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Severe Weather Maps, Graphics, and Data Page
Last Update: 17 July 2024 - Change Log
Intro | State Summaries | U.S. Annual Tornado Maps | 2024 Preliminary Reports to Date
Monthly Tornadoes Since 1950 | Bi-monthly Tornadoes by ENSO Phase Strength
Watch Frequency Maps | 20y Annual Average Watches by County | 30-year Severe Climatology
SPC AWIPS Products | Data | Tropical Cyclone Tornadoes | SVR GIS |
This page has charts of the latest preliminary severe storm reports, annual summaries, and links to comma-separated-value (csv) data files from the SPC severe weather database back to 1950.
2023 Total Severe Weather Reports |
![](2023/2023_allsvr.png)
A map of all tornado (red), hail (green), and thunderstorm wind gust (blue) reports from NWS offices in 2023.
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| Monthly Tornadoes by State |
![Maps of Average State Tornadoes per Month](maps.png)
(Click on the maps to go to the maps page.)
| Annual Averages: Tornadoes by State |
| Annual Averages: Tornado Fatalities by State |
| Other U.S. Tornado Summaries |
| Daily Counts and Annual Running Trend (Updated Frequently) |
Mouse over or click for full image --->
Tornado Reports |
Hail Reports |
Wind Reports
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End of year charts for 2023: Tornadoes, Hail, and Wind,
End of year charts for 2022: Tornadoes, Hail, and Wind,
End of year charts for 2021: Tornadoes, Hail, and Wind,
End of year charts for 2020: Tornadoes, Hail, and Wind,
End of year charts for 2019: Tornadoes, Hail, and Wind,
End of year charts for 2018: Tornadoes, Hail, and Wind,
End of year charts for 2017: Tornadoes, Hail, and Wind,
End of year charts for 2016: Tornadoes, Hail, and Wind.
End of year charts for 2015: Tornadoes, Hail, and Wind.
End of year charts for 2014: Tornadoes, Hail, and Wind.
End of year charts for 2013: Tornadoes, Hail, and Wind.
End of year charts for 2012: Tornadoes, Hail, and Wind.
End of year charts for 2011: Tornadoes, Hail, and Wind.
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Mouse over or click for full image --->
Tornado Reports |
Hail Reports |
Wind Reports
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End of year charts for 2023: Tornadoes, Hail, and Wind,
End of year charts for 2022: Tornadoes, Hail, and Wind,
End of year charts for 2021: Tornadoes, Hail, and Wind,
End of year charts for 2020: Tornadoes, Hail, and Wind,
End of year charts for 2019: Tornadoes, Hail, and Wind,
End of year charts for 2018: Tornadoes, Hail, and Wind,
End of year charts for 2017: Tornadoes, Hail, and Wind,
End of year charts for 2016: Tornadoes, Hail, and Wind.
End of year charts for 2015: Tornadoes, Hail, and Wind.
End of year charts for 2014: Tornadoes, Hail, and Wind.
End of year charts for 2013: Tornadoes, Hail, and Wind.
End of year charts for 2012: Tornadoes, Hail, and Wind.
End of year charts for 2011: Tornadoes, Hail, and Wind.
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Plot of the annual running total of tornado reports compared to inflation adjusted values. (Click on graph for a full description.)
End of year chart for 2023
End of year chart for 2022
End of year chart for 2021
End of year chart for 2020
End of year chart for 2019
End of year chart for 2018
End of year chart for 2017
End of year chart for 2016
End of year chart for 2015
End of year chart for 2014
End of year chart for 2013
End of year chart for 2012
End of year chart for 2011
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| ENSO Strength and Bi-monthly U.S. Tornadoes since 1950 (Click link above to go to ENSO page.) |
| 2023 SPC Watch Frequency Maps |
![2023 Watches and Anomalies](2023-wbc-anoms.png)
2023 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
| 2022 SPC Watch Frequency Maps |
![2022 Watches and Anomalies](2022-wbc-anoms.png)
2022 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
| 2015 SPC Watch Frequency Maps |
![2015 Watches and Anomalies](2015-wbc-anoms.png)
2015 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
| 2014 SPC Watch Frequency Maps |
![2014 Watches and Anomalies](2014-wbc-anoms.png)
2014 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
| 2013 SPC Watch Frequency Maps |
![2013 Watches and Anomalies](2013-wbc-anoms.png)
2013 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
| 2012 SPC Watch Frequency Maps |
![2012 Watches and Anomalies](2012-wbc-anoms.png)
2012 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
| 2011 SPC Watch Frequency Maps |
![2011 Watches and Anomalies](2011-wbc-anoms.png)
2011 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
| 2010 SPC Watch Frequency Maps |
![2010 Watches and Anomalies](2010-wbc-anoms.png)
2010 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
| 20y SPC Watch Climatology |
![All Watches](20ywatcha.png)
Average number of severe weather watches per year (2004-2023).
