Alert archive / California / Riverside County

Weather alerts in Riverside County, California, 2020

193 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Riverside County and its neighbors

Each county as a circle sized by its count in 2020. Tap one for its archive.

Alerts: 193
Warnings: 71
Watches: 45
Advisories: 72
Busiest month: March23 alerts
Busiest day: March 12, 202012 alerts

Over time

By month

Warning verification

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

0 of 1 tornado reports fell inside a warning.

Riverside County, 2020

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	0			1	0%
Severe thunderstorm warnings	5	0	100%	1	0%
Flash flood warnings	15	6	60%	8	63%	73 min

Each office's whole area, 2020

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS San Diego, CA: tornado warnings	0			1	0%
NWS San Diego, CA: severe thunderstorm warnings	9	0	100%	4	0%
NWS San Diego, CA: flash flood warnings	14	7	50%	34	65%	91 min
NWS Phoenix, AZ: tornado warnings	0			1	0%
NWS Phoenix, AZ: severe thunderstorm warnings	43	13	70%	41	71%	15 min
NWS Phoenix, AZ: flash flood warnings	47	15	68%	23	87%	100 min

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	Lasted
Jan 3, 1:00 PM PST	High Wind Watch	SGX	24 hr
Jan 4, 1:00 PM PST	High Wind Warning	SGX	49 hr
Jan 4, 1:00 PM PST	Wind Advisory	SGX	56 hr
Jan 15, 1:15 PM PST	Wind Advisory	SGX	39 hr
Jan 21, 7:54 PM PST	Dense Fog Advisory	PSR	14 hr
Jan 27, 8:09 PM PST	High Wind Watch	SGX	17 hr
Jan 27, 8:09 PM PST	Wind Advisory	SGX	4 days
Jan 28, 2:09 AM PST	Wind Advisory	PSR	39 hr
Jan 28, 1:07 PM PST	High Wind Warning	SGX	48 hr
Jan 31, 3:01 PM PST	High Wind Watch	SGX	22 hr
Feb 1, 1:14 PM PST	Wind Advisory	PSR	51 hr
Feb 1, 1:22 PM PST	High Wind Warning	SGX	39 hr
Feb 2, 1:05 PM PST	Freeze Watch	SGX	24 hr
Feb 2, 1:05 PM PST	Freeze Watch	SGX	24 hr
Feb 3, 3:18 AM PST	Wind Advisory	PSR	40 hr
Feb 3, 4:15 AM PST	High Wind Watch	SGX	9 hr
Feb 3, 12:59 PM PST	Freeze Warning	SGX	20 hr
Feb 3, 12:59 PM PST	Wind Advisory	SGX	39 hr
Feb 4, 5:00 AM PST	Freeze Warning	SGX	28 hr
Feb 9, 4:07 AM PST	Winter Weather Advisory	SGX	36 hr
Feb 9, 4:15 AM PST	Wind Advisory	SGX	29 hr
Feb 10, 9:37 AM PST	High Wind Warning	SGX	28 hr
Feb 10, 11:54 AM PST	Wind Advisory	PSR	25 hr
Feb 24, 12:09 PM PST	Wind Advisory	SGX	72 hr
Feb 24, 12:23 PM PST	Wind Advisory	PSR	29 hr
Feb 29, 2:49 AM PST	Wind Advisory	PSR	48 hr
Feb 29, 3:03 AM PST	Wind Advisory	SGX	57 hr
Feb 29, 12:57 PM PST	Winter Weather Advisory	SGX	45 hr
Mar 1, 11:48 AM PST	High Wind Watch	SGX	14 hr
Mar 2, 11:57 AM PST	High Wind Warning	SGX	24 hr
Mar 10, 8:39 PM PDT	Areal Flood Advisory	PSR	4 hr
Mar 11, 3:59 AM PDT	Flash Flood Watch	PSR	64 hr
Mar 11, 1:23 PM PDT	Flash Flood Watch	SGX	44 hr
Mar 12, 10:01 AM PDT	Areal Flood Advisory	SGX	6 hr
Mar 12, 10:39 AM PDT	Areal Flood Advisory	SGX	3 hr
Mar 12, 12:31 PM PDT	Areal Flood Advisory	SGX	6 hr
Mar 12, 12:59 PM PDT	Flash Flood Warning	SGX	3 hr
