Alert archive / California / Alameda County

Weather alerts in Alameda County, California, 2023

150 weather alerts in 2023, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Alameda County and its neighbors

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

Alerts: 150
Warnings: 22
Watches: 15
Advisories: 83
Busiest month: January51 alerts
Busiest day: January 10, 202311 alerts

Over time

By month

Warning verification

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

Alameda County, 2023

	Reports	Inside a warning
Tornado warnings	0
Severe thunderstorm warnings	1	0%
Flash flood warnings	0

Each office's whole area, 2023

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Hanford, CA: tornado warnings	6	0	100%	1	0%
NWS Hanford, CA: severe thunderstorm warnings	24	2	92%	41	24%	15 min
NWS Hanford, CA: flash flood warnings	60	8	87%	59	20%	193 min
NWS Las Vegas, NV: tornado warnings	1	0	100%	0
NWS Las Vegas, NV: severe thunderstorm warnings	52	6	88%	37	22%	21 min
NWS Las Vegas, NV: flash flood warnings	146	56	62%	184	68%	114 min
NWS San Francisco Bay Area, CA: severe thunderstorm warnings	3	2	33%	58	12%	23 min
NWS San Francisco Bay Area, CA: flash flood warnings	11	1	91%	8	13%	172 min
NWS Sacramento, CA: tornado warnings	3	1	67%	4	25%	27 min
NWS Sacramento, CA: severe thunderstorm warnings	24	6	75%	39	56%	18 min
NWS Sacramento, CA: flash flood warnings	8	4	50%	24	33%	38 min
NWS Eureka, CA: tornado warnings	0			1	0%
NWS Eureka, CA: severe thunderstorm warnings	3	0	100%	0
NWS Eureka, CA: flash flood warnings	4	0	100%	18	0%
NWS Los Angeles, CA: tornado warnings	4	0	100%	8	0%
NWS Los Angeles, CA: severe thunderstorm warnings	1	0	100%	5	0%
NWS Los Angeles, CA: flash flood warnings	30	22	27%	190	73%	210 min
NWS Medford, OR: severe thunderstorm warnings	12	1	92%	3	33%	6 min
NWS Medford, OR: flash flood warnings	6	2	67%	3	67%	37 min
NWS San Diego, CA: tornado warnings	2	0	100%	0
NWS San Diego, CA: severe thunderstorm warnings	9	0	100%	12	0%
NWS San Diego, CA: flash flood warnings	19	8	58%	89	13%	141 min
NWS Phoenix, AZ: severe thunderstorm warnings	87	23	74%	71	77%	21 min
NWS Phoenix, AZ: flash flood warnings	47	21	55%	50	88%	96 min
NWS Reno, NV: severe thunderstorm warnings	18	1	94%	8	13%	21 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	Lasted
Jan 2, 12:09 PM PST	Flood Watch	MTR	3 days
Jan 2, 12:27 PM PST	High Wind Watch	MTR	21 hr
Jan 3, 9:45 AM PST	High Wind Warning	MTR	40 hr
Jan 4, 4:54 PM PST	Areal Flood Advisory	MTR	42 min
Jan 4, 5:36 PM PST	Areal Flood Warning	MTR	9 hr
Jan 5, 2:06 AM PST	Wind Advisory	MTR	8 hr
Jan 5, 8:56 AM PST	Areal Flood Advisory	MTR	6 hr
