Alert archive / California / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in California, 2026

114 severe thunderstorm warnings in 2026. 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 2026. Tap one for its archive.

Severe Thunderstorm Warnings: 114
Busiest month: April49 severe thunderstorm warnings
Busiest day: April 10, 202616 severe thunderstorm warnings

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

20 of 114 severe thunderstorm warnings covering California in 2026 had a qualifying storm report inside them; 78 of 155 hail, wind and damage reports fell inside a warning, on average 31 minutes after it went out.

California, 2026

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Severe thunderstorm warnings	114	20	82%	155	50%	31 min

Each office's whole area, 2026

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Hanford, CA: severe thunderstorm warnings	16	2	88%	7	29%	21 min
NWS Sacramento, CA: severe thunderstorm warnings	39	2	95%	6	33%	8 min
NWS San Francisco Bay Area, CA: severe thunderstorm warnings	0			3	0%
NWS Eureka, CA: severe thunderstorm warnings	4	2	50%	12	42%	11 min
NWS San Diego, CA: severe thunderstorm warnings	7	2	71%	9	56%	17 min
NWS Los Angeles, CA: severe thunderstorm warnings	10	6	40%	96	58%	35 min
NWS Las Vegas, NV: severe thunderstorm warnings	61	10	84%	46	24%	19 min
NWS Phoenix, AZ: severe thunderstorm warnings	137	22	84%	58	72%	18 min
NWS Medford, OR: severe thunderstorm warnings	33	3	91%	10	40%	20 min
NWS Reno, NV: severe thunderstorm warnings	22	1	95%	19	5%	16 min

An office's figures cover every county it serves, including across state lines.

The year is still running; reports filed late and damage surveys can still change these figures.

Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.

