Alert archive / California / Placer County

Weather alerts in Placer County, California, 2010

151 weather alerts in 2010, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Placer County and its neighbors

Each county as a circle sized by its count in 2010. Tap one for its archive.

Alerts: 151
Warnings: 18
Watches: 19
Advisories: 105
Busiest month: December21 alerts
Busiest day: January 19, 20105 alerts

Over time

By month

Warning verification

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

Placer County, 2010

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

Each office's whole area, 2010

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Phoenix, AZ: tornado warnings	4	2	50%	3	67%	9 min
NWS Phoenix, AZ: severe thunderstorm warnings	82	36	56%	113	69%	19 min
NWS Phoenix, AZ: flash flood warnings	38	11	71%	18	89%	36 min
NWS Sacramento, CA: tornado warnings	0			3	0%
NWS Sacramento, CA: severe thunderstorm warnings	4	0	100%	1	0%
NWS San Diego, CA: tornado warnings	4	2	50%	2	100%	15 min
NWS San Diego, CA: severe thunderstorm warnings	15	4	73%	18	33%	29 min
NWS San Diego, CA: flash flood warnings	29	9	69%	24	46%	84 min
NWS Las Vegas, NV: tornado warnings	0			2	0%
NWS Las Vegas, NV: severe thunderstorm warnings	66	6	91%	43	35%	15 min
NWS Las Vegas, NV: flash flood warnings	90	30	67%	87	48%	98 min
NWS San Francisco Bay Area, CA: tornado warnings	3	0	100%	0
NWS San Francisco Bay Area, CA: severe thunderstorm warnings	6	0	100%	9	0%
NWS San Francisco Bay Area, CA: flash flood warnings	2	0	100%	1	0%
NWS Los Angeles, CA: tornado warnings	1	0	100%	3	0%
NWS Los Angeles, CA: severe thunderstorm warnings	16	3	81%	35	14%	42 min
NWS Los Angeles, CA: flash flood warnings	30	2	93%	21	10%	112 min
NWS Hanford, CA: tornado warnings	1	1	0%	2	50%	0 min
NWS Hanford, CA: severe thunderstorm warnings	6	0	100%	12	0%
NWS Hanford, CA: flash flood warnings	6	0	100%	3	0%
NWS Medford, OR: severe thunderstorm warnings	23	10	57%	17	82%	15 min
NWS Medford, OR: flash flood warnings	1	0	100%	0
NWS Reno, NV: severe thunderstorm warnings	26	2	92%	8	38%	18 min
NWS Reno, NV: flash flood warnings	19	2	89%	3	67%	20 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 9, 3:42 PM PST	Freezing Fog Advisory	REV	21 hr
Jan 11, 3:29 PM PST	Lake Wind Advisory	REV	27 hr
Jan 11, 3:37 PM PST	Winter Weather Advisory	REV	42 hr
Jan 12, 4:34 PM PST	Mesoscale Discussion	SPC	4 hr
Jan 13, 12:17 AM PST	Mesoscale Discussion	SPC	4 hr
Jan 15, 3:00 PM PST	Winter Storm Watch	REV	24 hr
Jan 16, 2:59 PM PST	Winter Storm Warning	REV	58 hr
Jan 19, 2:21 AM PST	Winter Storm Watch	REV	25 hr
