Alert archive / California / Tehama County

Weather alerts in Tehama County, California, 2012

22 weather alerts in 2012, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Tehama County and its neighbors

Each county as a circle sized by its count in 2012. Tap one for its archive.

Alerts
22
Warnings
10
Watches
0
Advisories
6
Busiest month
December7 alerts
Busiest day
December 2, 20125 alerts

Over time

By month

Warning verification

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

Tehama County, 2012

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings3167%450%24 min
Flash flood warnings110%2100%62 min

Each office's whole area, 2012

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Sacramento, CA: tornado warnings8275%1429%28 min
NWS Sacramento, CA: severe thunderstorm warnings6183%729%24 min
NWS Sacramento, CA: flash flood warnings110%1020%62 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.

IssuedProductOfficeLasted
Jan 20, 7:35 PM PSTAreal Flood AdvisorySTO6 hr
Feb 13, 1:04 AM PSTAreal Flood AdvisorySTO89 min
Mar 11, 2:29 PM PDTSpecial Weather StatementSTO46 min
Apr 12, 11:11 AM PDTMesoscale DiscussionSPC64 min
Apr 12, 3:08 PM PDTMesoscale DiscussionSPC97 min
Apr 13, 9:11 AM PDTAreal Flood AdvisorySTO4 hr
May 3, 8:13 PM PDTFlash Flood WarningSTO107 min
Jun 4, 4:32 PM PDTSevere Thunderstorm WarningSTO43 min
Jun 4, 5:50 PM PDTSevere Thunderstorm WarningSTO55 min
Jun 4, 6:46 PM PDTSevere Thunderstorm WarningSTO59 min
Oct 22, 1:42 PM PDTSpecial Weather StatementSTO48 min
Oct 22, 1:48 PM PDTMesoscale DiscussionSPC117 min
Nov 29, 2:29 PM PSTRiver Flood WarningSTO6 hr
Nov 29, 3:23 PM PSTAreal Flood WarningSTO14 hr
Nov 30, 5:29 AM PSTAreal Flood AdvisorySTO12 hr
Dec 1, 2:10 PM PSTRiver Flood WarningSTO37 hr
Dec 1, 10:38 PM PSTAreal Flood AdvisorySTO12 hr
Dec 1, 10:46 PM PSTAreal Flood AdvisorySTO12 hr
Dec 2, 4:23 AM PSTAreal Flood WarningSTO6 hr
Dec 2, 9:06 AM PSTRiver Flood WarningSTO18 hr
Dec 2, 10:01 AM PSTAreal Flood WarningSTO21 hr
Dec 23, 3:43 PM PSTSpecial Weather StatementSTO62 min

By product

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

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20112013

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.