID 20S TO THE MID 50S.
THE FLOW THROUGH THIS TIME WILL BE QUICK NORTHWEST FLOW AND THERE
DOES LOOK TO BE POTENTIAL FOR A QUICK SHOT OF PRECIPITATION
THURSDAY NIGHT. KEPT THE MENTION OF THIS TO THE FAR NORTHEAST
PORTIONS OF THE FORECAST AREA AS THERE IS LOW CONFIDENCE BUT HARD
TO PULL CHANCES WITH SEVERAL MODEL SOLUTIONS PUSHING A TROUGH
ACROSS THE AREA.
AVIATION...
VFR IS EXPECTED TODAY AND TONIGHT. AN ARCTIC FRONT IS EXPECTED TO
DROP THROUGH THE FORECAST AREA TONIGHT. CURRENT INDICATIONS ARE MVFR
CIGS WILL NOT DEVELOP UNTIL AFTER 12Z MONDAY MORNING.
FIRE WEATHER...
ALTHOUGH DEWPOINTS ARE FORECAST TO SLOWLY RISE THROUGH THE
DAY...THE COMBINATION WITH THE ABNORMAL WARM TEMPERATURES WILL
DROP RELATIVE HUMIDITY DOWN TO 15 TO 25 PERCENT ACROSS MUCH OF
WESTERN AND NORTH CENTRAL NEBRASKA. FUELS CONTINUE TO BE PRIMED
FOR BURNING DUE TO THE LACK OF PRECIPITATION OVER THE LAST SEVERAL
WEEKS SO THOSE WITH FIRE CONCERNS ARE URGED TO PAY CLOSE ATTENTION
TO CURRENT CONDITIONS AT YOUR SITE. WINDS LOOK TO STAY BELOW RED
FLAG WARNING CRITERIA SO WILL TO EXPECT NEAR CRITICAL CONDITIONS
FOR FIRE WEATHER. ALSO...EVEN IF A SITE OR TWO DOES HIT RED FLAG
CRITERIA...DON/T EXPECT IT TO LAST 3 HOURS OR MORE SO WILL STICK
WITH NO HAZARD PRODUCT FOR FIRE WEATHER CONCERNS TODAY.
HYDROLOGY...
ICE JAM PROBLEMS CONTINUE ALONG THE NORTH PLATTE RIVER BETWEEN
LEWELLEN AND LAKE MCCONAUGHY. THE WARM TEMPERATURES TODAY MAY HELP
TO BREAK UP SOME OF THE ICE AND ALLEVIATE THE FLOODING...HOWEVER
THE COLD /BELOW FREEZING/ TEMPERATURES FORECAST FOR THE FIRST FEW
DAYS OF THE WORK WEEK WILL LIKELY CAUSE MORE BUILDUP OF ICE TO
PROLONG THE ICE JAM FLOODING IN THIS AREA. IN ADDITION...OTHER
AREAS ALONG THE NORTH PLATTE RIVER MAY SEE ICE JAMMING OCCUR THIS
WEEK.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/EXTENDED...BROOKS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1100 AM MST SUN JAN 15 2012
.SYNOPSIS...
257 AM MST SUN JAN 15 2012
LATEST SATELLITE IMAGERY AND RUC UPPER AIR ANALYSIS SHOWED
NORTHWESTERLY UPPER LEVEL FLOW TURNING TO THE WEST AS AN UPPER
LEVEL RIDGE MOVES OVER THE CENTRAL PLAINS. AT THE SURFACE A TROUGH
OF LOW PRESSURE WAS PROGRESSING EAST ACROSS THE TRI-STATE
AREA...CAUSING THE SOUTHWEST WINDS TO SHIFT TO THE WEST BEHIND IT.
JTL
&&
.SHORT TERM (TODAY-TUESDAY)...
257 AM MST SUN JAN 15 2012
MAIN FOCUS WILL BE SNOWFALL CHANCES WITH THE COLD FRONT ON MONDAY
AND MONDAY NIGHT.
TODAY AND TONIGHT...AN UPPER LEVEL RIDGE WILL BUILD INTO THE
TRI-STATE AREA TODAY. TONIGHT A COLD FRONT WILL MOVE THROUGH DURING
THE OVERNIGHT HOURS AHEAD OF AN UPPER LEVEL TROUGH THAT WILL MOVE
THROUGH MONDAY NIGHT. A SHALLOW LAYER OF MOISTURE WILL DEVELOP AS
THE COOLER AIR MOVES INTO THE AREA...CAUSING SOME CLOUDS TO
DEVELOP.
MONDAY...MOISTURE AND LIFT BEGIN TO MOVE INTO THE AREA FROM THE
NORTHWEST AHEAD OF THE UPPER LEVEL TROUGH DURING THE LATE
AFTERNOON...ALLOWING FOR SOME SLIGHT CHANCES FOR SNOWFALL FOR
MAINLY YUMA COUNTY.
MONDAY NIGHT...MOISTURE AND LIFT WILL MOVE OVER MOST OF THE AREA.
MODELS CONTINUE TO INDICATE THE BEST LIFT WILL GENERALLY BE AHEAD OF
THE BULK OF THE MOISTURE...WITH THE BEST COLLOCATION OF LIFT AND
MOISTURE DURING THE EVENING HOURS MAINLY NORTH OF HIGHWAY 24.
INCLUDED PRECIP. CHANCES FOR THE ENTIRE AREA DUE TO SOME
UNCERTAINTY IN THE TIMING AND STRENGTH OF THE LIFT AS IT MOVES
THROUGH. OVERNIGHT THE SNOWFALL LOOKS TO COME TO AN END FROM WEST
TO EAST AS THE UPPER LEVEL TROUGH MOVES THROUGH THE AREA. THE HILL
CITY AND NORTON AREAS MAY SEE SOME SNOW DURING THE OVERNIGHT HOURS...WITH
THE REST OF THE AREA LIKELY TO SEE SOME FLURRIES AS THE UPPER
LEVEL TROUGH MOVES EAST OUT OF THE AREA. WITH THE SREF CON TINING
TO PLACE THE BETTER CHANCES OVER NORTHERN NEBRASKA AND THE
MOISTURE MOVING IN BEHIND THE MAIN AREA OF LIFT...WILL CONTINUE
WITH LIGHT TOTAL SNOWFALL ACCUMULATIONS OF AN INCH OR LESS. MODELS
ALSO UNSURE OF THE STRENGTH OF THE WINDS AS THE SURFACE LOW MOVES
THROUGH DURING THE NIGHT. TRENDED THE WINDS TOWARD THE STRONGER
SOLUTIONS AS NAM AND GFS MSL PRESSURE PLOTS SHOW A STRONG GRADIENT
OVER THE AREA AS THE LOW MOVES THROUGH.
TUESDAY DRIER AIR AND A SURFACE HIGH PRESSURE MOVE INTO THE AREA.
HIGH TEMPERATURES FOR THE PERIOD WILL BE THE WARMEST TODAY. EASTERN
COLORADO WILL HAVE NEAR RECORD TEMPERATURES TODAY. THERE ARE SOME
CLOUDS MOVING IN FROM THE NORTHWEST...SO THESE WILL HAVE SOME AFFECT
ON HOW WARM TEMPERATURES WILL BE FOR THE WESTERN AREAS. MONDAY
TEMPERATURES WILL BE NEAR TO BELOW NORMAL AS COOLER AIR COMES IN
FROM THE NORTHEAST. THE CHEYENNE WELLS TO LEOTI AREA MAY HAVE
TEMPERATURES NEAR 50 IF THE FRONT DOES NOT MOVE THROUGH UNTIL LATE
AFTERNOON. TUESDAY TEMPERATURES WILL BE BELOW NORMAL.
LOW TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL TONIGHT AS THE COOLER
AIR BEGINS TO MOVE IN. MONDAY NIGHT LOWS WILL BE IN THE LOWER TO
MID TEENS AS BRISK NORTH WINDS CONTINUE TO BRING COOLER AIR INTO THE
AREA. TUESDAY NIGHT TEMPERATURES WILL BE NEAR NORMAL DESPITE THE
MOSTLY CLEAR SKIES AND DRY AIR.
JTL
.LONG TERM (WEDNESDAY-SATURDAY)...