Jan 19, 2:21 AM PST	Winter Weather Advisory	REV	20 hr
Jan 19, 5:52 AM PST	Areal Flood Advisory	STO	8 hr
Jan 19, 1:57 PM PST	Areal Flood Advisory	STO	2 hr
Jan 19, 3:34 PM PST	Winter Storm Warning	REV	60 hr
Jan 20, 8:10 AM PST	Areal Flood Advisory	STO	12 hr
Jan 21, 3:06 AM PST	Winter Weather Advisory	REV	25 hr
Jan 21, 9:28 PM PST	Areal Flood Advisory	STO	4 hr
Jan 24, 3:14 PM PST	Winter Weather Advisory	REV	37 hr
Jan 25, 1:16 PM PST	Areal Flood Advisory	STO	12 hr
Feb 4, 2:32 PM PST	Winter Weather Advisory	REV	22 hr
Feb 22, 2:23 PM PST	Winter Weather Advisory	REV	44 hr
Feb 24, 2:42 PM PST	Winter Storm Watch	REV	25 hr
Feb 25, 2:44 PM PST	Winter Weather Advisory	REV	42 hr
Mar 1, 2:12 PM PST	Lake Wind Advisory	REV	38 hr
Mar 2, 2:17 PM PST	Winter Weather Advisory	REV	36 hr
Mar 7, 2:32 PM PST	Lake Wind Advisory	REV	28 hr
Mar 11, 2:48 PM PST	Winter Weather Advisory	REV	37 hr
Mar 11, 2:50 PM PST	Lake Wind Advisory	REV	30 hr
Mar 17, 3:28 PM PDT	Lake Wind Advisory	REV	29 hr
Mar 21, 2:48 AM PDT	Lake Wind Advisory	REV	17 hr
Mar 24, 3:16 AM PDT	Lake Wind Advisory	REV	12 hr
Mar 24, 3:03 PM PDT	Wind Advisory	REV	16 hr
Mar 25, 3:57 AM PDT	Lake Wind Advisory	REV	14 hr
Mar 27, 1:22 PM PDT	High Wind Watch	REV	23 hr
Mar 27, 1:22 PM PDT	Lake Wind Advisory	REV	46 hr
Mar 28, 3:57 AM PDT	High Wind Warning	REV	59 hr
Mar 28, 11:58 AM PDT	Blizzard Watch	REV	23 hr
Mar 29, 11:12 AM PDT	Winter Storm Warning	REV	36 hr
Mar 31, 4:39 AM PDT	Winter Weather Advisory	REV	6 hr
Apr 1, 3:36 PM PDT	Wind Advisory	REV	31 hr
Apr 3, 2:26 PM PDT	Lake Wind Advisory	REV	30 hr
Apr 3, 2:49 PM PDT	Winter Storm Watch	REV	13 hr
Apr 4, 3:51 AM PDT	Winter Storm Warning	REV	29 hr
Apr 4, 9:37 PM PDT	Areal Flood Advisory	STO	3 hr
Apr 9, 3:13 PM PDT	Lake Wind Advisory	REV	28 hr
Apr 10, 2:52 PM PDT	Lake Wind Advisory	REV	25 hr
Apr 10, 2:56 PM PDT	Winter Weather Advisory	REV	31 hr
Apr 12, 2:37 AM PDT	Lake Wind Advisory	REV	13 hr
Apr 18, 2:01 PM PDT	Lake Wind Advisory	REV	49 hr
Apr 26, 4:16 AM PDT	High Wind Warning	REV	42 hr
Apr 26, 4:16 AM PDT	Lake Wind Advisory	REV	22 hr
Apr 26, 4:16 AM PDT	Wind Advisory	REV	34 hr
Apr 26, 2:39 PM PDT	Winter Weather Advisory	REV	32 hr
Apr 27, 10:44 PM PDT	Lake Wind Advisory	REV	21 hr
Apr 28, 4:17 PM PDT	Special Weather Statement	STO	43 min
Apr 28, 5:33 PM PDT	Winter Weather Advisory	REV	5 hr
May 2, 2:18 PM PDT	Lake Wind Advisory	REV	30 hr
May 4, 3:31 PM PDT	Lake Wind Advisory	REV	28 hr
May 8, 3:31 PM PDT	Lake Wind Advisory	REV	28 hr
May 9, 3:16 PM PDT	Lake Wind Advisory	REV	29 hr
May 10, 4:26 AM PDT	Winter Weather Advisory	REV	19 hr
