Weather alerts in the United States
2,728,330 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. Each alert counts once, however many counties it covered.
Weather alerts by state
Each state shaded by its count. Tap a state for its own archive.
- Alerts
- 2,728,330
- Warnings
- 1,305,122
- Watches
- 104,678
- Advisories
- 501,473
- Busiest year
- 2023138,148 alerts
- Average year
- 66,545over 41 years on file
- Busiest day
- April 27, 20111,581 alerts
Over time
By year
Before late 2005 the archive holds only tornado, severe thunderstorm, flash flood and marine warnings, and from 1997 SPC's watches, so the jump that year is the archive widening, not the weather.
By month of the year
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
By state
Every state and territory, with the alerts that covered any part of it. Each state’s page lists every one of them.
- Texas259,482
- Florida166,257
- Kansas113,167
- North Carolina112,357
- Alaska109,098
- Oklahoma107,054
- Georgia106,408
- Virginia93,345
- Alabama88,250
- Missouri83,283
- Nebraska82,614
- Louisiana78,516
- Mississippi77,206
- Arkansas75,556
- California73,956
- New York73,307
- Kentucky72,891
- Illinois71,185
- Colorado70,292
- Ohio68,407
- Pennsylvania65,218
- Tennessee65,000
- Michigan63,881
- Indiana63,042
- South Carolina60,869
- New Mexico59,915
- Minnesota59,620
- Wisconsin54,460
- Iowa53,965
- Montana53,194
- South Dakota48,613
- Arizona46,471
- Wyoming40,515
- West Virginia37,570
- Oregon34,276
- North Dakota31,434
- New Jersey28,825
- Maryland27,605
- Washington25,924
- Idaho25,323
The busiest days
Days with the most alerts issued, by UTC date.
What the archive holds
| Products | From | Source and notes |
|---|---|---|
| Tornado, severe thunderstorm, flash flood and special marine warnings | 1986 | Iowa Environmental Mesonet, reconstructed from the NWS text archive. Issued for whole counties until storm-based polygons, which the archive holds from 2002 and which became the official warning area in October 2007. |
| Tornado and severe thunderstorm watches | 1997 | Storm Prediction Center watch archive, through the Iowa Environmental Mesonet. From 1997 to late 2005 the counties in a watch are the ones whose center falls inside its outline. From late 2005 they are the counties the local offices listed. |
| Mesoscale discussions | 2003 | Storm Prediction Center, through the Iowa Environmental Mesonet. Placed on the map by their outline; a county counts when its center falls inside. |
| Every other VTEC product: winter, flood, heat, wind, fire, fog, marine, coastal and tropical warnings, watches, advisories and statements | 2005 | Iowa Environmental Mesonet VTEC archive. Complete from November 2005, when the codes that identify each event became operational everywhere. Products for forecast zones are filed under the counties those zones cover today. |
| Special weather statements with a storm outline | 2006 (first on file 2005) | Iowa Environmental Mesonet. Only statements that carried a polygon, which is how offices describe strong storms below warning criteria. Statements for whole zones (fog, winter, heat) are not in any public archive that can be read in bulk. |
Before these years the products either were not issued under these names or survive only on paper. Tornado warnings as a national product began in the 1950s and the watch and warning system took its current form in 1965; no archive of them before 1986 can be read in bulk. The counties a zone-based product covered are the counties its zones cover today, so a zone redrawn since is filed under today's counties.
Nearby
Sources
National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Rebuilt daily.