257 AM MST SUN JAN 15 2012
NORTHWEST FLOW WILL PREVAIL ACROSS THE CENTRAL PLAINS THROUGH
FRIDAY. UPPER FLOW TRANSITIONS TO SOUTHWEST FLOW SATURDAY AS A
TROUGH DIGS INTO THE PACIFIC NORTHWEST. A SURFACE TROUGH WILL
PERSIST OVER EASTERN COLORADO THROUGH THURSDAY NIGHT AND THEN
SHIFT EAST FRIDAY. ANOTHER TROUGH WILL MOVE INTO EASTERN COLORADO
SATURDAY. DISTURBANCES COME THROUGH THE FLOW BUT LACK OF MOISTURE
WILL KEEP POPS NIL. MAX TEMPERATURES WILL RANGE FROM THE MID 40S
WEDNESDAY TO THE MID/UPPER 50S SATURDAY. MIN TEMPERATURES WILL
RANGE FROM THE MID/UPPER 20S WEDNESDAY NIGHT TO LOWER 30S SATURDAY
NIGHT.
FS
&&
.AVIATION...
1057 AM MST SUN JAN 15 2012
FOR THE 18Z TAF...VFR CONDITIONS WILL PREVAIL AT BOTH KGLD AND
KMCK THROUGH THE EFFECTIVE PERIOD. WINDS WILL BE GENERALLY LIGHT
AND VARIABLE BEFORE A COLD FRONT MOVES THROUGH THE REGION AROUND
06Z. NOT EXPECTING MUCH OF AN INCREASE IN WIND SPEEDS AT KGLD BUT
COULD SEE WINDS APPROACH 12KTS OUT OF THE NORTH-NORTHEAST AT KMCK
BEHIND THE FRONT. LITTLE MORE THAN A BAND OF MID/UPPER LEVEL
CLOUDS TO DEAL WITH THROUGH THE NEXT 24 HOURS.
FOLTZ
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1145 AM CST SUN JAN 15 2012
...UPDATE TO AVIATION...
.DISCUSSION...
SHORT RANGE (TODAY AND MONDAY)...
09Z WATER VAPOR IMAGERY AND RUC ANALYSIS INDICATES TWO UPPER TROUGHS
OVER THE CONUS. ONE IS LOCATED ROUGHLY OVER THE NEW ENGLAND
STATES..WITH THE OTHER JUST COMING ON SHORE OVER THE PACIFIC
NORTHWEST. BETWEEN THESE TWO TROUGHS IS A FLEETING UPPER RIDGE WHICH
WILL TRANSIT ACROSS THE AREA THROUGH THE DAY TODAY. STRONG SOUTHERLY
WINDS WILL PICK UP IN INTENSITY TODAY IN RESPONSE TO A NORTH-SOUTH
ELONGATED SURFACE TROUGH WHICH WILL MOVE OFF THE NORTHERN ROCKIES
TODAY. EXPECT THE SOUTHERLY WINDS TO REACH THE 20 TO 30 MPH
RANGE...WITH GUSTS OF UP TO 35 MPH. WARM AIR ADVECTION ASSOCIATED
WITH THE SOUTHERLY FLOW IN CONJUNCTION WITH THE QUICKLY MOVING
RIDGE WILL BRING A CLEAR AND UNSEASONABLY WARM DAY TO NORTHEAST
KANSAS. EXPECT ONLY SHALLOW MIXING TODAY WITH A STRONG INVERSION
EXPECTED TO SET UP NEAR THE 925 MB LEVEL...BUT DRY AIR JUST OFF
THE SURFACE WILL BE ALLOWED TO MIX TO THE SURFACE CAUSING DRY
CONDITIONS TODAY...LENDING TO AN ENHANCED FIRE DANGER TODAY. WILL
NEED TO CONTINUE TO MONITOR THE CONDITIONS AS THE DAY WEARS ON AND
MAKE ADJUSTMENTS TO THE FORECAST AS NECESSARY.
THE WARM UP WILL NOT LAST LONG AS A STRONG COLD FRONT WILL MOVE INTO
THE AREA ON MONDAY EVENING. PORTIONS OF EAST CENTRAL KANSAS WILL
LIKELY SEE ANOTHER DAY OF UPPER 50 TO LOWER 60 DEGREE TEMPS ON
MONDAY AS THOSE AREAS WILL REMAIN AHEAD OF THE COLD FRONT. AREAS
BEHIND THE FRONT...NAMELY AREAS NORTH AND WEST OF THE KANSAS
TURNPIKE...WILL LIKELY ONLY SEE HIGHS IN THE LOWER TO MID 40S ON
MONDAY. ON MONDAY NIGHT THE PARENT MID TO UPPER LEVEL TROUGH WILL
PASS THROUGH THE NORTHERN PLAINS...CAUSING THE MOST SIGNIFICANT LIFT
TO REMAIN NORTH OF THE KS/NE BORDER. WITH THE MARGINAL LIFT AND DRY
AIR OVER NORTHEAST KANSAS DO NOT EXPECT VERY MUCH PRECIPITATION FROM
THIS SYSTEM. THE AREA WITH THE BEST CHANCE FOR ANY PRECIP ON MONDAY
NIGHT WILL BE EXTREME NORTH CENTRAL AND NORTHEASTERN KANSAS...MAINLY
ALONG HIGHWAY 36...BUT EVEN THESE AREAS ARE NOT EXPECTED TO SEE MUCH
MORE THAN SOME FLURRIES OR OCCASIONAL LIGHT SNOW WITH LITTLE TO NO
ACCUMULATION EXPECTED.
MID RANGE AND EXTENDED FORECAST (TUESDAY THROUGH SATURDAY)...
BY TUESDAY STRONG NORTHERLY WINDS OF 20 TO 30 MPH WILL USHER IN
ANOTHER ARCTIC AIR MASS INTO THE THE CENTRAL PLAINS. WITH THE COLD
AIR BECOMING FIRMLY ENTRENCHED OVER THE AREA EXPECT TEMPS ON TUESDAY
TO MAX OUT IN THE UPPER 20S TO LOWER 30S ACROSS ALL OF NORTHEAST
KANSAS. WEDNESDAY NIGHT WILL LIKELY BE THE COLDEST PERIOD OF THIS
FORECAST AS THE SURFACE RIDGE BECOMES CENTERED OVER THE AREAS
CAUSING THE OVERNIGHT LOWS TO FALL TO THE LOWER TO MID TEENS. BY WED
ANOTHER BRIEF WARM UP IS EXPECTED AS SOUTH-SOUTHWEST WINDS BRING WARM
AIR BACK INTO THE AREA. EXPECT ANOTHER MILD DAY ON WED WITH TEMPS
MAXING OUT IN THE MID TO UPPER 40S. EXPECT THE GRADUAL WARM UP TO
CONTINUE THROUGH THE END OF THE WEEK BRINGING MILD CONDITIONS TO THE
AREA.
JL
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
.AVIATION...
VFR CONDITIONS CURRENTLY ACROSS THE TERMINALS AND WILL CONTINUE
INTO THE OVERNIGHT HOURS. STRONG SOUTH TO SOUTHWEST WIND WILL
CONTINUE THIS AFTERNOON. LLWS COULD BE A CONCERN WITH WINDS AROUND
50 KTS AT 2 KFT AFTER 00Z TONIGHT. HOWEVER...WITH UNIDIRECTIONAL
FLOW UP TO 2 KFT DID NOT INCLUDE IN TAF. LOW LEVEL MOISTURE WILL
INCREASE AHEAD OF THE FRONT WITH MVFR CEILINGS MOVING INTO KTOP AND
KFOE AROUND 08Z.
ANDERSON
&&
.FIRE WEATHER...
EXPECT SOUTHERLY WINDS TODAY TO INCREASE TO 15 TO 25 MPH WITH
GUSTS OF UP TO 35 MPH. EXPECT THE STRONGEST WINDS TO BE ACROSS
AREAS EAST OF A MARYSVILLE TO COUNCIL GROVE LINE...HOWEVER EVEN
AREAS WEST OF THIS LINE COULD SEE WINDS OF 15 TO 25 MPH TODAY.
MIXING WILL BE FAIRLY SHALLOW ON SUNDAY...HOWEVER THE SOUTHERLY
WINDS WILL ADVECT AIR FROM ACROSS SOUTHERN MISSOURI...EASTERN
OKLAHOMA...AND WESTERN ARKANSAS NORTHWARD INTO EASTERN KANSAS.