May 16, 2:11 PM PDT	Lake Wind Advisory	REV	25 hr
May 18, 3:00 PM PDT	Lake Wind Advisory	REV	29 hr
May 20, 1:50 PM PDT	Lake Wind Advisory	REV	33 hr
May 22, 2:56 PM PDT	Winter Weather Advisory	REV	18 hr
May 30, 3:21 PM PDT	Lake Wind Advisory	REV	29 hr
Jun 2, 2:47 PM PDT	Lake Wind Advisory	REV	30 hr
Jun 3, 2:42 PM PDT	Lake Wind Advisory	REV	30 hr
Jun 5, 3:24 PM PDT	Lake Wind Advisory	REV	29 hr
Jun 8, 2:08 PM PDT	Lake Wind Advisory	REV	31 hr
Jun 10, 5:53 AM PDT	Lake Wind Advisory	REV	14 hr
Jun 11, 3:26 AM PDT	Lake Wind Advisory	REV	34 hr
Jun 18, 2:53 PM PDT	Lake Wind Advisory	REV	31 hr
Jun 29, 3:41 PM PDT	Lake Wind Advisory	REV	28 hr
Jul 4, 1:06 PM PDT	Lake Wind Advisory	REV	3 hr
Jul 8, 2:05 PM PDT	Special Weather Statement	STO	55 min
Jul 16, 6:28 AM PDT	Flash Flood Watch	REV	14 hr
Jul 23, 9:31 AM PDT	Fire Weather Watch	REV	32 hr
Jul 24, 9:21 AM PDT	Red Flag Warning	REV	57 hr
Jul 30, 3:33 PM PDT	Lake Wind Advisory	REV	29 hr
Aug 8, 8:15 AM PDT	Flash Flood Watch	REV	13 hr
Aug 11, 9:40 AM PDT	Lake Wind Advisory	REV	8 hr
Aug 15, 3:12 PM PDT	Fire Weather Watch	REV	39 hr
Aug 16, 9:36 AM PDT	Red Flag Warning	REV	39 hr
Aug 16, 2:57 PM PDT	Lake Wind Advisory	REV	34 hr
Aug 18, 3:32 AM PDT	Lake Wind Advisory	REV	15 hr
Aug 19, 9:35 AM PDT	Fire Weather Watch	REV	22 hr
Aug 20, 7:40 AM PDT	Red Flag Warning	REV	39 hr
Aug 20, 8:21 AM PDT	Lake Wind Advisory	REV	52 hr
Aug 23, 9:12 PM PDT	Lake Wind Advisory	REV	9 hr
Aug 24, 11:01 AM PDT	Fire Weather Watch	REV	52 hr
Aug 25, 10:36 AM PDT	Red Flag Warning	REV	37 hr
Aug 25, 3:38 PM PDT	Lake Wind Advisory	REV	29 hr
Aug 26, 10:15 AM PDT	Red Flag Warning	REV	53 hr
Aug 26, 9:01 PM PDT	Lake Wind Advisory	REV	50 hr
Sep 2, 1:00 PM PDT	Fire Weather Watch	REV	22 hr
Sep 4, 3:41 PM PDT	Lake Wind Advisory	REV	42 hr
Sep 6, 1:46 PM PDT	Red Flag Warning	REV	33 hr
Sep 6, 3:16 PM PDT	Lake Wind Advisory	REV	56 hr
Sep 18, 3:00 AM PDT	Lake Wind Advisory	REV	42 hr
Oct 4, 3:15 AM PDT	Winter Weather Advisory	REV	38 hr
Oct 4, 4:19 AM PDT	Areal Flood Advisory	REV	4 hr
Oct 4, 5:14 AM PDT	Areal Flood Advisory	STO	4 hr
Oct 11, 1:26 PM PDT	Lake Wind Advisory	REV	13 hr
Oct 18, 4:05 PM PDT	Lake Wind Advisory	REV	16 hr
Oct 22, 2:46 PM PDT	High Wind Watch	REV	20 hr
Oct 22, 2:46 PM PDT	Lake Wind Advisory	REV	20 hr
Oct 23, 10:47 AM PDT	Wind Advisory	REV	41 hr
Oct 24, 9:23 AM PDT	Areal Flood Advisory	REV	12 hr
Oct 24, 10:09 AM PDT	Areal Flood Advisory	STO	6 hr
Oct 24, 12:49 PM PDT	Areal Flood Advisory	REV	8 hr
Oct 24, 3:36 PM PDT	Areal Flood Warning	REV	5 hr
Oct 24, 4:01 PM PDT	Areal Flood Advisory	STO	3 hr