Jan 5, 10:38 AM PST	Areal Flood Warning	MTR	8 hr
Jan 6, 3:16 AM PST	Flood Watch	MTR	5 days
Jan 6, 1:09 PM PST	Wind Advisory	MTR	40 hr
Jan 8, 11:31 AM PST	High Wind Warning	MTR	22 hr
Jan 9, 6:59 AM PST	Areal Flood Advisory	MTR	12 hr
Jan 9, 12:06 PM PST	Wind Advisory	MTR	25 hr
Jan 10, 12:55 AM PST	Areal Flood Advisory	MTR	3 hr
Jan 10, 2:17 AM PST	Special Weather Statement	MTR	28 min
Jan 10, 2:50 AM PST	Special Weather Statement	MTR	10 min
Jan 10, 7:07 AM PST	Special Weather Statement	MTR	38 min
Jan 10, 7:44 AM PST	Special Weather Statement	MTR	31 min
Jan 10, 7:55 AM PST	Special Weather Statement	MTR	35 min
Jan 10, 8:30 AM PST	Special Weather Statement	MTR	30 min
Jan 10, 8:34 AM PST	Special Weather Statement	MTR	26 min
Jan 10, 9:38 AM PST	Special Weather Statement	MTR	37 min
Jan 10, 10:21 AM PST	Special Weather Statement	MTR	39 min
Jan 10, 12:26 PM PST	Areal Flood Warning	MTR	3 hr
Jan 10, 7:13 PM PST	Special Weather Statement	MTR	32 min
Jan 10, 8:13 PM PST	Special Weather Statement	MTR	32 min
Jan 11, 2:04 AM PST	Wind Advisory	MTR	17 hr
Jan 11, 3:25 PM PST	Areal Flood Advisory	MTR	6 hr
Jan 12, 10:04 AM PST	Flood Watch	MTR	4 days
Jan 12, 7:37 PM PST	Wind Advisory	MTR	14 hr
Jan 13, 12:32 PM PST	Coastal Flood Advisory	MTR	68 hr
Jan 13, 12:41 PM PST	Wind Advisory	MTR	25 hr
Jan 14, 11:11 AM PST	Areal Flood Warning	MTR	16 hr
Jan 15, 3:05 AM PST	Wind Advisory	MTR	30 hr
Jan 16, 1:41 AM PST	Areal Flood Advisory	MTR	6 hr
Jan 16, 2:43 AM PST	Areal Flood Warning	MTR	15 hr
Jan 16, 2:56 AM PST	Areal Flood Warning	MTR	15 hr
Jan 16, 11:20 AM PST	Areal Flood Advisory	MTR	3 hr
Jan 16, 8:39 PM PST	Coastal Flood Advisory	MTR	15 hr
Jan 17, 9:41 PM PST	Coastal Flood Advisory	MTR	6 days
Jan 18, 6:56 PM PST	Freeze Warning	MTR	34 hr
Jan 19, 2:16 PM PST	Freeze Warning	MTR	43 hr
Jan 21, 1:41 PM PST	Wind Advisory	MTR	35 hr
Jan 27, 1:13 PM PST	Freeze Watch	MTR	24 hr
Jan 28, 5:04 AM PST	Dense Fog Advisory	MTR	6 hr
Jan 28, 12:47 PM PST	Frost Advisory	MTR	44 hr
Jan 28, 12:47 PM PST	Freeze Warning	MTR	39 hr
Jan 29, 1:05 PM PST	Freeze Watch	MTR	15 hr
Jan 30, 4:13 AM PST	Frost Advisory	MTR	29 hr
Jan 30, 4:13 AM PST	Freeze Warning	MTR	29 hr
Jan 31, 2:03 AM PST	Frost Advisory	MTR	31 hr
Feb 3, 10:28 PM PST	Dense Fog Advisory	MTR	7 hr
Feb 13, 1:38 AM PST	Freeze Watch	MTR	25 hr
Feb 14, 2:25 AM PST	Frost Advisory	MTR	31 hr
Feb 14, 2:25 AM PST	Freeze Warning	MTR	31 hr
Feb 14, 12:34 PM PST	Freeze Watch	MTR	20 hr
Feb 15, 9:02 AM PST	Frost Advisory	MTR	24 hr
Feb 19, 4:30 PM PST	Wind Advisory	MTR	69 hr
Feb 21, 2:42 AM PST	Frost Advisory	MTR	54 hr
Feb 21, 2:42 AM PST	Freeze Watch	MTR	24 hr
