Alert archive / California / Flash Flood Warnings

Flash Flood Warnings in California, 2023

240 flash flood warnings in 2023. 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 flash flood warnings reaches back to 1986.

Flash Flood Warnings by county

Each county as a circle sized by its count in 2023. Tap one for its archive.

Flash Flood Warnings: 240
Busiest month: August94 flash flood warnings
Busiest day: August 20, 202328 flash flood warnings

Over time

By month

Warning verification

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

83 of 240 flash flood warnings covering California in 2023 had a flash flood report inside them; 249 of 497 flash flood reports fell inside a warning, on average 174 minutes after it went out.

California, 2023

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Flash flood warnings	240	83	65%	497	50%	174 min

Each office's whole area, 2023

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Hanford, CA: flash flood warnings	60	8	87%	59	20%	193 min
NWS Las Vegas, NV: flash flood warnings	146	56	62%	184	68%	114 min
NWS San Francisco Bay Area, CA: flash flood warnings	11	1	91%	8	13%	172 min
NWS Sacramento, CA: flash flood warnings	8	4	50%	24	33%	38 min
NWS Eureka, CA: flash flood warnings	4	0	100%	18	0%
NWS Los Angeles, CA: flash flood warnings	30	22	27%	190	73%	210 min
NWS Medford, OR: flash flood warnings	6	2	67%	3	67%	37 min
NWS San Diego, CA: flash flood warnings	19	8	58%	89	13%	141 min
NWS Phoenix, AZ: flash flood warnings	47	21	55%	50	88%	96 min
NWS Reno, NV: flash flood warnings	18	0	100%	16	0%

