Alert archive / California / Severe Thunderstorm Warnings
Severe Thunderstorm Warnings in California, 2021
51 severe thunderstorm warnings in 2021. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of severe thunderstorm warnings reaches back to 1986.
Severe Thunderstorm Warnings by county
Each county as a circle sized by its count in 2021. Tap one for its archive.
- Severe Thunderstorm Warnings
- 51
- Busiest month
- September18 severe thunderstorm warnings
- Busiest day
- September 9, 20219 severe thunderstorm warnings
Over time
By month
The alerts
Every alert, in the order issued. Times are local, Pacific Time. Each opens its own page with the text, the map, the radar and the sounding.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 10, 2:46 PM PST | Severe Thunderstorm Warning | HNX | Fresno | 44 min |
| Mar 23, 4:32 PM PDT | Severe Thunderstorm Warning | SGX | Riverside | 40 min |
| Apr 25, 5:14 PM PDT | Severe Thunderstorm Warning | STO | Tehama | 46 min |
| Jun 22, 4:01 PM PDT | Severe Thunderstorm Warning | REV | Modoc | 44 min |
| Jun 23, 4:03 PM PDT | Severe Thunderstorm Warning | REV | Lassen | 42 min |
| Jun 23, 4:27 PM PDT | Severe Thunderstorm Warning | REV | Lassen, Plumas | 33 min |
| Jun 23, 5:38 PM PDT | Severe Thunderstorm Warning | PSR | Riverside | 37 min |
| Jun 28, 4:06 PM PDT | Severe Thunderstorm Warning | REV | Alpine, Mono | 54 min |
| Jun 29, 11:44 AM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 27 min |
| Jun 30, 2:51 PM PDT | Severe Thunderstorm Warning | HNX | Fresno, Madera | 24 min |
| Jun 30, 3:18 PM PDT | Severe Thunderstorm Warning | HNX | Fresno, Madera | 27 min |
| Jul 1, 4:45 PM PDT | Severe Thunderstorm Warning | REV | Alpine | 45 min |
| Jul 22, 4:22 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 53 min |
| Jul 25, 4:01 PM PDT | Severe Thunderstorm Warning | PSR | Riverside, San Bernardino | 29 min |
| Jul 25, 4:14 PM PDT | Severe Thunderstorm Warning | SGX | Riverside | 36 min |
| Jul 25, 9:55 PM PDT | Severe Thunderstorm Warning | VEF | Inyo, San Bernardino | 50 min |
| Jul 30, 1:14 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 61 min |
| Jul 30, 3:17 PM PDT | Severe Thunderstorm Warning | SGX | Riverside | 58 min |
| Jul 30, 5:29 PM PDT | Severe Thunderstorm Warning | PSR | Imperial | 46 min |
| Jul 30, 6:11 PM PDT | Severe Thunderstorm Warning | PSR | Riverside | 79 min |
| Aug 10, 5:13 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 92 min |
| Aug 10, 6:30 PM PDT | Severe Thunderstorm Warning | PSR | Riverside | 45 min |
| Aug 10, 6:43 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 47 min |
| Aug 10, 7:26 PM PDT | Severe Thunderstorm Warning | PSR | Imperial, Riverside | 49 min |
| Aug 10, 8:18 PM PDT | Severe Thunderstorm Warning | PSR | Imperial, Riverside | 57 min |
| Aug 13, 2:23 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 52 min |
| Aug 13, 3:20 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 40 min |
| Aug 13, 4:04 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 41 min |
| Aug 13, 4:55 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 50 min |
| Aug 31, 4:13 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 62 min |
| Aug 31, 4:30 PM PDT | Severe Thunderstorm Warning | PSR | Imperial | 75 min |
| Aug 31, 5:17 PM PDT | Severe Thunderstorm Warning | SGX | Riverside, San Diego | 58 min |
| Sep 9, 1:05 PM PDT | Severe Thunderstorm Warning | SGX | San Bernardino | 40 min |
| Sep 9, 1:19 PM PDT | Severe Thunderstorm Warning | SGX | San Bernardino | 22 min |
| Sep 9, 1:29 PM PDT | Severe Thunderstorm Warning | PSR | Riverside | 46 min |
| Sep 9, 1:47 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 58 min |
| Sep 9, 2:00 PM PDT | Severe Thunderstorm Warning | PSR | Riverside | 45 min |
| Sep 9, 2:31 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 59 min |
| Sep 9, 2:54 PM PDT | Severe Thunderstorm Warning | SGX | San Bernardino | 66 min |
| Sep 9, 3:10 PM PDT | Severe Thunderstorm Warning | SGX | Riverside, San Bernardino | 50 min |
| Sep 9, 4:35 PM PDT | Severe Thunderstorm Warning | SGX | Riverside, San Bernardino | 55 min |
| Sep 10, 4:03 PM PDT | Severe Thunderstorm Warning | PSR | Imperial | 42 min |
| Sep 17, 3:08 PM PDT | Severe Thunderstorm Warning | PSR | Riverside | 52 min |
| Sep 24, 7:33 AM PDT | Severe Thunderstorm Warning | PSR | Imperial | 42 min |
| Sep 24, 12:13 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 31 min |
| Sep 24, 1:24 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 51 min |
| Sep 24, 2:11 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 49 min |
| Sep 24, 2:41 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 64 min |
| Sep 24, 3:20 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 55 min |
| Oct 25, 4:04 PM PDT | Severe Thunderstorm Warning | HNX | Kern, Kings, Tulare | 26 min |
| Oct 25, 4:42 PM PDT | Severe Thunderstorm Warning | HNX | Kern | 48 min |
By county
Every county with at least one alert. A county page lists each alert that covered it.
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20202022
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.