Feb 22, 2:45 AM PST	Winter Storm Watch	MTR	13 hr
Feb 22, 2:46 AM PST	Freeze Warning	MTR	30 hr
Feb 22, 12:55 PM PST	Wind Advisory	MTR	44 hr
Feb 22, 3:39 PM PST	Winter Storm Warning	MTR	45 hr
Feb 22, 7:01 PM PST	Special Weather Statement	MTR	29 min
Feb 23, 3:35 AM PST	Frost Advisory	MTR	24 hr
Feb 23, 3:35 AM PST	Freeze Warning	MTR	24 hr
Feb 24, 3:08 AM PST	Frost Advisory	MTR	27 hr
Feb 26, 12:54 PM PST	Winter Weather Advisory	MTR	63 hr
Feb 27, 9:30 AM PST	Special Weather Statement	MTR	15 min
Feb 27, 9:44 AM PST	Special Weather Statement	MTR	31 min
Feb 27, 9:47 AM PST	Special Weather Statement	MTR	13 min
Feb 27, 10:01 AM PST	Special Weather Statement	MTR	14 min
Feb 27, 1:17 PM PST	Special Weather Statement	MTR	43 min
Feb 27, 3:22 PM PST	Special Weather Statement	MTR	53 min
Feb 27, 4:04 PM PST	Special Weather Statement	MTR	56 min
Feb 27, 8:35 PM PST	Special Weather Statement	MTR	40 min
Feb 28, 12:53 PM PST	Areal Flood Advisory	MTR	3 hr
Feb 28, 1:09 PM PST	Frost Advisory	MTR	19 hr
Feb 28, 1:09 PM PST	Freeze Warning	MTR	19 hr
Mar 1, 12:07 PM PST	Frost Advisory	MTR	21 hr
Mar 1, 12:07 PM PST	Freeze Warning	MTR	21 hr
Mar 3, 1:00 PM PST	Winter Weather Advisory	MTR	48 hr
Mar 4, 11:03 AM PST	Special Weather Statement	MTR	42 min
Mar 4, 11:24 AM PST	Special Weather Statement	MTR	51 min
Mar 5, 2:20 AM PST	Special Weather Statement	MTR	55 min
Mar 5, 10:39 AM PST	Special Weather Statement	MTR	51 min
Mar 5, 9:28 PM PST	Winter Weather Advisory	MTR	13 hr
Mar 6, 4:20 PM PST	Special Weather Statement	MTR	25 min
Mar 7, 12:21 PM PST	Flood Watch	MTR	4 days
Mar 8, 3:54 AM PST	Wind Advisory	MTR	53 hr
Mar 10, 12:17 AM PST	Areal Flood Advisory	MTR	21 hr
Mar 11, 11:30 AM PST	Flood Watch	MTR	3 days
Mar 11, 11:36 AM PST	High Wind Watch	MTR	23 hr
Mar 11, 4:54 PM PST	Special Weather Statement	MTR	36 min
Mar 12, 9:34 AM PDT	Areal Flood Advisory	MTR	11 hr
Mar 12, 11:32 AM PDT	High Wind Warning	MTR	57 hr
Mar 12, 11:48 AM PDT	Areal Flood Warning	MTR	9 hr
Mar 19, 2:23 PM PDT	Wind Advisory	MTR	55 hr
Mar 21, 8:20 AM PDT	Areal Flood Advisory	MTR	55 min
Mar 21, 3:57 PM PDT	Areal Flood Advisory	MTR	20 hr
Mar 21, 4:43 PM PDT	Areal Flood Advisory	MTR	6 hr
Mar 21, 5:10 PM PDT	Special Weather Statement	MTR	50 min
Mar 21, 7:19 PM PDT	Coastal Flood Advisory	MTR	9 hr
Mar 22, 8:33 AM PDT	Coastal Flood Advisory	MTR	18 hr
Mar 23, 2:12 AM PDT	Frost Advisory	MTR	4 days
Mar 26, 2:15 PM PDT	Wind Advisory	MTR	52 hr
Mar 28, 9:46 AM PDT	Areal Flood Advisory	MTR	6 hr
Mar 29, 12:48 PM PDT	Areal Flood Advisory	MTR	3 hr
Mar 29, 1:35 PM PDT	Special Weather Statement	MTR	25 min
Mar 29, 2:05 PM PDT	Special Weather Statement	MTR	25 min