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

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
Dec 31, 9:13 PM PST	Flash Flood Warning Considerable damage threat	STO	Sacramento	12 hr
Dec 31, 11:28 PM PST	Flash Flood Warning Considerable damage threat	STO	Sacramento	9 hr
Jan 1, 8:47 AM PST	Flash Flood Warning Considerable damage threat	STO	Sacramento	25 hr
Jan 4, 6:05 PM PST	Flash Flood Warning Considerable damage threat	MTR	San Benito	2 hr
Jan 4, 6:17 PM PST	Flash Flood Warning Considerable damage threat	MTR	Monterey	3 hr
Jan 4, 8:07 PM PST	Flash Flood Warning Considerable damage threat	MTR	San Benito	15 hr
Jan 9, 5:34 AM PST	Flash Flood Warning Considerable damage threat	MTR	Monterey	5 hr
Jan 9, 6:46 AM PST	Flash Flood Warning Considerable damage threat	MTR	Santa Cruz	6 hr
Jan 9, 10:54 AM PST	Flash Flood Warning Considerable damage threat	HNX	Fresno, Madera	3 hr
Jan 9, 10:56 AM PST	Flash Flood Warning Considerable damage threat	LOX	San Luis Obispo	6 hr
Jan 9, 10:56 AM PST	Flash Flood Warning Considerable damage threat	LOX	Santa Barbara, Ventura	6 hr
Jan 9, 2:32 PM PST	Flash Flood Warning Considerable damage threat	LOX	San Luis Obispo, Santa Barbara	4 hr
Jan 9, 2:57 PM PST	Flash Flood Warning Considerable damage threat	LOX	Santa Barbara	4 hr
Jan 9, 3:17 PM PST	Flash Flood Warning Considerable damage threat	LOX	Los Angeles, Ventura	6 hr
Jan 9, 4:44 PM PST	Flash Flood Warning Considerable damage threat	LOX	San Luis Obispo, Santa Barbara	4 hr
Jan 9, 5:08 PM PST	Flash Flood Warning Considerable damage threat	LOX	Ventura	4 hr
Jan 9, 6:43 PM PST	Flash Flood Warning	LOX	Los Angeles	6 hr
Jan 9, 7:15 PM PST	Flash Flood Warning Considerable damage threat	LOX	Los Angeles	6 hr
Jan 10, 4:47 AM PST	Flash Flood Warning Considerable damage threat	LOX	San Luis Obispo	58 min
Jan 10, 12:19 PM PST	Flash Flood Warning Considerable damage threat	MTR	City and County of San Francisco, San Mateo	85 min
Jan 10, 1:11 PM PST	Flash Flood Warning Considerable damage threat	MTR	Monterey	6 hr
Jan 10, 4:04 PM PST	Flash Flood Warning Considerable damage threat	HNX	Tulare	86 min
Jan 14, 11:14 PM PST	Flash Flood Warning	HNX	Fresno, Madera	61 min
Feb 24, 2:16 PM PST	Flash Flood Warning Considerable damage threat	LOX	Santa Barbara, Ventura	8 hr
Feb 24, 2:16 PM PST	Flash Flood Warning Considerable damage threat	LOX	Los Angeles	14 hr
Feb 24, 9:51 PM PST	Flash Flood Warning Considerable damage threat	LOX	Ventura	3 hr
Mar 9, 11:51 PM PST	Flash Flood Warning Considerable damage threat	MTR	Santa Cruz	13 hr
Mar 10, 5:10 AM PST	Flash Flood Warning Considerable damage threat	LOX	San Luis Obispo	13 hr
Mar 10, 6:31 AM PST	Flash Flood Warning Considerable damage threat	HNX	Tulare	10 hr
Mar 10, 6:32 AM PST	Flash Flood Warning EmergencyConsiderable damage threat	HNX	Tulare	25 hr
Mar 10, 6:38 AM PST	Flash Flood Warning Considerable damage threat	HNX	Fresno	6 hr
Mar 10, 7:20 AM PST	Flash Flood Warning Considerable damage threat	LOX	San Luis Obispo	11 hr
Mar 10, 7:29 AM PST	Flash Flood Warning Considerable damage threat	HNX	Fresno	4 hr
Mar 10, 7:29 AM PST	Flash Flood Warning Considerable damage threat	HNX	Tulare	7 hr
Mar 10, 7:59 AM PST	Flash Flood Warning	HNX	Fresno, Madera	6 hr
Mar 10, 8:21 AM PST	Flash Flood Warning Considerable damage threat	HNX	Kings, Tulare	4 hr
Mar 10, 9:17 AM PST	Flash Flood Warning	HNX	Fresno, Madera	3 hr
Mar 10, 9:20 AM PST	Flash Flood Warning	HNX	Mariposa, Tuolumne	115 min
Mar 10, 10:44 AM PST	Flash Flood Warning EmergencyCatastrophic damage threat	HNX	Kern, Tulare	7 hr
Mar 10, 11:06 AM PST	Flash Flood Warning	HNX	Fresno	5 hr
Mar 10, 5:51 PM PST	Flash Flood Warning Considerable damage threat	HNX	Kern, Tulare	14 hr