Mar 12, 1:27 PM PDT	Special Weather Statement	PSR	48 min
Mar 12, 1:32 PM PDT	Flash Flood Warning Considerable damage threat	PSR	4 hr
Mar 12, 2:22 PM PDT	Flash Flood Warning	SGX	3 hr
Mar 12, 2:45 PM PDT	Flash Flood Warning Considerable damage threat	PSR	4 hr
Mar 12, 3:42 PM PDT	Flash Flood Warning Considerable damage threat	PSR	4 hr
Mar 12, 3:43 PM PDT	Winter Weather Advisory	SGX	17 hr
Mar 12, 4:23 PM PDT	Flash Flood Warning Considerable damage threat	PSR	4 hr
Mar 12, 4:42 PM PDT	Flash Flood Warning Considerable damage threat	PSR	4 hr
Mar 12, 5:45 PM PDT	Flash Flood Warning Considerable damage threat	PSR	4 hr
Mar 15, 1:13 PM PDT	Winter Storm Watch	SGX	13 hr
Mar 16, 2:20 AM PDT	Winter Weather Advisory	SGX	28 hr
Mar 17, 1:34 PM PDT	Winter Weather Advisory	SGX	62 hr
Mar 21, 1:42 PM PDT	Winter Weather Advisory	SGX	47 hr
Mar 24, 1:12 PM PDT	Winter Weather Advisory	SGX	67 hr
Apr 4, 3:52 AM PDT	Winter Storm Watch	SGX	24 hr
Apr 5, 3:28 AM PDT	Winter Storm Warning	SGX	6 days
Apr 6, 8:07 AM PDT	Areal Flood Advisory	SGX	3 hr
Apr 6, 10:23 AM PDT	Flash Flood Warning	SGX	3 hr
Apr 6, 1:02 PM PDT	Flash Flood Watch	SGX	4 days
Apr 6, 1:22 PM PDT	Flash Flood Watch	PSR	53 hr
Apr 6, 1:32 PM PDT	Areal Flood Advisory	SGX	3 hr
Apr 6, 4:32 PM PDT	Areal Flood Advisory	SGX	118 min
Apr 6, 6:30 PM PDT	Areal Flood Advisory	SGX	4 hr
Apr 8, 9:06 AM PDT	Areal Flood Advisory	PSR	3 hr
Apr 8, 7:02 PM PDT	Areal Flood Advisory	PSR	118 min
Apr 10, 3:54 AM PDT	Areal Flood Advisory	SGX	4 hr
Apr 10, 7:43 AM PDT	Areal Flood Advisory	SGX	3 hr
Apr 10, 11:28 AM PDT	Areal Flood Advisory	SGX	3 hr
Apr 10, 2:29 PM PDT	Flash Flood Warning Considerable damage threat	SGX	5 hr
Apr 12, 7:52 AM PDT	Wind Advisory	SGX	24 hr
Apr 22, 1:01 PM PDT	Heat Advisory	SGX	3 days
Apr 24, 1:32 PM PDT	Excessive Heat Warning	PSR	71 hr
Apr 24, 1:41 PM PDT	Excessive Heat Warning	SGX	6 days
Apr 25, 1:37 PM PDT	Excessive Heat Watch	PSR	38 hr
Apr 27, 3:44 AM PDT	Excessive Heat Warning	PSR	4 days
May 3, 1:22 PM PDT	Excessive Heat Watch	SGX	24 hr
May 3, 1:22 PM PDT	Heat Advisory	SGX	5 days
May 4, 1:20 PM PDT	Excessive Heat Warning	SGX	4 days
May 4, 1:55 PM PDT	Excessive Heat Watch	PSR	13 hr
May 5, 2:36 AM PDT	Excessive Heat Warning	PSR	65 hr
May 11, 1:28 PM PDT	Wind Advisory	SGX	40 hr
May 17, 12:41 PM PDT	Wind Advisory	SGX	44 hr
May 21, 1:34 PM PDT	Excessive Heat Watch	SGX	61 hr
May 22, 3:32 AM PDT	Excessive Heat Watch	PSR	47 hr
May 24, 2:54 AM PDT	Excessive Heat Warning	SGX	6 days
May 24, 2:55 AM PDT	Excessive Heat Warning	PSR	8 days
Jun 1, 2:36 AM PDT	Excessive Heat Watch	PSR	23 hr
Jun 1, 12:39 PM PDT	Excessive Heat Watch	SGX	24 hr
Jun 2, 2:04 AM PDT	Excessive Heat Warning	PSR	66 hr
Jun 2, 12:50 PM PDT	Excessive Heat Warning	SGX	54 hr
Jun 4, 1:30 PM PDT	Wind Advisory	SGX	3 days
Jun 4, 2:33 PM PDT	Wind Advisory	PSR	62 hr
Jun 7, 2:35 AM PDT	Wind Advisory	SGX	36 hr
Jun 10, 2:59 AM PDT	Heat Advisory	SGX	16 hr
