Alert archive / California / Sierra County

Weather alerts in Sierra County, California, 2018

58 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Sierra County and its neighbors

Each county as a circle sized by its count in 2018. Tap one for its archive.

Alerts: 58
Warnings: 12
Watches: 20
Advisories: 22
Busiest month: August9 alerts
Busiest day: July 23, 20183 alerts

Over time

By month

Warning verification

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

Sierra County, 2018

	Warnings	With a report	False alarm ratio
Tornado warnings	0
Severe thunderstorm warnings	0
Flash flood warnings	1	0	100%

Each office's whole area, 2018

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Reno, NV: severe thunderstorm warnings	18	0	100%	1	0%
NWS Reno, NV: flash flood warnings	19	5	74%	13	46%	57 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 15, 2:32 PM PST	Winter Storm Watch	REV	48 hr
Jan 17, 2:32 PM PST	Winter Weather Advisory	REV	41 hr
Jan 22, 3:06 PM PST	Winter Weather Advisory	REV	3 days
Feb 21, 3:25 AM PST	Winter Weather Advisory	REV	43 hr
Feb 24, 1:58 PM PST	Winter Weather Advisory	REV	65 hr
Feb 27, 3:30 AM PST	Winter Storm Watch	REV	23 hr
Feb 27, 2:12 PM PST	Winter Storm Warning	REV	4 days
Mar 12, 2:54 AM PDT	Winter Weather Advisory	REV	67 hr
Mar 13, 3:28 AM PDT	Winter Storm Watch	REV	47 hr
Mar 13, 4:45 PM PDT	Winter Storm Warning	REV	3 days
Mar 20, 2:24 PM PDT	Flood Watch	REV	48 hr
Mar 22, 5:56 AM PDT	Winter Weather Advisory	REV	11 hr
Mar 22, 2:11 PM PDT	Winter Weather Advisory	REV	63 hr
Apr 3, 9:12 AM PDT	Flood Watch	REV	4 days
Apr 5, 3:06 PM PDT	Wind Advisory	REV	53 hr
Apr 7, 7:15 AM PDT	Areal Flood Advisory	STO	6 hr
Apr 9, 2:36 AM PDT	Wind Advisory	REV	68 hr
Apr 11, 2:23 AM PDT	Winter Weather Advisory	REV	25 hr
Apr 14, 4:23 AM PDT	Wind Advisory	REV	46 hr
May 24, 4:03 PM PDT	Special Weather Statement	STO	42 min
May 25, 2:52 AM PDT	Flood Watch	REV	12 hr
May 29, 12:26 PM PDT	Lake Wind Advisory	REV	33 hr
Jun 2, 3:22 PM PDT	Lake Wind Advisory	REV	55 hr
Jun 7, 1:42 PM PDT	Lake Wind Advisory	REV	57 hr
Jun 24, 2:35 PM PDT	Lake Wind Advisory	REV	31 hr
Jul 12, 5:28 PM PDT	Special Weather Statement	REV	62 min
Jul 12, 5:53 PM PDT	Special Weather Statement	REV	37 min
Jul 14, 6:04 PM PDT	Special Weather Statement	REV	41 min
Jul 22, 5:07 PM PDT	Areal Flood Advisory	REV	113 min
Jul 23, 3:10 AM PDT	Flash Flood Watch	REV	18 hr
Jul 23, 4:01 PM PDT	Flash Flood Warning	REV	3 hr
Aug 1, 1:07 PM PDT	Fire Weather Watch	REV	22 hr
Aug 2, 11:00 AM PDT	Red Flag Warning	REV	59 hr
Aug 2, 1:31 PM PDT	Lake Wind Advisory	REV	56 hr
Aug 3, 1:18 PM PDT	Dense Smoke Advisory	REV	41 hr
Aug 8, 8:16 AM PDT	Fire Weather Watch	REV	43 hr
Aug 10, 2:59 AM PDT	Fire Weather Watch	REV	7 hr
Aug 10, 9:31 AM PDT	Red Flag Warning	REV	35 hr
Aug 12, 5:21 AM PDT	Fire Weather Watch	REV	34 hr
Aug 23, 12:19 PM PDT	Fire Weather Watch	REV	50 hr
Sep 9, 3:01 PM PDT	Fire Weather Watch	REV	20 hr
Sep 10, 11:10 AM PDT	Red Flag Warning	REV	66 hr
Sep 26, 2:47 PM PDT	Fire Weather Watch	REV	38 hr
Sep 28, 5:10 AM PDT	Red Flag Warning	REV	39 hr
Oct 11, 1:40 PM PDT	Freeze Watch	REV	24 hr
Oct 12, 1:24 PM PDT	Freeze Warning	REV	68 hr
Oct 25, 1:57 PM PDT	Fire Weather Watch	REV	45 hr
Oct 27, 11:11 AM PDT	Red Flag Warning	REV	35 hr
Nov 21, 3:37 AM PST	High Wind Watch	REV	25 hr
Nov 21, 3:37 AM PST	Wind Advisory	REV	63 hr
Nov 22, 4:34 AM PST	High Wind Warning	REV	34 hr
Nov 28, 2:50 PM PST	Winter Storm Watch	REV	23 hr
Nov 29, 1:57 PM PST	Winter Storm Warning	REV	49 hr
Dec 4, 10:02 AM PST	Winter Weather Advisory	REV	24 hr
Dec 13, 3:23 AM PST	High Wind Watch	REV	11 hr
Dec 13, 2:42 PM PST	High Wind Warning	REV	29 hr
Dec 21, 2:17 PM PST	Winter Storm Watch	REV	36 hr
Dec 23, 2:45 AM PST	Winter Weather Advisory	REV	50 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	4
Flooding
Flash Flood Warning	1
Flash Flood Watch	1
Flood Watch	3
Areal Flood Advisory	2
Winter
Winter Storm Warning	3
Winter Storm Watch	5
Winter Weather Advisory	10
Cold
Freeze Warning	1
Freeze Watch	1
Wind and dust
High Wind Warning	2
High Wind Watch	2
Lake Wind Advisory	5
Wind Advisory	4
Fire
Red Flag Warning	5
Fire Weather Watch	8
Fog and smoke
Dense Smoke 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 2017 2019

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.