Mar 10, 6:16 PM PST	Flash Flood Warning	HNX	Madera, Mariposa	4 hr
Mar 10, 7:01 PM PST	Flash Flood Warning	HNX	Fresno, Madera, Mariposa	3 hr
Mar 10, 8:56 PM PST	Flash Flood Warning Considerable damage threat	HNX	Fresno	3 hr
Mar 10, 9:07 PM PST	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Mar 10, 10:19 PM PST	Flash Flood Warning	HNX	Madera, Mariposa	3 hr
Mar 11, 12:34 AM PST	Flash Flood Warning	HNX	Madera	14 hr
Mar 11, 7:59 AM PST	Flash Flood Warning Considerable damage threat	MTR	Monterey	3 hr
Mar 11, 8:41 AM PST	Flash Flood Warning Considerable damage threat	MTR	Monterey, Santa Cruz	3 hr
Mar 11, 10:05 AM PST	Flash Flood Warning Considerable damage threat	VEF	Inyo	26 min
Mar 11, 1:11 PM PST	Flash Flood Warning	HNX	Fresno, Madera, Mariposa	5 hr
Mar 11, 1:57 PM PST	Flash Flood Warning Considerable damage threat	HNX	Tulare	11 hr
Mar 11, 3:08 PM PST	Flash Flood Warning Considerable damage threat	STO	Calaveras, Stanislaus, Tuolumne	3 hr
Mar 11, 4:04 PM PST	Flash Flood Warning	HNX	Fresno, Madera	7 hr
Mar 11, 4:11 PM PST	Flash Flood Warning	HNX	Kern	9 hr
Mar 11, 5:32 PM PST	Flash Flood Warning	HNX	Tulare	7 hr
Mar 11, 5:49 PM PST	Flash Flood Warning	HNX	Mariposa, Tuolumne	105 min
Mar 11, 6:49 PM PST	Flash Flood Warning	HNX	Tulare	3 hr
Mar 11, 11:13 PM PST	Flash Flood Warning	HNX	Tulare	3 hr
Mar 12, 4:40 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Mariposa, Tuolumne	5 hr
Mar 12, 6:15 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Fresno, Madera	113 min
Mar 12, 6:31 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Fresno, Madera	97 min
Mar 12, 7:12 PM PDT	Flash Flood Warning	HNX	Fresno	74 min
Mar 14, 11:14 AM PDT	Flash Flood Warning Considerable damage threat	MTR	Santa Cruz	61 min
Mar 14, 6:12 PM PDT	Flash Flood Warning	STO	Shasta, Tehama	3 hr
Mar 15, 3:38 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	4 hr
Mar 15, 4:41 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	59 min
Mar 15, 6:20 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Mar 15, 6:34 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
May 4, 2:23 PM PDT	Flash Flood Warning	REV	Lassen, Plumas	52 min
May 20, 2:22 PM PDT	Flash Flood Warning	REV	Alpine	69 min
May 20, 4:38 PM PDT	Flash Flood Warning	HNX	Fresno	48 min
May 20, 6:28 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
May 21, 3:58 PM PDT	Flash Flood Warning	HNX	Madera	55 min
May 21, 5:43 PM PDT	Flash Flood Warning	HNX	Tulare	80 min
May 21, 6:48 PM PDT	Flash Flood Warning	HNX	Kern	57 min
May 21, 6:51 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	2 hr
May 21, 7:04 PM PDT	Flash Flood Warning	HNX	Kern	101 min
May 21, 7:24 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
May 29, 5:04 PM PDT	Flash Flood Warning	REV	Alpine, Mono	106 min
May 30, 3:08 PM PDT	Flash Flood Warning	MFR	Siskiyou	52 min
May 30, 4:54 PM PDT	Flash Flood Warning Considerable damage threat	LOX	Ventura	103 min
May 31, 4:09 PM PDT	Flash Flood Warning	REV	Alpine, Mono	111 min
Jun 3, 6:21 PM PDT	Flash Flood Warning	HNX	Fresno, Tulare	70 min
Jun 4, 2:24 PM PDT	Flash Flood Warning	REV	Alpine	51 min
Jun 6, 5:04 PM PDT	Flash Flood Warning	STO	Plumas	4 hr
Jun 7, 2:32 PM PDT	Flash Flood Warning	REV	Lassen, Plumas	118 min
Jun 8, 2:38 PM PDT	Flash Flood Warning	REV	Alpine, El Dorado	3 hr
Jun 8, 4:12 PM PDT	Flash Flood Warning	MFR	Siskiyou	79 min
Jun 8, 4:52 PM PDT	Flash Flood Warning	REV	Lassen, Plumas	113 min
Jun 10, 5:47 PM PDT	Flash Flood Warning	LOX	Ventura	34 min
Jun 11, 1:23 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Jun 11, 2:03 PM PDT	Flash Flood Warning	REV	Alpine	4 hr
Jun 11, 4:22 PM PDT	Flash Flood Warning	REV	Alpine, Mono	83 min
Jun 11, 4:44 PM PDT	Flash Flood Warning	HNX	Kern	105 min