CURRENTLY THE DEWPOINTS OF THIS AIRMASS ARE IN THE LOWER TO MID 20
DEGREE RANGE...SO FEEL THAT DEWPOINTS ACROSS THE AREA WILL NOT
REACH MUCH HIGHER THAN 25 DEGREES...WHICH IN COMBINATION WITH THE
LOWER 60 DEGREE AIR WILL YIELD MIN RH VALUES IN THE LOWER TO MID
20 PERCENT RANGE FOR THIS AFTERNOON. AS A RESULT OF THESE
CONDITIONS VERY HIGH FIRE DANGER WILL EXIST ACROSS PARTS OF THE
AREA FOR TODAY. CONDITIONS WILL NEED TO BE MONITORED THROUGHOUT
THE DAY IN CASE THE AIR DRIES OUT MORE THAN EXPECTED.
JL
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
415 PM EST SUN JAN 15 2012
.SHORT TERM /TONIGHT THROUGH MONDAY/...
LES CONTINUES OVER THE FAR EASTERN CWA...WITH VIS FALLING TO A MILE
AT TIMES AROUND 18Z THIS AFTERNOON AT ERY. THE LATEST SATELLITE
IMAGERY INDICATE THIS BAND SLOWLY SHIFTING WESTWARD INTO SCHOOLCRAFT
COUNTY. WHILE A QUICK HALF AN INCH OR SO AN HOUR COULD STILL BE
POSSIBLE IN THE STRONGEST PORTIONS OF THE BAND...THE MOBILE NATURE
SHOULD KEEP ACCUMULATIONS IN CHECK THIS AFTERNOON INTO THE EVENING
HOURS.
THE STRONG S-SW WINDS WILL BRING AN INFLUX OF WARM AIR TO THE REGION
OVERNIGHT. EXPECT 850MB TEMPS TO RISE INTO THE SINGLE DIGITS BELOW
ZERO...TOPPING OUT FROM THIS AFTERNOON MUCH OF THE PERIOD. EXTENT OF
THE WARM AIR SLIDING FROM EASTERN MN ACROSS N WI IS OF A
CONCERN...AS THE 15/15Z RUN OF THE RUC13 SHOWS TEMPS AROUND 0C NEAR
ID AS EARLY AS 03Z MONDAY /3 TO 5C WARMER THAN THE CONSENSUS/.
OTHERWISE...MOST OF THE WARM AIR SHOULD BE CONCENTRATED OVER THE
CENTRAL PORTIONS OF THE CWA...TOPPING OUT 15Z MONDAY AROUND 0C FROM
CENTRAL WI THROUGH DELTA AND SOUTHERN MARQUETTE COUNTIES. WHILE ONE
FCST MODEL DOES SPIT OUT LITE PRECIP OVER THIS AREA AS EARLY AS
EARLY AFTERNOON TODAY...THE REMAINDER OF THE MODELS HOLD OFF UNTIL
AFTER 03Z MONDAY. WILL FOLLOW THE LATER AND ONLY INCLUDE FLURRIES
FOR THE REMAINDER OF TODAY...AS A SFC COLD FRONT/TROUGH NEARS FROM
CENTRAL MN. IF ANYTHING DOES FALL IT WOULD LIKELY BE IN THE FORM OF
FZDZ OVERNIGHT...WITH THE BEST SNOW GROWTH LAYER AROUND 700MB AT
IMT...AND ALL THE MOISTURE STUCK BELOW THE INVERSION HOVERING AROUND
900MB. WILL KEEP THE MENTION OF FZDZ IN THE FCST AND THE HWO. LOW
CLOUDS REMAIN POSSIBLE...ESPECIALLY WITH THE WAA...AS MOISTURE
ESCAPES THE AVG 2-4 INCHES OF SNOW OVER N WI. DEW POINTS LOOK
MINIMAL FOR SIGNIFICANT MELTING THOUGH...EXPECTED TO REMAIN IN THE
LOW 20F RANGE AT BEST. THE BEST MOISTURE PLUME WILL LIKELY REMAIN
OFF LAKE MICHIGAN...SLIDING NE INTO MARQUETTE COUNTY BY LATE EVENING
BEFORE A MORE SW WIND TAKES HOLD.
AS FOR MONDAY...MUCH OF THE MOISTURE WILL SLIDE OUT OF THE CWA AS
WINDS TURN W AND NW THROUGH THE DAYTIME HOURS AS THE COLD FRONT
SHIFTS ACROSS. EXPECT THE SFC LOW TO BE OVER CENTRAL ONTARIO BY 12Z
MONDAY...WITH THE COLD FRONT DRAPED ACROSS W LAKE SUPERIOR AND IWD.
BY 18Z IT WILL LIKELY STRETCH ACROSS ALGER AND MENOMINEE
COUNTIES...BEFORE EXITING EAST BY 00Z. THE MAIN STORY WILL BE THE
WIND SHIFT AND CLOUD COVER...WITH MUCH OF THE COLD AIR WAITING FOR A
UNTIL THE WINDS BECOME MORE NORTHERLY DURING THE LATE AFTERNOON
HOURS. IT STILL SHOULD BE ENOUGH TO BRING LES TO THE FAR W...WITH
LIGHT AMOUNTS EXPECTED.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
MONDAY NIGHT INTO TUESDAY NIGHT...THE SURFACE LOW MOVES FROM THE MID
MS VALLEY TOWARD THE SRN GREAT LAKES AS THE MID LEVEL TROUGH SWEEPS
THROUGH THE REGION. MODEL PREFERENCE REMAINS WITH THE MORE CONSISTENT
12Z/00Z ECMWF SUPPORTED BY THE UKMET WHICH BRING THE SFC LOW NEAR
CHICAGO BY 12Z/TUE AND TO DTW BY 18Z/TUE. THE GEM REMAINED STRONGER
AND FARTHER NORTH WHILE THE GFS WAS FARTHER SOUTH. MODERATE 700-300
QVECTOR CONV ASSOCIATED WITH THE MID LEVEL TROUGH AND UPPER LEVEL DIV
WITH THE RIGHT ENTRANCE OF THE UPPER LEVEL JET OVER ONTARIO WILL
SUPPORT AN EXPANDING AREA OF LIGHT SNOW ACROSS WI INTO UPPER MI LATE
MON NIGHT INTO TUE MORNING. INCREASING NRLY WINDS WITH 850 MB TEMPS
DROPPING TO -15C BY 12Z/TUE AND TO NEAR -18C BY 18Z/TUE WILL LEAD TO
LAKE ENHANCED SNOW FOR NORTH WIND SNOWBELTS. NAM COBB SNOW/WATER
RATIO OUTPUT SUGGESTS THAT THE HIGHER SNOW/WATER RATIOS ARE MORE
LIKELY OVER THE WEST...WHERE THE COLD AIR ARRIVES EARLIER. SNOWFALL
TOTAL GENERALLY IN THE ADVY CATEGORY ARE EXPECTED WITH 18 HOUR
AMOUNTS IN THE 4 TO 7 INCH RANGE. SNOW AMOUNTS OF AN INCH OR TWO AT
MOST ARE EXPECTED AWAY FROM LAKE SUPERIOR.
THE SNOWFALL IS EXPECTED TO DIMINISH FROM WEST TO EAST TUESDAY
AFTERNOON AS THE DEEPER MOISTURE DEPARTS AND SUBSIDENCE ACYC FLOW
BUILD INTO THE AREA. WINDS GRADUALLY BACK MORE TO THE WNW ON TUES
NIGHT AS SFC RIDGE APPROACHES THE AREA. LES INTENSITY WILL CONTINUE
TO DIMINISH BUT WITH AMPLE INSTABILITY (850 MB TEMPS STILL AROUND
-19C). SO WITH SNOWBAND POSITIONS SHIFTING OVERNIGHT...ADDITIONAL
ACCUMULATIONS WILL BE LIGHTER...GENERALLY IN THE 1 TO 3 INCH RANGE.
WEDNESDAY INTO THU...THE GFS WAS FASTER AND FARTHER SOUTH WITH THE
NEXT SHORTWAVE TROUGH IN QUICK WNW FLOW PATTERN. GIVEN LIMITED
CONFIDENCE WITH FCST DETAILS...ONLY CHANCE POPS FOR SYNOPTIC SCALE
SNOW WERE INCLUDED. NW FLOW LES WILL AGAIN DEVELOP IN THE WAKE OF
THE LOW FROM LATE WED NIGHT INTO THU AS 850 MB TEMPS FALL INTO THE
-20C TO -25C RANGE.
THU NIGHT INTO FRI...AFTER A TRANSIENT RIDGE MOVES THROUGH THU
NIGHT...MODELS SUGGEST THAT A WAA PATTERN AHEAD OF THE NEXT
SHORTWAVE AND SFC TROUGH COULD BRING LIGHT SNOW TO THE AREA FRI.
