Storm Prediction Center WCM Page
Intro | 2012 U.S. Tornado Summary | State Summaries | U.S. Annual Tornado Maps | 2013 Preliminary Reports to Date
Monthly Tornadoes Since 1950 | Bi-monthly Tornadoes by ENSO Phase Strength
Watch Frequency Maps | 20y Annual Average Watches by County | SPC AWIPS Products | Data | SVR GIS |
| Warning Coordination Meteorologist's Introduction |
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Welcome to the WCM Page for the SPC. 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. As time allows, this page may occasionally serve as a place for preliminary severe weather event assessments.
For additional insight into severe thunderstorms and tornado reports, the SPC and the National Severe Storms Laboratory are collaborating on posting non-operational "feature" content to the U.S. Severe Weather Blog, hosted by NOAA Public Affairs in Norman, Oklahoma.
Check out the annual tornado maps from 1950 through 2009 at the WCM's Annual Tornado Maps page.
Greg Carbin
Warning Coordination Meteorologist
NWS/NCEP Storm Prediction Center
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| January-April US Daily Tornadoes, 1954-2013 |
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With a preliminary count of 87 EF1 and stronger U.S. tornadoes through April 2013, the year is off to a slow start with about half the average number of tornadoes for this period of the year (153 JFMA tornadoes over the past 60 years). If the preliminary count stands, 2013 will rank 49 out of 60 in tornado activity level (through April) since 1954. The most recent year with fewer tornadoes through April occurred in 2005 when 83 EF1 and stronger tornadoes were counted. Through April, 2013 stands in stark contrast to 2011 when a record number of 586 tornadoes (EF1+) were counted through the first four months of the year. Over the last decade, the January through April tornado count has shown dramatic variability. The 2nd least active period on record (52 tornadoes in 2004) and the most active on record (586 in 2011) have occurred during this time. Not including 2013, four of the 10 least active years and four of the 10 most active years, through April, have all occurred since 2002. It is not entirely clear why this variability has appeared in the tornado counts in recent years. However, given this observed variability, simple averages of tornado counts over recent years do not provide much information about expected tornado activity level from any one year to the next.
The image below is from the same data as above only the daily tornadoes are summed through April.
(Click for full resolution images.)
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| Preliminary Annual U.S. Tornado Summary for 2012 |
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| Annual Tornado Maps (1952-2011) |
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(Click on the maps to go to the Annual Tornado Maps page.)
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| Annual Average Number of Tornadoes by State |
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| Annual Average Number of Tornado Deaths by State |
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| Other U.S. Tornado Summaries |
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| U.S. Monthly Tornado Counts, 1950-2010 |
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Monthly tornado sums (excluding (E)F0 tornadoes) for each month, 1950-2010.
(Click to go to calendar page.)
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| Daily Counts and Annual Running Trend (Updated Frequently) |
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ENSO Strength and Bi-monthly U.S. Tornadoes since 1950
(Click link above to go to ENSO page.) |
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| 2012 SPC Watch Frequency Maps |
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2012 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
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| 2011 SPC Watch Frequency Maps |
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2011 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
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| 2010 SPC Watch Frequency Maps |
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2010 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
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| 2009 SPC Watch Frequency Maps |
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2009 Tornado and Severe Watch Count by County and Anomaly
(Click for full-resolution version.)
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| SPC Average Annual Watch Frequency Maps |
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Average number of tornado watches per year (1993-2012).
(Click for full-resolution version.)
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Average number of severe thunderstorm watches per year (1993-2012).
(Click for full-resolution version.)
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| SPC Tornado and Severe Weather Statistical Products on AWIPS |
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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 (1950-2012) |
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The table below provides links to comma separated value (.csv) files for tornado, hail, and damaging wind data as compiled from NWS Storm Data.
Tornado reports exist back to 1950 while hail and damaging wind reports date from 1955. The full datasets are very large, especially hail and wind. To facilitate quicker downloads these data have been parsed by decade (1950s through 1990s), and half-decade, or less (from 2000 to the present).
Please read this document carefully as it describes the format of the .csv files (especially important for tornadoes!). Also note! The NWS changed Severe hail criteria 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 latest hail csv files. Download the files and sort accordingly if needed.
It should further 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.
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All tornadoes in one 5.7mb file. (Same format as above but for 1950-2012.)
Map of State FIPS Numbers here.
Text list of County FIPS Numbers here.
Better list of County FIPS Numbers (as xls file) here.
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| SPC Severe GIS Page |
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U.S. map depicting tornado tracks and population density.
(Click to go to SPC Severe GIS Page.)
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