Jun 11, 5:08 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Jun 11, 5:17 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Jun 11, 6:10 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Jun 11, 6:49 PM PDT	Flash Flood Warning	STO	Butte, Plumas	6 hr
Jun 11, 6:59 PM PDT	Flash Flood Warning	REV	Lassen, Plumas	105 min
Jun 15, 10:28 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Jun 16, 3:35 PM PDT	Flash Flood Warning	LOX	Ventura	68 min
Jul 19, 7:10 PM PDT	Flash Flood Warning	REV	Mono	3 hr
Jul 30, 5:09 PM PDT	Flash Flood Warning Considerable damage threat	SGX	San Bernardino	85 min
Aug 1, 2:41 PM PDT	Flash Flood Warning Considerable damage threat	SGX	San Diego	2 hr
Aug 1, 3:52 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 1, 4:11 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo, San Bernardino	3 hr
Aug 2, 9:21 AM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	114 min
Aug 2, 11:07 AM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 2, 2:17 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 11, 1:31 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Aug 11, 3:41 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Aug 13, 3:58 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 13, 6:35 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial, Riverside	3 hr
Aug 15, 4:15 PM PDT	Flash Flood Warning Considerable damage threat	SGX	San Diego	87 min
Aug 16, 1:19 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 16, 1:35 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 16, 2:42 PM PDT	Flash Flood Warning Considerable damage threat	SGX	San Diego	3 hr
Aug 16, 4:48 PM PDT	Flash Flood Warning Considerable damage threat	SGX	Riverside, San Diego	3 hr
Aug 18, 4:09 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 18, 4:47 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Riverside, San Bernardino	3 hr
Aug 18, 4:47 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	2 hr
Aug 18, 4:56 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	2 hr
Aug 18, 5:40 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	5 hr
Aug 18, 6:05 PM PDT	Flash Flood Warning	REV	Alpine, Mono	85 min
Aug 18, 7:09 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 18, 8:21 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 18, 9:19 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 19, 4:49 AM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial	4 hr
Aug 19, 4:55 AM PDT	Flash Flood Warning Considerable damage threat	SGX	San Diego	114 min
Aug 19, 8:46 AM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial, Riverside	3 hr
Aug 19, 12:16 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Aug 19, 1:15 PM PDT	Flash Flood Warning Considerable damage threat	EKA	Trinity	3 hr
Aug 19, 1:16 PM PDT	Flash Flood Warning	HNX	Kern	84 min
Aug 19, 1:36 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Aug 19, 1:53 PM PDT	Flash Flood Warning	HNX	Kern	112 min
Aug 19, 2:01 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Aug 19, 2:51 PM PDT	Flash Flood Warning	HNX	Kern	72 min
Aug 19, 3:12 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Aug 19, 3:37 PM PDT	Flash Flood Warning	MFR	Siskiyou	113 min
Aug 19, 3:50 PM PDT	Flash Flood Warning	EKA	Trinity	85 min
Aug 19, 4:56 PM PDT	Flash Flood Warning Considerable damage threat	STO	Shasta, Tehama	2 hr
Aug 19, 6:29 PM PDT	Flash Flood Warning	MFR	Siskiyou	61 min
Aug 19, 7:11 PM PDT	Flash Flood Warning	MFR	Siskiyou	114 min
Aug 20, 10:54 AM PDT	Flash Flood Warning Considerable damage threat	LOX	Los Angeles	8 hr
Aug 20, 11:25 AM PDT	Flash Flood Warning Considerable damage threat	SGX	San Diego	3 hr