SAT INTO SUN...ECMWF/GFS AND ASSOCIATED ENSEMBLES SHOW TRANSITION
TOWARD A MILDER PATTERN WITH A RETURN TO MUCH ABOVE NORMAL
TEMPERATURES BY SUN AND INTO NEXT WEEK. THERE MAY BE SOME LIGHT PCPN AS
A WARM FRONT MOVES INTO THE AREA...BUT ANY PCPN WOULD LIKELY BE
LIGHT.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
THE CLEARING LINE OF LOW END MVFR CEILINGS IS SET UP ACROSS NORTHERN
WI AND SLIDING INTO IWD...MOVING NE AROUND 20KTS. AT THIS POINT THAT
WOULD RESULT IN THE CLEARING LINE OVER CMX AND SAW AROUND 20-21Z.
THIS WILL BE AROUND THE SAME TIME WHEN STRONGER WINDS BEGIN TO SLIDE
IN ALOFT...AROUND 2-4KFT MAXING OUT AROUND 45-55KTS BETWEEN 01-05Z
MONDAY. ALONG WITH STRONG WINDS /GUSTING INTO THE 22-30KT RANGE AT
THE SFC/ THERE WILL ALSO BE A VERY SMALL CHANCE OF FREEZING DRIZZLE
AS ANOTHER ROUND OF CLOUDS SLIDE IN AFTER 00Z. WILL KEEP IT OUT OF
THE FCST AT THIS TIME DUE TO THE LIMITED POTENTIAL /WITH THE BEST
CHANCE BEING WELL INLAND OF W LAKE SUPERIOR/. WILL STILL PLAY UP
ADDITIONAL LOW LEVEL MOISTURE AT ALL LOCATIONS...WITH SNOW SHOWERS
AROUND DAY BREAK AS FAVORABLE W WINDS BECOME MORE NW AT CMX AND IWD.
&&
.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/...
BETWEEN THE EXITING HIGH TO OUR SE...AND NEARING LOW TO THE
WEST...STRENGTHENING SW FLOW WITH GALES OF 35 TO 40KTS WILL BE
POSSIBLE LATE THIS AFTERNOON THROUGH THE OVERNIGHT HOURS /STRONGEST
OVER THE EASTERN HALF OF LS/. LOW PRESSURE ACROSS SOUTHEASTERN
MANITOBA WILL SHIFT TO CENTRAL ONTARIO BY DAYBREAK MONDAY...AND EXIT
TO WESTERN QUEBEC WHILE DRAGGING A TROUGH ACROSS LS DURING
THE DAY MONDAY. AN ADDITIONAL LOW WILL RIDE ALONG THE TROUGH...FROM
THE MID MISSISSIPPI VALLEY TO THE LOWER GREAT LAKES MONDAY NIGHT
INTO TUESDAY MORNING...BEFORE EJECTING TO THE NEW ENGLAND STATES
TUESDAY EVENING. EXPECT A 30.2 INCH RIDGE TO BUILD ACROSS LS TUESDAY
NIGHT INTO WEDNESDAY. LOW PRESSURE OVER THE DAKOTAS WEDNESDAY
MORNING WILL DEEPEN ACROSS THE UPPER GREAT LAKES WEDNESDAY NIGHT.
THE LOW WILL THE SHIFT TO WESTERN QUEBEC THURSDAY EVENING...WHILE
HIGH PRESSURE SINKS ACROSS THE UPPER GREAT LAKES. THE HIGH PRESSURE
SYSTEM WILL THEN FILL FRIDAY AFTERNOON OVER THE LOWER GREAT
LAKES...WHILE ANOTHER LOW NEARS FROM THE WEST.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 AM EST MONDAY FOR LSZ266-267.
GALE WARNING UNTIL 1 AM EST MONDAY FOR LSZ244-245-265.
GALE WARNING UNTIL 7 AM EST MONDAY FOR LSZ263-264.
LAKE MICHIGAN...
GALE WARNING UNTIL 7 AM EST MONDAY FOR LMZ248-250.
&&
$$
SHORT TERM...KF
LONG TERM...JLB
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1156 AM CST SUN JAN 15 2012
.AVIATION...
VFR FLIGHT RULES TO PREVAIL THROUGH THIS EVENING...WITH WESTERLY
WIND SPEEDS BECOMING GUSTY AT TIMES THIS AFTERNOON. STRONG MIXING
SHOULD ALLOW THE TRANSFER OF MOMENTUM ALOFT TO THE SURFACE...WHICH
WOULD SUGGEST WIND GUSTS OF UP TO 20KTS ACROSS NORTHWEST NEBRASKA.
ELSEWHERE 15 KTS SEEMS REASONABLE. AN ARCTIC FRONT WILL CROSS THE
REGION LATER THIS EVENING...BRINGING A WIND SHIFT AND POSSIBLY -SN
MID DAY TOMORROW. HAVE THE FRONTAL PASSAGE NEAR THE VTN TERMINAL
AROUND 00Z MONDAY...AND THROUGH LBF BY 03Z. WIND GUSTS FROM THE
NORTH NORTHWEST OF UP TO 17KTS WILL OCCUR ALONG AND BEHIND THE
FRONTAL PASSAGE.
&&
.PREV DISCUSSION... /ISSUED 712 AM CST SUN JAN 15 2012/
UPDATE...
SHORT TERM...
A LOOK AT THE MORNING UA FLIGHTS FROM LBF...UNR AND DNR AS WELL AS
THE RUC...GEM REG AND HRRR FORECAST TEMPS SUGGESTED RAISING 1ST
PERIOD MAX TEMPS A FEW DEGREES. WITH DEEPER VERTICAL MIXING TO
850 MB THESE TEMPS SHOULD BE REACHABLE AND STRONGER WINDS NEAR THE
BREEZY CATEGORY SHOULD DEVELOP AS WINDS AT H850 ARE FCST TO REACH 30
TO 35 KTS.
THE HRRR SUGGESTED RED FLAG CONDITIONS BUT A BLEND OF HRRR AND
DRIER MAV GUIDANCE USING THE WARMER HIGHS ONLY PRODUCED RH NEAR 20
PERCENT SO THE UPDATED FCST DOES NOT INCLUDE A RED FLAG WARNING.
PREV DISCUSSION... /ISSUED 400 AM CST SUN JAN 15 2012/
SHORT TERM...TODAY THROUGH TUESDAY NIGHT
FORECAST CONCERNS THROUGH THIS PERIOD DEAL WITH SNOW CHANCES
MONDAY AND MONDAY NIGHT AS WELL AS TEMPERATURES THROUGHOUT THE PERIOD.
AT 08Z WATER VAPOR IMAGERY SHOWED RIDGING OVER THE CENTRAL AND
NORTHERN PLAINS AS A SHORTWAVE TROUGH MOVED INTO THE PACIFIC
NORTHWEST WITH AN ENHANCED BIT OF ENERGY PLACED OVER SOUTHERN SASKATCHEWAN.
MEANWHILE ANOTHER CIRCULATION WAS OBSERVED OFF THE CALIFORNIA
COAST IN THE SOUTHERN STREAM. CLOSER TO HOME...THERE WERE A FEW
CLOUDS SEEN OVER THE FORECAST AREA EARLY THIS MORNING MOVING OVER
THE RIDGE...AND WITH WARM AIR PUSHING IN...TEMPERATURES STAYED
MILD FOR THIS TIME OF YEAR. AT 08Z...OBSERVATIONS INDICATED MID
20S TO LOW 30S ACROSS MUCH OF NEBRASKA. PLENTIFUL WARM AIR
ADVECTION HAS BEEN TAKING PLACE OVERNIGHT AS COMPARING LAPS
SOUNDINGS TO THE KLBF SOUNDING FROM 15.00Z WOULD SHOW AN INCREASE
IN TEMPERATURES BETWEEN 800 TO 850MB OF AROUND 9 DEGREES FROM 00Z
TO 07Z.