Mar 29, 2:25 PM PDT	Areal Flood Advisory	MTR	2 hr
Jun 27, 12:06 PM PDT	Heat Advisory	MTR	5 days
Jul 10, 1:07 PM PDT	Excessive Heat Watch	MTR	49 hr
Jul 12, 1:37 PM PDT	Excessive Heat Warning	MTR	4 days
Jul 19, 11:30 AM PDT	Heat Advisory	MTR	3 days
Aug 14, 5:29 PM PDT	Special Weather Statement	MTR	31 min
Oct 4, 12:50 PM PDT	Heat Advisory	MTR	3 days
Oct 17, 1:27 PM PDT	Heat Advisory	MTR	56 hr
Oct 26, 10:40 AM PDT	Fire Weather Watch	MTR	23 hr
Oct 27, 1:25 AM PDT	Wind Advisory	MTR	61 hr
Oct 27, 10:01 AM PDT	Red Flag Warning	MTR	55 hr
Nov 19, 2:07 PM PST	Wind Advisory	MTR	22 hr
Nov 25, 7:11 AM PST	Coastal Flood Advisory	MTR	3 hr
Nov 25, 5:18 PM PST	Coastal Flood Advisory	MTR	19 hr
Nov 26, 11:39 AM PST	Coastal Flood Advisory	MTR	25 hr
Nov 27, 8:52 AM PST	Frost Advisory	MTR	24 hr
Nov 27, 12:39 PM PST	Coastal Flood Advisory	MTR	24 hr
Dec 4, 5:56 PM PST	Dense Fog Advisory	MTR	17 hr
Dec 5, 8:20 PM PST	Dense Fog Advisory	MTR	12 hr
Dec 12, 8:39 AM PST	Coastal Flood Advisory	MTR	4 hr
Dec 12, 2:11 PM PST	Coastal Flood Advisory	MTR	23 hr
Dec 12, 8:44 PM PST	Dense Fog Advisory	MTR	14 hr
Dec 13, 1:10 PM PST	Coastal Flood Advisory	MTR	25 hr
Dec 14, 1:47 PM PST	Coastal Flood Advisory	MTR	24 hr
Dec 18, 5:33 AM PST	Areal Flood Advisory	MTR	3 hr
Dec 19, 2:15 PM PST	Coastal Flood Advisory	MTR	17 hr
Dec 20, 6:46 AM PST	Areal Flood Advisory	MTR	119 min
Dec 20, 8:54 AM PST	Areal Flood Advisory	MTR	2 hr
Dec 20, 12:05 PM PST	Coastal Flood Advisory	MTR	21 hr
Dec 21, 12:38 PM PST	Coastal Flood Advisory	MTR	21 hr
Dec 22, 11:13 AM PST	Coastal Flood Advisory	MTR	23 hr
Dec 23, 9:45 AM PST	Coastal Flood Advisory	MTR	25 hr
Dec 24, 10:40 AM PST	Coastal Flood Advisory	MTR	24 hr
Dec 25, 10:50 AM PST	Coastal Flood Advisory	MTR	26 hr
Dec 26, 12:16 PM PST	Coastal Flood Advisory	MTR	44 hr
Dec 27, 1:16 PM PST	Coastal Flood Advisory	MTR	104 min
Dec 27, 1:16 PM PST	Coastal Flood Advisory	MTR	24 hr
Dec 28, 1:35 PM PST	Wind Advisory	MTR	29 hr
Dec 29, 4:31 PM PST	Areal Flood Advisory	MTR	5 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
Special Weather Statement	30
Flooding
Areal Flood Warning	7
Flood Watch	5
Areal Flood Advisory	20
Winter
Winter Storm Warning	1
Winter Storm Watch	1
Winter Weather Advisory	3
Heat
Excessive Heat Warning	1
Excessive Heat Watch	1
Heat Advisory	4
Cold
Freeze Warning	9
Freeze Watch	5
Frost Advisory	12
Wind and dust
High Wind Warning	3
High Wind Watch	2
Wind Advisory	16
Fire
Red Flag Warning	1
Fire Weather Watch	1
Fog and smoke
Dense Fog Advisory	5
Coast and beach
Coastal Flood Advisory	23

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast 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.