(Click for full-resolution version.)
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![Tornado Watches](20ytora.png)
Average number of tornado watches per year (2004-2023).
(Click for full-resolution version.)
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![Severe Thunderstorm Watches](20ysvra.png)
Average number of severe thunderstorm watches per year (2004-2023).
(Click for full-resolution version.)
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Grab Data: watches_fips_2004-2023.zip |
| 30-year Severe Weather Climatology |
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SPC Tornado and Severe Weather Statistical Products on AWIPS |
Monthly Tornado Statistics are maintained in the AWIPS product STAMTS. Use this product to
find out how many tornadoes have occured so far this year and how
this year compares to past years.
Killer Tornado Statistics are listed in the AWIPS product STATIJ. Use this product for
information about killer tornadoes this year and in the past.
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Severe Weather Database Files (1950-2023) |
The tables below provide the links to comma separated value (.csv) files for tornadoes, hail, and damaging wind, as compiled from NWS Storm Data. Tornado reports exist back to 1950 while hail and damaging wind events date from 1955. The full hail and wind datasets are very large. To facilitate quicker downloads these data have been parsed by decade (1950s through 1990s), and half-decade, or less (from 2000 to the present). Tornado data are provided in raw csv file format below. Actual tornado tracks only (not including individual state segments) are provided in the "Actual_tornadoes.csv" file. Again, please read the format specification for the tornado data.
Please read this document carefully as it describes the format of the .csv files (especially important for tornadoes!). Note 1: The NWS changed criteria for severe hail from 0.75 inch minimum to 1.00 inch minimum in 2010. For legacy purposes, 0.75 inch hail reports will continue to be included in the annual hail csv files. Download the files and sort accordingly if needed. Note 2: See last two pages of the database specification document about the addition of the estimated F-scale column "fc", added to tornado.csv data in 2015.
*** Changes made to the database in 2016 for the 1950-2015 U.S. tornado records ***
Estimated F-scale ratings were calculated for over 1800 tornadoes in the database previously rated with an F-scale entry of -9 (unknown). The scheme used to modify unknown F-scale to estimated F-scale is described in this document:
www.spc.noaa.gov/wcm/OneTor_F-scale-modifications.pdf
For all tornadoes modified in the database, a new information field was added to the database in 2016. The "fc" field (29th column of information in OneTor). "fc" is set to 1 for any tornado with a prior F-scale rating of -9. Thus, it is easy to filter previously unknown ratings, if desired. Please note! Tornadoes were likely underreported prior to 1953. Many tornado statistics are derived from 1953 (or later) to the present. Also, keep in mind that off-CONUS tornadoes are included in the latest version of the 1950-2023 tornado data. These events, while small in total count, include tornadoes in AK, HI, PR, and DC. It is best to filter results carefully when making queries on the tornado database.
It should also be noted that these data are used by the NWS for verification purposes and may not accurately reflect all storm events. Monetary loss information is highly suspect and should be used with caution, if at all. This article provides a good overview about the shortcomings in the NWS severe weather data provided here.
!!! IMPORTANT INFORMATION REGARDING THE SPC SEVERE WEATHER DATABASE !!!
- Read the new change log for latest information/updates.
- Read this paper for a discussion of errors and artifacts in tornado data.
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All torn in one 1.7 mb zip file.
All hail in one 6.8 mb zip file.
All wind in one 9.3 mb zip file.
Map of State FIPS Numbers here.
Text list of County FIPS Numbers here.
Better list of County FIPS Numbers (as xls file) here.
| SPC Tropical Cyclone Tornado (TCTOR) Page |
![Tropical Cyclone Tornadoes](tc_tor.png)
(Click to go to SPC Tropical Cyclone Tornado Page)
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SPC Severe GIS Page |
![Tornado Tracks](tornadoes_population_sm.png)
U.S. map depicting tornado tracks and population density.
(Click to go to SPC Severe GIS Page.)
Note: The content below is updated less frequently.
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Cool Season Watch Days and El Niño Southern Oscillation (ENSO) Phase |
![](2015/mar.png)
With strong El Niño (ENSO warm phase) conditions continuing into the winter months, here's an analysis of how those conditions may influence the number of watch days in December.
The ENSO phase strength was ranked using the Multivariate ENSO Index, or MEI.
The years with the 10 warmest (El Niño) and 10 coldest (La Niña) phases for the December to January time frame, back to 1970, were used to select the total* January watch days within each phase. (*Divide grid cell numbers by 10 to arrive at monthly mean watch days in each phase).