BUFKIT FORECAST SOUNDINGS FROM BOTH THE NAM/GFS ARE NOT HANDLING THE
WARM AIR PATTERN FOR TODAY WELL AS THEY FAILED TO MIX OUT THE
BOUNDARY LAYER THIS AFTERNOON. THIS HAS BEEN A PROBLEM IN THE PAST
WHICH HAS FORECASTED TEMPERATURES MUCH TOO COLD...SO DID NOT LOOK AT
THESE MODELS FOR TEMPERATURES TODAY. FROM THE FORECAST SOUNDINGS
ASSUMING MIXING TO 850 OR 875MB WOULD BRING TEMPERATURES THIS
AFTERNOON INTO THE 60S ACROSS MUCH OF SOUTHWEST INTO CENTRAL
NEBRASKA. THESE NUMBERS WILL BE WELL ABOVE NORMAL...BUT DON/T
EXPECT TO REACH RECORD NUMBERS TODAY. CONFIDENCE ROSE IN THAT LAST
STATEMENT AS STANDARDIZED ANOMALY DATA SHOWED 850MB TEMPERATURES
AT 1.5 STANDARD DEVIATIONS ABOVE NORMAL. WOULD LIKE THAT TO BE
HIGHER IF FORECASTING RECORD NUMBERS. WINDS AT THE TOP OF THE
MIXED LAYER WILL ONLY BE 15 TO 20KTS SO DON/T EXPECT WINDS TO BE
TOO STRONG TODAY. THIS IS A POSITIVE IN TERMS OF FIRE WEATHER
CONCERNS AS RELATIVE HUMIDITY WILL BE LOW TODAY. SEE FIRE WEATHER
DISCUSSION BELOW FOR MORE DETAILS.
AS TODAY PROGRESSES...THE SHORTWAVE TROUGH OVER THE PACIFIC
NORTHWEST WILL MOVE EAST TOWARDS THE NORTHERN ROCKIES WITH THEA
SHORTWAVE TROUGH OVER SASKATCHEWAN WILL MOVE EAST ACROSS SOUTHERN
CANADA. THIS WILL LEAD TO A SURFACE FRONT CENTERED OVER SOUTHERN
CANADA TO ALSO MOVE EAST...DRAGGING ALONG A COLD FRONT ACROSS THE
PLAINS. THE TIMING OF THE FRONT WILL BE TO MOVE INTO NORTHWEST
NEBRASKA LATER THIS AFTERNOON...SO HIGH TEMPERATURES SHOULD SEE
LITTLE AFFECT FROM COLDER AIR COMING SOUTH.
TEMPERATURES TONIGHT WILL DROP SIGNIFICANTLY AS HIGH PRESSURE
BUILDS IN FROM THE NORTH TO WEAKEN THE WINDS AND PUSH ANY CLOUDS
OUT OF THE AREA /ESPECIALLY OVER THE PANHANDLE/. ONGOING FORECAST
IS A BIT WARMER THAN SOME STATISTICAL GUIDANCE...WITH THE
UNCERTAINTY IN THE DROP OFF OF WINDS TO IMPACT THE FORECAST LOWS.
THE MAIN PACIFIC NORTHWEST SHORTWAVE WILL PASS ACROSS THE ROCKY
MOUNTAINS BY MONDAY MORNING AND INTO THE NORTHERN AND CENTRAL
PLAINS THROUGH THE DAY MONDAY. THIS SYSTEM WILL BRING SNOW CHANCES
TO THE FORECAST AREA FOR MONDAY AND MONDAY NIGHT. DID BACK OFF A
BIT ON SNOW CHANCES MONDAY MORNING AS A SUBSTANTIAL DRY LAYER
LOOKS TO BE IN PLACE ACCORDING TO CROSS SECTIONS AND FORECAST
SOUNDINGS TO SLOW THE ONSET OF PRECIPITATION AS THE COLUMN
SATURATES. HIGHEST CHANCES ARE GOING TO COME AFTER 18Z MONDAY
THROUGH 17.06Z AS THE COLUMN IS SATURATED AND COMBINES WITH THE
STRONGEST UPPER LEVEL DYNAMICS AS WELL A FRONTOGENESIS SIGNAL IN
THE 700 TO 600MB LAYER. THE SYSTEM AS A WHOLE WILL HAVE QUITE A
BIT OF MOISTURE WITH IT...BUT A GREAT DEAL OF THAT MOISTURE WILL
BE SQUEEZED OUT AS IT OVERPASSES THE MOUNTAINS. THUS ONLY LOOKING
FOR LIGHT SNOW AMOUNTS FOR MONDAY AND MONDAY NIGHT. AS MUCH COOLER
AIR WILL BE IN PLACE ALOFT...HIGHS MONDAY WILL BE SOME 30 DEGREES
COOLER THAN WHAT OCCURRED SUNDAY. MONDAY NIGHT IS LOOKING TO BE
THE COLDEST NIGHT OF THE WEEK AS 850MB TEMPERATURES DROP TO 12 TO
15 DEGREES BELOW ZERO. THERE DOES REMAIN SOME UNCERTAINTY TO HOW
FAR TO DROP LOWS THIS PERIOD AS CLOUDS MAY REMAIN DUE TO A
DEPARTING SHORTWAVE TROUGH AND WINDS ACROSS CENTRAL NEBRASKA STAY
BREEZY. LOCATIONS OVER THE PANHANDLE SHOULD SEE THE COLDEST
TEMPERATURES AS SKIES CLEAR AND WINDS DECREASE.
TEMPERATURES ARE FORECAST TO BE NEAR NORMAL FOR TUESDAY ALTHOUGH
WARM AID ADVECTION WILL START UP AGAIN DURING THE DAY. THIS REALLY
DOESN/T KICK IN UNTIL LATER IN THE DAY SO WON/T BE TOO QUICK TO
RAISE HIGHS.
LONG TERM...WEDNESDAY THROUGH SATURDAY
THIS PERIOD OF THE FORECAST CONTINUES TO SEE MUCH UNCERTAINTY AS
IT RELIES HEAVILY ON THE PLACEMENT OF A SURFACE FRONTAL BOUNDARY
TO DELINEATE WHERE THE MUCH COLDER TEMPERATURES WILL BE IN PLACE
WHILE LOCATIONS TO THE SOUTH OF THE FRONT WILL SEE CONDITIONS STAY
ABOVE NORMAL. ALTHOUGH THERE ARE DIFFERENCES BETWEEN MODEL
SOLUTIONS...THE MAIN CONSENSUS IS TO KEEP THE COLDER (-20C OR
COLDER AIR AT 850MB OVER THE DAKOTAS AND WELL NORTH OF THE
FORECAST AREA. THERE WILL BE A TIGHT TEMPERATURE GRADIENT SO AS
THIS AIR MAY COME INTO NORTHERN NEBRASKA...MAY SEE A TEMPERATURE
RANGE ACROSS THE FORECAST AREA FROM THE MID 20S TO THE MID 50S.
THE FLOW THROUGH THIS TIME WILL BE QUICK NORTHWEST FLOW AND THERE
DOES LOOK TO BE POTENTIAL FOR A QUICK SHOT OF PRECIPITATION
THURSDAY NIGHT. KEPT THE MENTION OF THIS TO THE FAR NORTHEAST
PORTIONS OF THE FORECAST AREA AS THERE IS LOW CONFIDENCE BUT HARD
TO PULL CHANCES WITH SEVERAL MODEL SOLUTIONS PUSHING A TROUGH
ACROSS THE AREA.
FIRE WEATHER...
ALTHOUGH DEWPOINTS ARE FORECAST TO SLOWLY RISE THROUGH THE
DAY...THE COMBINATION WITH THE ABNORMAL WARM TEMPERATURES WILL
DROP RELATIVE HUMIDITY DOWN TO 15 TO 25 PERCENT ACROSS MUCH OF
WESTERN AND NORTH CENTRAL NEBRASKA. FUELS CONTINUE TO BE PRIMED
FOR BURNING DUE TO THE LACK OF PRECIPITATION OVER THE LAST SEVERAL
WEEKS SO THOSE WITH FIRE CONCERNS ARE URGED TO PAY CLOSE ATTENTION
TO CURRENT CONDITIONS AT YOUR SITE. WINDS LOOK TO STAY BELOW RED
FLAG WARNING CRITERIA SO WILL TO EXPECT NEAR CRITICAL CONDITIONS
FOR FIRE WEATHER. ALSO...EVEN IF A SITE OR TWO DOES HIT RED FLAG
CRITERIA...DON/T EXPECT IT TO LAST 3 HOURS OR MORE SO WILL STICK
WITH NO HAZARD PRODUCT FOR FIRE WEATHER CONCERNS TODAY.
HYDROLOGY...