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
Jan 3, 10:40 AM PST	Severe Thunderstorm Warning Considerable damage threat	EKA	Humboldt	35 min
Jan 3, 11:10 AM PST	Severe Thunderstorm Warning Considerable damage threat	EKA	Humboldt	35 min
Feb 16, 6:36 AM PST	Severe Thunderstorm Warning	LOX	San Luis Obispo	24 min
Feb 16, 6:38 AM PST	Severe Thunderstorm Warning	LOX	San Luis Obispo	37 min
Feb 16, 8:06 AM PST	Severe Thunderstorm Warning	LOX	Santa Barbara	84 min
Feb 16, 10:47 AM PST	Severe Thunderstorm Warning	LOX	Los Angeles	88 min
Feb 16, 1:44 PM PST	Severe Thunderstorm Warning	LOX	Ventura	20 min
Feb 17, 6:13 PM PST	Severe Thunderstorm Warning	LOX	San Luis Obispo	92 min
Feb 17, 7:08 PM PST	Severe Thunderstorm Warning	HNX	Kings, Tulare	37 min
Feb 17, 7:10 PM PST	Severe Thunderstorm Warning	LOX	San Luis Obispo, Santa Barbara	95 min
Feb 17, 9:23 PM PST	Severe Thunderstorm Warning Considerable damage threat	LOX	Santa Barbara	80 min
Feb 18, 12:18 AM PST	Severe Thunderstorm Warning Considerable damage threat	LOX	Los Angeles	87 min
Feb 18, 1:26 AM PST	Severe Thunderstorm Warning	SGX	Orange, Riverside, San Bernardino	64 min
Feb 18, 1:34 AM PST	Severe Thunderstorm Warning	LOX	Los Angeles	24 min
Feb 18, 2:28 AM PST	Severe Thunderstorm Warning	SGX	Orange, Riverside, San Bernardino, San Diego	62 min
Mar 31, 6:34 PM PDT	Severe Thunderstorm Warning	STO	Butte, Glenn, Tehama	26 min
Apr 8, 5:37 PM PDT	Severe Thunderstorm Warning	STO	Colusa, Sutter	38 min
Apr 8, 6:23 PM PDT	Severe Thunderstorm Warning	STO	Butte, Colusa, Sutter	37 min
Apr 8, 7:22 PM PDT	Severe Thunderstorm Warning	STO	Butte, Glenn	23 min
Apr 8, 7:32 PM PDT	Severe Thunderstorm Warning	STO	Butte, Colusa, Glenn	43 min
Apr 8, 7:39 PM PDT	Severe Thunderstorm Warning	STO	Butte, Glenn	27 min
Apr 9, 12:39 PM PDT	Severe Thunderstorm Warning	EKA	Humboldt	29 min
Apr 9, 12:48 PM PDT	Severe Thunderstorm Warning	MFR	Siskiyou	27 min
Apr 9, 1:12 PM PDT	Severe Thunderstorm Warning	MFR	Siskiyou	33 min
Apr 9, 3:36 PM PDT	Severe Thunderstorm Warning	STO	Shasta	14 min
Apr 9, 3:46 PM PDT	Severe Thunderstorm Warning	STO	Tehama	29 min
Apr 9, 4:09 PM PDT	Severe Thunderstorm Warning	STO	Tehama	36 min
Apr 9, 5:01 PM PDT	Severe Thunderstorm Warning	STO	Shasta, Tehama	29 min
Apr 9, 5:22 PM PDT	Severe Thunderstorm Warning	STO	Shasta	38 min
Apr 9, 5:29 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Madera, Merced	61 min
Apr 9, 6:12 PM PDT	Severe Thunderstorm Warning Considerable damage threat	HNX	Fresno, Madera	16 min
Apr 9, 6:24 PM PDT	Severe Thunderstorm Warning	HNX	Madera, Merced	34 min
Apr 9, 6:52 PM PDT	Severe Thunderstorm Warning	STO	San Joaquin, Stanislaus	38 min
Apr 9, 7:14 PM PDT	Severe Thunderstorm Warning	STO	San Joaquin, Stanislaus	31 min
Apr 9, 7:39 PM PDT	Severe Thunderstorm Warning	STO	San Joaquin, Stanislaus	36 min
Apr 10, 7:50 AM PDT	Severe Thunderstorm Warning	STO	Butte, Nevada, Plumas, Sierra, Yuba	40 min
Apr 10, 1:55 PM PDT	Severe Thunderstorm Warning	STO	San Joaquin, Stanislaus	35 min
Apr 10, 2:09 PM PDT	Severe Thunderstorm Warning	HNX	Merced	36 min
Apr 10, 2:13 PM PDT	Severe Thunderstorm Warning	STO	Stanislaus	15 min
Apr 10, 2:38 PM PDT	Severe Thunderstorm Warning	STO	Stanislaus	26 min
Apr 10, 2:40 PM PDT	Severe Thunderstorm Warning	STO	Calaveras, San Joaquin, Stanislaus	35 min
Apr 10, 3:00 PM PDT	Severe Thunderstorm Warning	STO	Sacramento, San Joaquin, Solano, Yolo	30 min
Apr 10, 4:08 PM PDT	Severe Thunderstorm Warning	STO	Calaveras, Tuolumne	25 min
Apr 10, 6:36 PM PDT	Severe Thunderstorm Warning	STO	Calaveras, San Joaquin, Stanislaus	24 min
Apr 10, 6:56 PM PDT	Severe Thunderstorm Warning	STO	Calaveras, San Joaquin, Stanislaus	49 min
Apr 10, 7:06 PM PDT	Severe Thunderstorm Warning	STO	Butte, Colusa, Glenn	39 min
Apr 10, 8:39 PM PDT	Severe Thunderstorm Warning	STO	Amador, Calaveras, Tuolumne	36 min
Apr 12, 1:43 PM PDT	Severe Thunderstorm Warning	STO	Butte, Glenn, Tehama	32 min
Apr 12, 3:06 PM PDT	Severe Thunderstorm Warning	STO	Butte	24 min
Apr 12, 4:41 PM PDT	Severe Thunderstorm Warning	STO	Tehama	34 min
Apr 21, 2:54 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Madera	24 min
Apr 21, 3:10 PM PDT	Severe Thunderstorm Warning	STO	Glenn	50 min
Apr 21, 3:19 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Madera, Merced	26 min
Apr 21, 3:20 PM PDT	Severe Thunderstorm Warning	STO	Tehama	40 min
Apr 21, 3:43 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Madera, Merced	32 min
Apr 21, 3:56 PM PDT	Severe Thunderstorm Warning	STO	Butte, Glenn, Tehama	49 min