Aug 20, 11:48 AM PDT	Flash Flood Warning Considerable damage threat	LOX	Los Angeles, Ventura	8 hr
Aug 20, 11:55 AM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial	6 hr
Aug 20, 12:02 PM PDT	Flash Flood Warning	HNX	Kern	3 hr
Aug 20, 12:03 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Kern	5 hr
Aug 20, 12:48 PM PDT	Flash Flood Warning Considerable damage threat	SGX	San Diego	3 hr
Aug 20, 1:04 PM PDT	Flash Flood Warning Considerable damage threat	SGX	San Diego	3 hr
Aug 20, 1:32 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial, Riverside	4 hr
Aug 20, 1:40 PM PDT	Flash Flood Warning Considerable damage threat	SGX	Riverside	10 hr
Aug 20, 1:51 PM PDT	Flash Flood Warning Considerable damage threat	SGX	Riverside	10 hr
Aug 20, 2:16 PM PDT	Flash Flood Warning	HNX	Kern	3 hr
Aug 20, 2:30 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial, Riverside, San Bernardino	5 hr
Aug 20, 2:31 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	4 hr
Aug 20, 2:35 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Kern	8 hr
Aug 20, 2:58 PM PDT	Flash Flood Warning Considerable damage threat	SGX	Riverside, San Bernardino	5 hr
Aug 20, 3:06 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial	3 hr
Aug 20, 3:10 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo, San Bernardino	18 hr
Aug 20, 3:21 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Kern	2 hr
Aug 20, 3:24 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	8 hr
Aug 20, 3:36 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Kern	114 min
Aug 20, 3:46 PM PDT	Flash Flood Warning Considerable damage threat	SGX	San Diego	74 min
Aug 20, 4:00 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 20, 4:02 PM PDT	Flash Flood Warning	HNX	Kern, Tulare	9 hr
Aug 20, 4:04 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Kern	8 hr
Aug 20, 4:20 PM PDT	Flash Flood Warning Considerable damage threat	LOX	Ventura	3 hr
Aug 20, 5:00 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Kern	8 hr
Aug 20, 5:18 PM PDT	Flash Flood Warning	SGX	Riverside, San Bernardino	3 hr
Aug 20, 5:19 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Kern	6 hr
Aug 20, 5:25 PM PDT	Flash Flood Warning Considerable damage threat	LOX	Ventura	2 hr
Aug 20, 5:26 PM PDT	Flash Flood Warning	HNX	Kern	7 hr
Aug 20, 5:36 PM PDT	Flash Flood Warning	HNX	Kern	6 hr
Aug 20, 5:37 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo, San Bernardino	15 hr
Aug 20, 5:48 PM PDT	Flash Flood Warning Considerable damage threat	LOX	Ventura	117 min
Aug 20, 5:59 PM PDT	Flash Flood Warning	HNX	Kern	5 hr
Aug 20, 6:02 PM PDT	Flash Flood Warning	HNX	Kern	6 hr
Aug 20, 6:29 PM PDT	Flash Flood Warning Considerable damage threat	LOX	Los Angeles	10 hr
Aug 20, 6:50 PM PDT	Flash Flood Warning	HNX	Kern	5 hr
Aug 20, 7:04 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	14 hr
Aug 20, 7:22 PM PDT	Flash Flood Warning Considerable damage threat	SGX	San Bernardino	4 hr
Aug 20, 7:31 PM PDT	Flash Flood Warning Considerable damage threat	SGX	Riverside	4 hr
Aug 20, 7:44 PM PDT	Flash Flood Warning Considerable damage threat	LOX	Ventura	7 hr
Aug 20, 9:12 PM PDT	Flash Flood Warning Considerable damage threat	HNX	Kern	3 hr
Aug 20, 10:59 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	6 hr
Aug 20, 11:27 PM PDT	Flash Flood Warning Considerable damage threat	SGX	Riverside, San Bernardino	5 hr
Aug 21, 1:21 AM PDT	Flash Flood Warning	REV	Mono	6 hr
Aug 21, 1:31 AM PDT	Flash Flood Warning	VEF	Inyo	5 hr
Aug 21, 3:27 PM PDT	Flash Flood Warning	HNX	Kern	109 min
Aug 21, 3:52 PM PDT	Flash Flood Warning Considerable damage threat	LOX	San Luis Obispo	2 hr
Aug 21, 4:28 PM PDT	Flash Flood Warning	MFR	Siskiyou	3 hr
Aug 21, 5:13 PM PDT	Flash Flood Warning	HNX	Kern	3 hr