The top map shows the total watch days in the ten Januarys corresponding to the most pronounced El Niño conditions during December-January.
The middle map shows the total watch days for the ten Januarys with most pronounced La Niña conditions during December-January.
The bottom map shows the difference in total watch days between the strongest El Niño months and the strongest La Niña months.
The total watch day summary maps for December, January, February, April, and May also reveal how ENSO phase can influence severe weather potential during the cool season and early warm season.
Lastest information on MEI: //www.esrl.noaa.gov/psd/enso/mei/.
Lastest on ENSO from CPC: //www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/.
| Page Content Archive |
2016
Outlook Forecasts for February 2, 2016
2015
Probability of a Tornado Watch during Week of Christmas
July 17-18, 2015 Radar/Wind Gust Summary
July 17-18, 2015 Radar/Wind Gust Summary
July 12-13, 2015 Radar Composite
A look at May 2015 Watch Anomalies
April 2013, 2014, 2015 Radar-based hail maps
March 2013, 2014, 2015 Radar-based hail maps
No March 2015 Watches through the 23rd
Longest Spans Between Watches
JF Watch Counts 1970-2015
2014
All storm reports across the continental U.S. in 2014
2014 Tornadoes and State Departures through October
Watch counts by month/type (through early September)
Histogram of tornado counts through April 21
Spans without (E)F3-rated tornadoes
A look back at April 3-4, '74 with high resolution model
Analysis of partial season watch counts (pdf)
Midwest Derecho Event(s) of June 30, 2014
ND/MN Derecho of July 21-22, 2014
U.S. Tornado Counts thru May (1953-3014)
Daily Tornado Probability Curve
De-trended U.S. tornado counts through Nov.
2013
2013 Tornadoes by EF-scale Map
Severe Weather Reports Per Year (2003-2012) |
These maps were created by gridding the total number of daily severe weather reports (Midnight to 11:59pm CDT) over the 10-year period from
2003 through 2012 on a 80km grid. The resulting grid numbers are then divided by 10 and smoothed to arrive at the annual average number of
days with a report of severe weather based on official NWS Storm Data records. The 80km grid-point value corresponds to the number of events within
25 miles of a point. While the resulting maps generally match our understanding of severe weather climatology, there are a few exceptions
that come about as a result of how the severe weather event is quantified. Even through the data are smoothed, severe weather reports cluster
around population centers. This can be seen on the "any" or "all" severe weather map in the upper left. Maximum values show up around Charlotte,
NC, Huntsville, AL, Jackson, MS, Springfield, MO, and Dallas, TX. These are locations where more severe weather is reported because more people
live in those areas. The hail reports used to generate the hail frequency map are from reports of hail 1 inch or greater in diameter. Large hail
reports are most common from Rapid City, SD to Denver, CO, Dodge City, KS, and Springfield, MO. The wind report map perhaps poses the greatest
challenge in terms of representing where a greater severe thunderstorm wind threat may exist. The majority of severe thunderstorm wind reports
are verified by falling trees *not* by observed wind gusts of 50 knots or greater. Thus, there is a distinct tendency for severe
thunderstorm winds to be reported in areas with more trees. Recent peer-reviewed studies have compared the severe weather reports used to make
these maps with automated observations (for wind), and radar data (for hail). These studies have found that greater concentrations/frequencies
of severe hail (based on radar) and 50kt or greater severe thunderstorm wind gusts (based on automated observations) are more likely to occur
over parts of the Great Plains and Midwest than what might be indicated in the maps shown here. (Click each map for full resolution version.)
References:
An Objective High-Resolution Hail Climatology of the Contiguous United States
John L. Cintineo, Travis M. Smith, Valliappa Lakshmanan, Harold E. Brooks, Kiel L. Ortega
Weather and Forecasting
Volume 27, Issue 5 (October 2012) pp. 1235-1248
Measured Severe Convective Wind Climatology and Associated Convective Modes of Thunderstorms in the Contiguous United States, 2003-09
Bryan T. Smith, Tomas E. Castellanos, Andrew C. Winters, Corey M. Mead, Andrew R. Dean, Richard L. Thompson
Weather and Forecasting (Also here.)
Volume 28, Issue 1 (February 2013) pp. 229-236
| Annual Tornado Maps (1952-2011) |
![Maps of Annual Tornadoes from 1952 to 2011](annualt.png)
(Click on the maps to go to the Annual Tornado Maps page.)
| U.S. Monthly Tornado Counts, 1950-2010 |
![MoCounts](monthlytorcharts/calendar.png)
Monthly tornado sums (excluding (E)F0 tornadoes) for each month, 1950-2010.
(Click to go to calendar page.)
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