Apr 21, 4:05 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Madera	25 min
Apr 21, 4:09 PM PDT	Severe Thunderstorm Warning	HNX	Madera	36 min
Apr 21, 4:24 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Madera	36 min
Apr 21, 4:30 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Madera	30 min
Apr 21, 4:41 PM PDT	Severe Thunderstorm Warning	HNX	Madera	34 min
Apr 21, 4:54 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Madera	36 min
Apr 21, 5:11 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Tulare	34 min
Apr 21, 5:39 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Tulare	36 min
May 3, 2:34 PM PDT	Severe Thunderstorm Warning	STO	Plumas, Sierra, Yuba	41 min
May 3, 4:16 PM PDT	Severe Thunderstorm Warning	STO	Butte, Plumas, Tehama	34 min
May 3, 4:47 PM PDT	Severe Thunderstorm Warning	STO	Shasta, Tehama	43 min
May 27, 4:36 PM PDT	Severe Thunderstorm Warning	MFR	Siskiyou	39 min
May 27, 5:09 PM PDT	Severe Thunderstorm Warning	MFR	Siskiyou	27 min
May 27, 5:35 PM PDT	Severe Thunderstorm Warning	MFR	Siskiyou	40 min
May 27, 5:40 PM PDT	Severe Thunderstorm Warning	MFR	Siskiyou	18 min
Jun 18, 4:50 PM PDT	Severe Thunderstorm Warning	STO	Alpine, Tuolumne	40 min
Jun 18, 7:17 PM PDT	Severe Thunderstorm Warning	REV	El Dorado, Placer	23 min
Jun 18, 8:04 PM PDT	Severe Thunderstorm Warning	STO	Nevada, Placer	26 min
Jun 18, 10:07 PM PDT	Severe Thunderstorm Warning	REV	Plumas	38 min
Jun 19, 3:07 PM PDT	Severe Thunderstorm Warning	REV	Lassen, Sierra	23 min
Jun 19, 3:31 PM PDT	Severe Thunderstorm Warning	REV	Lassen, Plumas, Sierra	44 min
Jul 17, 5:57 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	48 min
Jul 17, 7:24 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	66 min
Aug 9, 4:13 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	32 min
Aug 10, 1:12 PM PDT	Severe Thunderstorm Warning	SGX	San Diego	63 min
Aug 10, 2:43 PM PDT	Severe Thunderstorm Warning	SGX	Riverside	47 min
Aug 10, 4:36 PM PDT	Severe Thunderstorm Warning	PSR	Imperial	24 min
Aug 10, 4:58 PM PDT	Severe Thunderstorm Warning	PSR	Imperial	32 min
Aug 10, 5:02 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	43 min
Aug 11, 2:11 PM PDT	Severe Thunderstorm Warning	SGX	San Diego	22 min
Aug 11, 2:14 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	46 min
Aug 11, 3:03 PM PDT	Severe Thunderstorm Warning	SGX	San Diego	59 min
Aug 11, 3:25 PM PDT	Severe Thunderstorm Warning	PSR	Riverside, San Bernardino	50 min
Aug 11, 3:36 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	39 min
Aug 11, 3:50 PM PDT	Severe Thunderstorm Warning Considerable damage threat	VEF	San Bernardino	40 min
Aug 11, 4:12 PM PDT	Severe Thunderstorm Warning Considerable damage threat	VEF	San Bernardino	48 min
Aug 11, 5:42 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	48 min
Aug 11, 6:54 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	51 min
Aug 12, 2:53 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	52 min
Aug 12, 3:47 PM PDT	Severe Thunderstorm Warning Considerable damage threat	PSR	Imperial	43 min
Aug 12, 3:58 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	47 min
Aug 12, 4:26 PM PDT	Severe Thunderstorm Warning	PSR	Imperial	49 min
Aug 12, 4:58 PM PDT	Severe Thunderstorm Warning	PSR	Imperial	47 min
Aug 13, 12:07 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	38 min
Aug 13, 12:43 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	47 min
Aug 13, 12:44 PM PDT	Severe Thunderstorm Warning	REV	Mono	46 min
Aug 15, 12:45 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	45 min
Aug 15, 4:49 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	41 min
Aug 15, 5:20 PM PDT	Severe Thunderstorm Warning	PSR	Imperial	13 min
Aug 15, 5:42 PM PDT	Severe Thunderstorm Warning	PSR	Imperial	24 min
Sep 1, 5:37 PM PDT	Severe Thunderstorm Warning	PSR	Imperial	38 min
Sep 8, 5:08 PM PDT	Severe Thunderstorm Warning	SGX	Riverside, San Diego	35 min
Sep 16, 5:12 PM PDT	Severe Thunderstorm Warning	MFR	Siskiyou	13 min
Sep 16, 5:30 PM PDT	Severe Thunderstorm Warning	EKA	Mendocino, Trinity	45 min
Sep 16, 5:40 PM PDT	Severe Thunderstorm Warning	VEF	San Bernardino	50 min
Sep 21, 3:29 PM PDT	Severe Thunderstorm Warning	STO	Plumas, Sierra	30 min
Sep 21, 4:32 PM PDT	Severe Thunderstorm Warning	STO	Plumas	28 min
Sep 21, 4:52 PM PDT	Severe Thunderstorm Warning	STO	Plumas	23 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record The radar archive 2025

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. Warning verification from the Mesonet's Cow. Rebuilt daily.