ICE JAM PROBLEMS CONTINUE ALONG THE NORTH PLATTE RIVER BETWEEN
LEWELLEN AND LAKE MCCONAUGHY. THE WARM TEMPERATURES TODAY MAY HELP
TO BREAK UP SOME OF THE ICE AND ALLEVIATE THE FLOODING...HOWEVER
THE COLD /BELOW FREEZING/ TEMPERATURES FORECAST FOR THE FIRST FEW
DAYS OF THE WORK WEEK WILL LIKELY CAUSE MORE BUILDUP OF ICE TO
PROLONG THE ICE JAM FLOODING IN THIS AREA. IN ADDITION...OTHER
AREAS ALONG THE NORTH PLATTE RIVER MAY SEE ICE JAMMING OCCUR THIS
WEEK.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM/EXTENDED...BROOKS
AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS SPOKANE WA
246 PM PST Sun Jan 15 2012
.SYNOPSIS...A cold and unstable air mass over the area will allow
for snow showers for most locations. accumulations will generally
be light...however moderate snow amounts are possible...over the
Idaho Panhandle...Blue Mountains and near the Cascade Crest. A
stronger system will arrive between Tuesday night and Wednesday.
This system will bring heavy snow to portions of the Inland
Northwest...however its precise location remains questionable at
this time.
&&
.DISCUSSION...
Tonight and Monday...Very cold and unstable upper level low will
provide the weather focus during this period. 500 mb temperatures
have fallen below -40C over the entire forecast area this
afternoon...however most of the convection thus far has occurred
in a sw-ne band of potential instability extending from the Blue
Mountains to the central Idaho Panhandle. This pattern will change
somewhat overnight as the focus shifts toward the incoming
shortwave trough centered just northeast of Portland as of 2pm. As
of 1pm...the NAM and RUC positioned this feature quite well and
both move it into the Cascades around 00z and into the SE corner
of Washington by 12z Monday morning. Although most of the snow
showers will concentrate near this feature...we cannot entirely
rule out additional showers elsewhere across the forecast area
tonight as the atmosphere will remain quite unstable with lifted
index values holding near 0...at least over the eastern third of
Washington and most of the Idaho Panhandle. Snowfall amounts will
be tricky. The heaviest amounts will generally fall near and just
northeast of the surface low track but this is where the models
diverge significantly. The 18z NAM wants to place a secondary
surface low well north of the upper level shortwave
trof...somewhere over southern Spokane County by 12z with a weaker
low near Lewiston. This does not make a whole lot of sense
considering the upper level forcing and lack of a low-level
thermal gradient. If the NAM were to verify...we`d be looking at
some 1-3" snowfall amounts from roughly Sprague to Harrison
through mid-morning. We will lean toward the more consistent
GFS/RUC and SREF solutions which keep the low much further south
and place the threat of moderate precipitation extending from the
Blue Mountains to the central Idaho Panhandle. Snowfall amounts
will generally range from 1-3" in much of this area...and support
the current batch of snow advisories for the Palouse...Camas
Prairie...and central Panhandle. The Lewiston area should also see
snow...but based on 1-2" amounts mainly falling overnight...it was
not worth expanding the advisories. Its worth noting...that while
these amounts should represent the average accumulations...given
the deep instability and lifting through the dendritic
layer...there will likely be localized amounts which are
considerably heavier. The would be better addressed via short-term
forecasts as it tough to forecast where showers will train over
any given area. The threat of snow showers will begin to wane by
late morning/early afternoon...as the air mass begins to stabilize
ahead of the next system forecast to move into the Cascades late
in the day. fx
Monday night through Wednesday night...The significant longwave
pattern change continues to influence this time interval producing
a substantial amount of precipitation, including heavy snowfall
for many locations including lowlands on Wednesday that changes
over to a wintry mix including some intervals of freezing rain
Wednesday night. All this occurs as a the very cold air mass
lingering over Eastern Washington and Northern Idaho is overrun
with a wet warm front with a well maintained tap into moderate
subtropical moisture. Before this potentially big snowfall events
unfolds the air mass remains cold and conditionally unstable and
the Jet stream/storm track placement is oriented in such a way as
to allow for nuisance mesoscale shortwave migration through it to
produce snow showers of varying areal coverage and intensity
Monday night into Tuesday. Tuesday night before the potentially
big Wednesday snowfall begins a stalled arctic air boundary
lingering just to the north of the Canadian Border that extends
down into portions of Northern Montana remains in place and allows
for deformation/squeezing between the it and the incoming wet warm
frontal zone so a a gradual transition to increased pops for
stratiform snowfall remain a valid segue for Tuesday night.
General low pressure/trof aloft with cold air remaining in place
at lower levels for most of this interval allow for forecast
temperatures to remain on the cool side of what would be
considered normal for this time of year. As far as snow
accumulation totals for Wednesday into Wednesday night...model
runs continue to suggest the potential remains for somewhere on
the order of near a foot of snow accumulation in most lowland
and valley locations with two or more feet in the mountains.
Winter storm watches issued to highlight this are listed at the
bottom of this discussion. /Pelatti
Wednesday night through Sunday...Yet another moisture-laden system
looks to take aim at the area by Thursday. Between that system and
the system Wednesday, the period of calmer weather may be
exceedingly brief. However, given model timing problems and
problems with placement and cold air entrenchment on all models,
the forecast represents a compromise of the ECMWF and GEFS mean
solutions. Both of these are substantially colder then the
operational 12z GFS, however both have exceedingly better
continuity than the GFS.
In attempting to follow some sort of blended solution, thermal
profiles ended up much colder than the GFS and favor a decaying
and retreating frontal boundary draped across the heart of the
CWA. This front will likely become a focusing mechanism for heavy
precipitation by the time Thursday rolls around. Profiles north
of the front will likely favor all snow, while along and south a
transition to either freezing rain or rain seems likely. This was
difficult to pin down given the lack of reliable soundings to look
at, however layer temperatures do suggest an elevated warm layer,
so at least the potential of freezing rain in the transition is
there from Wednesday night into Thursday. Additionally, QPF values
look even higher on Thursday at this point than they do on
Wednesday. This could mean another impressive snowfall where
precipitation remains all snow. At this time, the best estimate on
the rain/snow line will generally be just south of I-90. This
could put Spokane/Coeur D`Alene in a heavy/wet swath of snow yet
again. ECMWF and Canadian QPF suggests the heaviest QPF axis
should roughly run down I-90, with up to 0.75" during the day on
Thursday. Given the warmer profile relative to Wednesday, snow to
liquid ratios are unlikely to be impressive, however if it should
remain all snow during they day, yet another heavy snowfall is
quite possible.
By Thursday night, warmer air continues its northward advance as
Thursday`s system departs to the east. Showery and warmer
conditions persist through Friday night with almost all valley
locations seeing snow levels rise high enough to change to all
rain. This is supported by multiple models pushing 850 mb
temperatures up toward +3 to +4C for a time. By Saturday and
Saturday night, cold air again filters into the region with
unstable snow showers likely becoming the ruler of the region by
the weekend. /Fries
&&
.AVIATION...
18Z TAFS: The two trouble spots through most of this forecast will
be KLWS and KPUW as these two areas will remain subject to the
best chance of -shsn and ocnl MVFR cigs and vsbys through the pd.
Not too confident that many showers will hit either airport
through the day...but aft 04z or so things should pick up and IFR
conditions are a good bet as the upper level low near the area. As
the low tracks into SE WA later tonight...conditions could also
deteriorate aft 06z at KGEG KSFF and KCOE...however the chances are
not as good as KPUW and KLWS. I did place as the IFR/MVFR cigs and
vsbys as the prevailing conditions but may need to back off if low
continues to drop any further southeast. The NAM would say stay
the course...however the GFS and now the HRRR are suggesting
to trend to better conditions. The low will pass over KMWH and
KEAT with a few -shsn but conditions should generally remain in
the VFR category. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 16 28 21 31 18 29 / 30 20 50 40 100 100
Coeur d`Alene 17 29 20 30 17 29 / 40 30 60 60 100 100
Pullman 20 29 24 31 25 35 / 70 70 60 60 100 100
Lewiston 24 34 26 36 28 39 / 70 70 40 50 100 100
Colville 13 28 18 30 11 26 / 20 20 60 60 70 90
Sandpoint 17 29 21 29 12 26 / 60 60 90 90 70 100
Kellogg 18 24 18 27 21 30 / 90 90 90 90 100 100
Moses Lake 13 32 15 35 20 28 / 30 20 20 20 90 100
Wenatchee 14 28 19 31 18 26 / 40 20 20 20 80 100
Omak 2 21 12 28 10 22 / 20 20 30 30 80 80
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Watch from Tuesday evening through Wednesday
evening for Central Panhandle Mountains-Coeur d`Alene Area-
Idaho Palouse-Lewis and Southern Nez Perce Counties-
Lewiston Area-Northern Panhandle.