Jun 27, 1:00 PM PDT	Wind Advisory	SGX	43 hr
Jun 27, 2:04 PM PDT	Wind Advisory	PSR	41 hr
Jul 6, 2:31 PM PDT	Excessive Heat Watch	PSR	48 hr
Jul 7, 3:33 AM PDT	Excessive Heat Watch	SGX	34 hr
Jul 8, 1:42 PM PDT	Excessive Heat Warning	SGX	5 days
Jul 8, 2:19 PM PDT	Excessive Heat Warning	PSR	5 days
Jul 9, 1:29 PM PDT	Heat Advisory	SGX	3 days
Jul 19, 8:47 AM PDT	Wind Advisory	SGX	21 hr
Jul 27, 1:17 AM PDT	Excessive Heat Watch	PSR	26 hr
Jul 27, 3:26 AM PDT	Excessive Heat Watch	SGX	33 hr
Jul 28, 2:57 AM PDT	Excessive Heat Warning	PSR	8 days
Jul 28, 12:36 PM PDT	Excessive Heat Warning	SGX	5 days
Jul 29, 2:19 AM PDT	Heat Advisory	SGX	4 days
Aug 10, 2:20 AM PDT	Excessive Heat Watch	PSR	35 hr
Aug 11, 12:38 PM PDT	Excessive Heat Watch	SGX	25 hr
Aug 11, 1:27 PM PDT	Excessive Heat Warning	PSR	9 days
Aug 12, 1:39 PM PDT	Excessive Heat Warning	SGX	9 days
Aug 15, 2:24 PM PDT	Severe Thunderstorm Warning	SGX	55 min
Aug 15, 2:32 PM PDT	Special Weather Statement	PSR	43 min
Aug 15, 3:24 PM PDT	Flash Flood Warning Considerable damage threat	PSR	4 hr
Aug 15, 3:46 PM PDT	Special Weather Statement	PSR	44 min
Aug 15, 4:08 PM PDT	Severe Thunderstorm Warning	PSR	37 min
Aug 15, 4:38 PM PDT	Flash Flood Warning Considerable damage threat	PSR	4 hr
Aug 18, 12:28 PM PDT	Severe Thunderstorm Warning	SGX	46 min
Aug 18, 12:50 PM PDT	Flash Flood Warning	SGX	3 hr
Aug 18, 12:57 PM PDT	Special Weather Statement	PSR	48 min
Aug 18, 2:10 PM PDT	Flash Flood Warning	SGX	59 min
Aug 18, 3:12 PM PDT	Severe Thunderstorm Warning	SGX	21 min
Aug 18, 5:49 PM PDT	Special Weather Statement	PSR	56 min
Aug 21, 1:21 PM PDT	Severe Thunderstorm Warning	SGX	26 min
Aug 23, 2:25 AM PDT	Excessive Heat Warning	PSR	6 days
Aug 24, 1:17 PM PDT	Excessive Heat Watch	SGX	14 hr
Aug 24, 1:17 PM PDT	Heat Advisory	SGX	4 days
Aug 25, 3:43 AM PDT	Excessive Heat Warning	SGX	4 days
Aug 28, 1:48 AM PDT	Excessive Heat Warning	PSR	18 hr
Sep 1, 2:23 AM PDT	Excessive Heat Watch	PSR	35 hr
Sep 1, 2:44 AM PDT	Excessive Heat Watch	SGX	33 hr
Sep 2, 12:12 PM PDT	Excessive Heat Warning	SGX	5 days
Sep 2, 1:33 PM PDT	Excessive Heat Warning	PSR	5 days
Sep 3, 1:16 PM PDT	Fire Weather Watch	SGX	21 hr
Sep 4, 10:15 AM PDT	Red Flag Warning	SGX	56 hr
Sep 6, 2:09 PM PDT	Fire Weather Watch	SGX	23 hr
Sep 6, 2:44 PM PDT	Red Flag Warning	PSR	57 hr
Sep 6, 2:44 PM PDT	Wind Advisory	PSR	55 hr
Sep 7, 1:09 PM PDT	Red Flag Warning	SGX	55 hr
Sep 8, 11:58 AM PDT	Blowing Dust Advisory	PSR	4 hr
Sep 9, 10:15 AM PDT	Red Flag Warning	PSR	7 hr
Sep 25, 1:52 PM PDT	Fire Weather Watch	SGX	47 hr
Sep 27, 1:03 PM PDT	Red Flag Warning	SGX	52 hr
Sep 27, 1:10 PM PDT	Heat Advisory	SGX	4 days
Sep 30, 1:30 PM PDT	Excessive Heat Warning	SGX	55 hr
Sep 30, 1:30 PM PDT	Heat Advisory	SGX	55 hr
Oct 11, 12:32 PM PDT	Heat Advisory	SGX	5 days
Oct 14, 12:40 PM PDT	Fire Weather Watch	SGX	21 hr
Oct 15, 10:00 AM PDT	Red Flag Warning	SGX	32 hr
Oct 23, 1:26 PM PDT	Fire Weather Watch	SGX	24 hr