Aug 24, 1:30 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo, San Bernardino	3 hr
Aug 24, 2:41 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Aug 24, 5:02 PM PDT	Flash Flood Warning Considerable damage threat	EKA	Trinity	66 min
Aug 31, 7:17 PM PDT	Flash Flood Warning	VEF	San Bernardino	88 min
Sep 1, 1:38 AM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	5 hr
Sep 1, 3:42 AM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	4 hr
Sep 1, 4:36 AM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Sep 1, 4:45 AM PDT	Flash Flood Warning Considerable damage threat	PSR	Riverside	4 hr
Sep 1, 1:18 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial	4 hr
Sep 1, 1:24 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial	6 hr
Sep 1, 2:03 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial	4 hr
Sep 1, 2:16 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Riverside, San Bernardino	6 hr
Sep 1, 2:33 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	5 hr
Sep 1, 2:52 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	99 min
Sep 1, 2:57 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial, Riverside, San Bernardino	6 hr
Sep 1, 2:58 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo, San Bernardino	4 hr
Sep 1, 3:16 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	4 hr
Sep 1, 3:17 PM PDT	Flash Flood Warning Considerable damage threat	SGX	Riverside	4 hr
Sep 1, 3:33 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	3 hr
Sep 1, 4:04 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	4 hr
Sep 1, 4:13 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Sep 1, 5:15 PM PDT	Flash Flood Warning Considerable damage threat	SGX	Riverside	3 hr
Sep 1, 5:30 PM PDT	Flash Flood Warning Considerable damage threat	EKA	Del Norte	4 hr
Sep 1, 5:59 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	76 min
Sep 1, 6:43 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Sep 1, 6:57 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo, San Bernardino	9 hr
Sep 1, 8:36 PM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo	7 hr
Sep 2, 11:29 AM PDT	Flash Flood Warning Considerable damage threat	VEF	Inyo, San Bernardino	4 hr
Sep 2, 12:43 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Imperial	3 hr
Sep 2, 1:06 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	2 hr
Sep 2, 1:16 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	4 hr
Sep 2, 1:42 PM PDT	Flash Flood Warning Considerable damage threat	PSR	Riverside	3 hr
Sep 2, 2:40 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	50 min
Sep 2, 3:35 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Sep 2, 4:47 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	4 hr
Sep 2, 5:55 PM PDT	Flash Flood Warning	VEF	San Bernardino	3 hr
Sep 12, 3:29 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	2 hr
Sep 12, 5:07 PM PDT	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Sep 12, 8:23 PM PDT	Flash Flood Warning	VEF	San Bernardino	2 hr
Nov 18, 9:31 AM PST	Flash Flood Warning	LOX	San Luis Obispo	96 min
Dec 20, 9:35 PM PST	Flash Flood Warning Considerable damage threat	LOX	Santa Barbara, Ventura	3 hr
Dec 21, 1:52 AM PST	Flash Flood Warning Considerable damage threat	LOX	Ventura	113 min
Dec 21, 8:42 AM PST	Flash Flood Warning Considerable damage threat	LOX	Santa Barbara	7 hr
Dec 22, 3:05 AM PST	Flash Flood Warning Considerable damage threat	VEF	San Bernardino	3 hr
Dec 22, 5:24 PM PST	Flash Flood Warning Considerable damage threat	PSR	Imperial, Riverside	4 hr

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record The radar archive 2022 2024

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.