Oct 24, 5:47 PM PDT	Areal Flood Warning	REV	3 hr
Oct 30, 1:21 PM PDT	Lake Wind Advisory	REV	6 hr
Nov 6, 2:36 PM PDT	Winter Weather Advisory	REV	37 hr
Nov 6, 2:48 PM PDT	Lake Wind Advisory	REV	27 hr
Nov 9, 9:34 PM PST	Lake Wind Advisory	REV	12 hr
Nov 10, 3:09 PM PST	Lake Wind Advisory	REV	19 hr
Nov 12, 2:37 PM PST	Lake Wind Advisory	REV	18 hr
Nov 13, 9:57 PM PST	Lake Wind Advisory	REV	10 hr
Nov 14, 1:49 PM PST	Lake Wind Advisory	REV	16 hr
Nov 17, 3:12 PM PST	Lake Wind Advisory	REV	28 hr
Nov 17, 3:12 PM PST	Wind Advisory	REV	49 hr
Nov 17, 3:37 PM PST	Winter Storm Watch	REV	23 hr
Nov 18, 3:00 PM PST	Winter Storm Warning	REV	3 days
Nov 20, 8:39 PM PST	Mesoscale Discussion	SPC	4 hr
Nov 21, 3:09 AM PST	Winter Storm Watch	REV	34 hr
Nov 21, 3:33 PM PST	Winter Weather Advisory	REV	18 hr
Nov 21, 9:13 PM PST	Lake Wind Advisory	REV	25 hr
Nov 22, 5:02 AM PST	Winter Storm Warning	REV	35 hr
Nov 26, 2:40 AM PST	Winter Weather Advisory	REV	49 hr
Dec 2, 3:52 AM PST	Wind Advisory	REV	18 hr
Dec 5, 3:45 AM PST	Winter Weather Advisory	REV	27 hr
Dec 6, 3:34 AM PST	Lake Wind Advisory	REV	6 hr
Dec 7, 12:43 PM PST	Lake Wind Advisory	REV	27 hr
Dec 9, 9:34 PM PST	Lake Wind Advisory	REV	18 hr
Dec 12, 3:16 PM PST	Winter Storm Watch	REV	24 hr
Dec 13, 3:11 PM PST	Winter Weather Advisory	REV	34 hr
Dec 15, 3:33 PM PST	Winter Storm Watch	REV	25 hr
Dec 16, 4:08 PM PST	Winter Storm Warning	REV	4 days
Dec 17, 1:54 PM PST	Areal Flood Advisory	STO	48 hr
Dec 19, 9:08 AM PST	Mesoscale Discussion	SPC	5 hr
Dec 19, 1:59 PM PST	Areal Flood Advisory	STO	12 hr
Dec 19, 3:32 PM PST	Special Weather Statement	STO	43 min
Dec 19, 3:36 PM PST	Special Weather Statement	STO	39 min
Dec 23, 3:59 AM PST	Freezing Fog Advisory	REV	8 hr
Dec 25, 4:00 AM PST	Winter Weather Advisory	REV	24 hr
Dec 25, 9:10 AM PST	Lake Wind Advisory	REV	10 hr
Dec 27, 4:03 AM PST	Winter Storm Watch	REV	18 hr
Dec 27, 9:51 PM PST	Winter Storm Warning	REV	41 hr
Dec 28, 1:22 PM PST	Areal Flood Advisory	STO	14 hr
Dec 28, 4:58 PM PST	Mesoscale Discussion	SPC	6 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
Mesoscale Discussion	5
Special Weather Statement	4
Flooding
Areal Flood Warning	2
Flash Flood Watch	2
Areal Flood Advisory	15
Winter
Winter Storm Warning	8
Blizzard Watch	1
Winter Storm Watch	9
Winter Weather Advisory	22
Wind and dust
High Wind Warning	2
High Wind Watch	2
Lake Wind Advisory	60
Wind Advisory	6
Fire
Red Flag Warning	6
Fire Weather Watch	5
Fog and smoke
Freezing Fog Advisory	2

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2009 2011

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.