Winter Weather Advisory until 10 AM PST Monday for Idaho Palouse-
Lewis and Southern Nez Perce Counties.
Winter Weather Advisory until 1 PM PST Monday for Central
Panhandle Mountains.
WA...Winter Storm Watch from Tuesday evening through Wednesday
evening for Lower Garfield and Asotin Counties-Moses Lake
Area-Northeast Blue Mountains-Northeast Mountains-Okanogan
Highlands-Okanogan Valley-Spokane Area-Upper Columbia Basin-
Washington Palouse-Waterville Plateau-Wenatchee Area.
Winter Weather Advisory until 10 AM PST Monday for Washington
Palouse.
Winter Storm Watch from late Monday night through Wednesday
evening for East Slopes Northern Cascades.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1149 AM PST Sun Jan 15 2012
.SYNOPSIS...A cold upper level low will park over the Pacific
Northwest for the next several days. Unstable air associated with
this low will bring snow showers to most locations. accumulations
will generally be light...however moderate snow amounts are
possible...over the Idaho Panhandle...Blue Mountains and near the
Cascade Crest. A much stronger system will arrive between Tuesday
night and Wednesday. This system will bring heavy snow to portions of
the Inland Northwest...however its precise location remains
questionable at this time.
&&
.DISCUSSION...
rest of today...cold core upper level low will toward the Inland
Northwest through the day. As of 11am...it was located near the
mouth of the Columbia River near Astoria and was drifting slowly
toward the east-southeast. 500 mb temps colder than -40C have
already filtered over most of the forecast area...however thus far
showers have been limited to a small portion of SE Washington and
the central Idaho Panhandle where the potential instability is greatest.
Daytime heating will lead to a small increase in the shower
activity over mountainous locations...however we suspect the
biggest batch of showers will arrive tonight as the core of the
upper level low swings toward the Cascades. Based on the lows
positioning...we have opted to split this afternoons weather
grid...and indicated an increase in the shower chances late in the
day near the Cascades...including the Wenatchee area and
Waterville Plateau. Given the path of the low across the southern
Washington Cascades...it seems plausible that precip chances will
be greater south of Lake Chelan than north.
As for the current batch of snow advisories...things are looking
good for much of the central Idaho Panhandle...as that is where
most of the showers will occur today. On the other hand...the
Palouse is not looking too favorable...at least through today.
Things will pick up later tonight and early Monday as the upper
level low nears...but snow amounts..at least over the Washington Palouse
may range from 1-2". Not terribly impressive...but since it has
been so long since that area has seen that much snow...we will
leave headline as is. fx
&&
.AVIATION...
18Z TAFS: The two trouble spots through most of this forecast will
be KLWS and KPUW as these two areas will remain subject to the
best chance of -shsn and ocnl MVFR cigs and vsbys through the pd.
Not too confident that many showers will hit either airport
through the day...but aft 04z or so things should pick up and IFR
conditions are a good bet as the upper level low near the area. As
the low tracks into SE WA later tonight...conditions could also
deteriorate aft 06z at KGEG KSFF and KCOE...however the chances are
not as good as KPUW and KLWS. I did place as the IFR/MVFR cigs and
vsbys as the prevailing conditions but may need to back off if low
continues to drop any further southeast. The NAM would say stay
the course...however the GFS and now the HRRR are suggesting
to trend to better conditions. The low will pass over KMWH and
KEAT with a few -shsn but conditions should generally remain in
the VFR category. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 29 19 29 21 31 18 / 20 60 60 50 40 100
Coeur d`Alene 31 18 28 20 30 17 / 20 60 70 60 60 100
Pullman 31 20 30 24 31 25 / 60 70 70 60 60 100
Lewiston 37 21 35 26 36 28 / 50 60 50 40 50 100
Colville 28 16 28 18 30 11 / 20 30 50 60 60 80
Sandpoint 30 18 26 21 29 10 / 30 70 70 90 90 80
Kellogg 27 18 25 18 27 21 / 80 90 80 90 90 100
Moses Lake 29 12 32 15 35 17 / 10 20 20 20 20 90
Wenatchee 29 16 28 19 31 17 / 20 20 20 20 20 80
Omak 24 9 26 12 28 10 / 10 20 30 30 30 80
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 1 PM PST Monday for Central
Panhandle Mountains.
Winter Weather Advisory until 10 AM PST Monday for Idaho Palouse-
Lewis and Southern Nez Perce Counties.
WA...Winter Weather Advisory until 10 AM PST Monday for Washington
Palouse.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1158 AM CST SUN JAN 15 2012
.UPDATE...CLOUD DECK STEADILY PUSHING OFF TO THE
NORTHEAST...LEAVING CLEAR SKIES IN ITS WAKE...EXCEPT FOR A FEW
CIRRUS. DECK SHOULD CLEAR NORTHEAST CORNER OF CWA BY 19Z. RUC LOW
LEVEL MOISTURE FIELDS SHOW DRIER AIR ADVECTING IN ON SOUTHERLY
FLOW SO EXPECTING FULL SUNSHINE FOR THE AFTERNOON. ON ACCOUNT OF
THE QUICKER DEPARTURE OF THE CLOUD DECK...RAISED HIGHS A TAD.
&&
.AVIATION/18Z TAFS/...A MIX OF LOW AND MID LEVEL CLOUDS LINGER
NORTHEAST OF MADISON THIS MORNING...WITH CLEARING CONTINUING TO
PUSH IN FROM THE SOUTHWEST. OTHER THAN A FEW SPOTS OF BRIEF MVFR IN THE
NORTHEAST...SHOULD SEE VFR CONDITIONS THROUGH THE REMAINDER OF
THE DAY.
MODELS CONTINUE TO SATURATE THE LOW LEVELS TONIGHT AHEAD OF AN
APPROACHING COLD FRONT. THINK STRATUS WILL DEVELOP LATE
EVENING/EARLY NIGHT...WITH CIGS POSSIBLY AS LOW AS IFR BY MORNING.
KEPT OUT MENTION OF FREEZING DRIZZLE IN THE TAFS AS PROBABILITY IS
ON THE LOW SIDE WITH THE MOISTURE EXPECTED TO BE QUITE SHALLOW.
IF THINGS SATURATE A BIT DEEPER THAN EXPECTED...MAY NEED TO
CONSIDER ADDING FOR LATE EVENING AND OVERNIGHT.
LOW CLOUDS EXPECTED TO LINGER THROUGH THE DAY MONDAY...ESPECIALLY
FROM AROUND MADISON AND EASTWARD.
&&
.PREV DISCUSSION... /ISSUED 330 AM CST SUN JAN 15 2012/
TODAY AND TONIGHT...FORECAST CONFIDENCE...MEDIUM.
EXPECT AREA OF LOW STRATUS OVER SOUTHERN WISCONSIN TO GRADUALLY
ERODE AND PUSH TO THE EAST TODAY AS SOUTH WINDS
INCREASE...WEAKENING INVERSION...HOWEVER CLOUDS WL PROBABLY HANG
ON THROUGH THE MRNG IN THE EAST. STRONG LOW LEVEL WARM AIR
ADVECTION WL LIKELY BRING MORE MID/HIGH OVER THE AREA THRU THE
DAY. SHORT TERM GUIDANCE IN GOOD AGREEMENT ON CARRYING
INTENSIFYING LOW PRESSURE OVER SRN CANADA NEXT 24 HOURS. WHILE MID
LAYERS EXPECTED TO REMAIN DRY...INCREASING SOUTH WINDS WL PULL
DEEPER LOW LEVEL MOISTURE BELOW 4K FEET NORTHWARD INTO SRN WI.