Oct 23, 1:38 PM PDT	High Wind Watch	SGX	24 hr
Oct 24, 1:40 PM PDT	Red Flag Warning	SGX	3 days
Oct 24, 1:55 PM PDT	High Wind Warning	SGX	3 days
Oct 24, 1:55 PM PDT	Wind Advisory	SGX	51 hr
Oct 24, 1:59 PM PDT	Wind Advisory	PSR	55 hr
Oct 24, 2:03 PM PDT	Fire Weather Watch	PSR	24 hr
Oct 25, 3:06 AM PDT	Wind Advisory	SGX	19 hr
Oct 25, 9:33 AM PDT	Blowing Dust Advisory	PSR	7 hr
Oct 25, 2:17 PM PDT	Red Flag Warning	PSR	31 hr
Oct 25, 2:26 PM PDT	High Wind Warning	PSR	27 hr
Oct 26, 4:02 AM PDT	Blowing Dust Advisory	PSR	13 hr
Oct 26, 10:05 AM PDT	Wind Advisory	PSR	7 hr
Oct 26, 9:07 PM PDT	Red Flag Warning	PSR	17 hr
Nov 5, 1:37 PM PST	Wind Advisory	SGX	3 days
Nov 5, 8:35 PM PST	Winter Weather Advisory	SGX	16 hr
Nov 6, 1:22 AM PST	Wind Advisory	PSR	66 hr
Nov 6, 12:46 PM PST	Winter Storm Warning	SGX	57 hr
Nov 6, 1:12 PM PST	Flash Flood Watch	SGX	31 hr
Nov 7, 8:55 AM PST	Blowing Dust Advisory	PSR	8 hr
Nov 7, 9:37 AM PST	Flash Flood Warning Considerable damage threat	SGX	38 min
Nov 9, 3:23 AM PST	Frost Advisory	SGX	5 hr
Nov 9, 3:23 AM PST	Frost Advisory	SGX	29 hr
Nov 24, 1:26 PM PST	Fire Weather Watch	SGX	24 hr
Nov 25, 1:25 PM PST	Red Flag Warning	SGX	68 hr
Nov 26, 10:02 AM PST	High Wind Warning	SGX	27 hr
Nov 30, 12:50 PM PST	Fire Weather Watch	SGX	23 hr
Dec 1, 12:11 PM PST	Red Flag Warning	SGX	71 hr
Dec 1, 12:12 PM PST	High Wind Watch	SGX	15 hr
Dec 2, 1:01 AM PST	Freeze Watch	PSR	24 hr
Dec 2, 2:45 AM PST	High Wind Warning	SGX	39 hr
Dec 3, 12:44 AM PST	Freeze Warning	PSR	30 hr
Dec 3, 12:21 PM PST	Freeze Warning	PSR	43 hr
Dec 4, 1:07 PM PST	Fire Weather Watch	SGX	24 hr
Dec 5, 12:59 PM PST	Red Flag Warning	SGX	3 days
Dec 6, 1:11 PM PST	High Wind Watch	SGX	15 hr
Dec 7, 4:30 AM PST	High Wind Warning	SGX	33 hr
Dec 12, 1:27 AM PST	Wind Advisory	SGX	15 hr
Dec 21, 1:08 PM PST	Fire Weather Watch	SGX	21 hr
Dec 22, 9:55 AM PST	Red Flag Warning	SGX	50 hr
Dec 26, 3:10 AM PST	Winter Storm Watch	SGX	24 hr
Dec 27, 3:08 AM PST	Winter Storm Warning	SGX	48 hr
Dec 28, 1:22 AM PST	Areal Flood Advisory	SGX	3 hr
Dec 28, 1:17 PM PST	Areal Flood Advisory	SGX	3 hr
Dec 28, 4:08 PM PST	Areal Flood Advisory	SGX	4 hr
Dec 28, 6:11 PM PST	Areal Flood Advisory	SGX	4 hr
Dec 31, 2:53 AM PST	Wind Advisory	SGX	33 hr

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

Product	Alerts
Severe storms
Severe Thunderstorm Warning	5
Special Weather Statement	5
Flooding
Flash Flood Warning	15
Flash Flood Watch	5
Areal Flood Advisory	17
Winter
Winter Storm Warning	3
Winter Storm Watch	3
Winter Weather Advisory	8
Heat
Excessive Heat Warning	21
Excessive Heat Watch	16
Heat Advisory	9
Cold
Freeze Warning	4
Freeze Watch	3
Frost Advisory	2
Wind and dust
High Wind Warning	10
High Wind Watch	8
Blowing Dust Advisory	4
Wind Advisory	31
Fire
Red Flag Warning	13
Fire Weather Watch	10
Fog and smoke
Dense Fog Advisory	1

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2019 2021

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.