THIS DEEPER MOISTURE WILL INTERACT WITH INCREASING LOW LEVEL
CONVERGENCE ALONG APPROACHING SURFACE COLD FRONT TO RESULT IN MORE
STRATUS DEVELOPING OVERNIGHT TNGT. ENOUGH LOW LEVEL CONVERGENCE
AND SHEAR AT THE TOP OF THE CLOUD LAYER TO POSSIBLY SHAKE OUT SOME
LIGHT FREEZING DRIZZLE TONIGHT. BESIDES INCREASING LOW LEVEL
RH...00Z 4KM WRF ALSO SHOWS SUBSTANTIAL INCREASE IN TOTAL COLUMN
CONDENSATE OVERNIGHT. NAM 280 THETA SFC SHOWS CONDENSATION
PRESSURE DEFICITS DECREASE TO LESS THAN 10MB OVER NORTHWEST CWA
WITH 2 TO 5 MICROBARS OF ISENTROPIC OMEGA. HENCE WL GO WITH A SCHC
FOR -ZR IN THE NORTHWEST WITH -ZL ELSEWHERE.
SHORT TERM...MONDAY THROUGH TUESDAY NIGHT...FORECAST CONFIDENCE
MEDIUM.
COLD FRONT MOVES SOUTHEAST THROUGH THE AREA ON MONDAY. AHEAD OF
THE FRONT...AREA FORECAST SOUNDINGS FROM NAM...AND TO A LESSER
EXTENT THE GFS...SHOW MOIST LOW LEVEL AIRMASS BELOW INVERSION. TOP
DOWN FLOWCHART YIELDS FREEZING DRIZZLE POTENTIAL IN THE
MORNING...WITH SURFACE TEMPERATURES STILL AT OR BELOW FREEZING.
FOR NOW...ONLY MENTIONED PATCHY LIGHT FREEZING DRIZZLE AND AREAS
OF FOG IN THE FAR SOUTHEAST AND FAR SOUTH MONDAY MORNING SOUTHEAST
OF THE FRONT...WHERE BEST SHOT AT THESE CONDITIONS EXIST. MAY HAVE
TO BE EXPANDED NORTHWESTWARD PER NAM FORECAST SOUNDINGS IN FUTURE
FORECASTS.
AREA OF LOW LEVEL FRONTOGENESIS FOCUSES ACROSS NORTHEAST ILLINOIS
LATER ON MONDAY...AS THE COLD FRONT STALLS ACROSS THAT AREA. FAR
SOUTHEAST AND FAR SOUTHERN COUNTIES CLOSE ENOUGH TO THIS AREA TO
KEEP SLIGHT CHANCES FOR LIGHT RAIN/LIGHT SNOW...ALONG WITH AREAS
OF FOG. AIR COLUMN NOT SATURATED THROUGH A DEEP LAYER YET...SO
THIS COULD BE MORE OF A DRIZZLE SITUATION. HIGHS SHOULD REACH THE
MID 30S ACROSS THE AREA.
SHORT TERM MODELS CONTINUE TO TAKE WEAK SURFACE LOW FROM NORTHEAST
MISSOURI TO SOUTHERN LOWER MICHIGAN MONDAY NIGHT...THEN FURTHER
AWAY FROM THE AREA TUESDAY. 850MB TO 700MB FRONTOGENESIS LAYER
MOVES THROUGH THE FAR SOUTHEAST COUNTIES MONDAY NIGHT...WITH THE
MAIN SHORTWAVE TROUGH MOVING THROUGH THE AREA TUESDAY. THIS
FEATURE REMAINS AN OPEN WAVE DURING THIS TIME.
WENT WITH LIKELY POPS FOR LIGHT SNOW IN THE FAR SOUTHEAST MONDAY
NIGHT...WITH LOWER POPS TO THE NORTHWEST. SOME QUESTION AS TO HOW
LONG AIR COLUMN WILL TAKE TO SATURATE DURING THIS TIME...AS
NAM/GFS FORECAST SOUNDINGS SHOWING SOME DRY AIR IN THE 850MB TO
500MB LAYER. TEMPTED TO LOWER POPS MONDAY NIGHT...BUT WILL KEEP
THEM AND SEE IF FUTURE MODEL RUNS CONTINUE TO SHOW DRY AIR IN THE
LOW TO MID LEVELS.
CONTINUED TO MENTION LIKELY POPS FOR LIGHT SNOW TUESDAY. PRESSURE
GRADIENT INCREASES AND ALLOWS FOR GUSTY NORTHWEST WINDS AND COLD
AIR ADVECTION ACROSS THE AREA. COLD AIR ADVECTION SHOULD BRING
SNOW TO LIQUID RATIOS UP INTO THE TEENS TO PERHAPS 20 TO 1 AS THE
DAY GOES ON. HAVE A GENERAL 1.5 TO 2.0 INCHES OF SNOW EXPECTED
ACROSS THE AREA. THIS SHOULD IMPACT THE TUESDAY MORNING COMMUTE.
WILL CONTINUE TO MENTION IN HAZARDOUS WEATHER OUTLOOK FOR NOW.
HIGH PRESSURE RIDGE WILL SHIFT INTO THE AREA TUESDAY
NIGHT...BRINGING A QUICK END TO THE LIGHT SNOW FROM WEST TO EAST
BY EVENING. COLDER TEMPERATURES WILL INVADE THE AREA...AND WITH A
FRESH SNOW COVER SHOULD DROP LOWS TUESDAY NIGHT TO AROUND ZERO OR
JUST BELOW ZERO IN MOST AREAS.
LONG TERM...WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE
MEDIUM.
FAIRLY ACTIVE WEATHER PATTERN CONTINUES THROUGH THIS PERIOD...WITH
SEVERAL SYSTEMS MOVING THROUGH THE REGION. GFS/ECMWF SHOWING
SYSTEM CLIPPING THE AREA WEDNESDAY NIGHT INTO EARLY THURSDAY...SO
KEPT POPS GOING FOR THAT PERIOD. THEY DIFFER QUITE A BIT WITH THE
END OF THE WEEK SYSTEM...SO WENT WITH CONSENSUS POPS AND
TEMPERATURES AFTER THURSDAY.
AVIATION/12Z TAFS/...
MVFR CLOUD SHIELD OVER MOST OF SRN WI LINGERING FROM WEAK LOW
LEVEL FLOW AND MID LEVEL DISTURBANCE WL CONTINUE TO SLOWLY ERODE
FROM THE WEST TODAY AND SLIDE EWD DUE TO INCREASING LOW LEVEL
SOUTH WINDS. STRONG WARM AIR ADVECTION SHOULD STILL BRING A PERIOD
OF MID/HIGH CLOUDS TODAY AFTER LOW CLOUDS THIN. INCREASING SOUTH
WINDS WILL PULL DEEPER LOW LEVEL MOISTURE NORTHWARD DURING THE
DAY. AS IT INTERACTS WITH APPROACHING LOW LEVEL CONVERGENCE ZONE
ASSOCIATED WITH APPROACHING SURFACE FRONT...LOW STRATUS IS
EXPECTED TO DEVELOP OVER THE AREA TONIGHT. ENOUGH LIFT MAY BE
AVAILABLE TO CAUSE SOME PATCHY -ZL OVERNIGHT...WITH THE BEST
CHANCE AT KMSN CLOSER TO BETTER CONVERGENCE. WL INCLUDE WINDSHEAR
REMARK IN 12Z TAFS AS WINDS AT 2K FEET EXPCD TO INCREASE TO 50KTS
TNGT.
MARINE...
A TIGHTENING PRESSURE GRADIENT IS STILL EXPECTED TO DEVELOP OVER
SOUTHERN LAKE MI TODAY AND CONTINUE THROUGH TONIGHT AHEAD OF
STRENGTHENING LOW PRESSURE IN SOUTHERN CANADA. THE RELATIVELY
WARMER WATERS OF LAKE MICHIGAN WILL RESULT IN STEEP LOW LEVEL
LAPSE RATES...WHICH WILL ALLOW STRONGER WINDS TO MIX DOWN TO THE
LAKE SURFACE. FEW GUSTS TO AROUND 33KTS ARE EXPECTED
TONIGHT...ESPECIALLY TOWARD THE OPEN WATER. HENCE WILL LET SMALL
CRAFT ADVY RUN ITS COURSE AND GO INTO EFFECT LATER THIS
MRNG...CONTINUING INTO MONDAY MRNG. WIND SPEEDS WL DIMINISH AS
FRONTAL BOUNDARY SLIDES SOUTHWARD ACROSS THE LAKE ON MONDAY...BUT
SHOULD PICK UP AGAIN AS LOW PRESSURE MOVES ALONG THIS FRONT TO THE
SOUTH OF THE LAKE ON TUE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 9 AM CST MONDAY FOR LMZ643>646.
&&
$$
UPDATE...WIMBERLEY/DDV
TODAY/TONIGHT AND AVIATION/MARINE...MBK
MONDAY THROUGH SATURDAY...WOOD