Alert archive / California / Imperial County

Weather alerts in Imperial County, California, 2011

48 weather alerts in 2011, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Imperial County and its neighbors

Each county as a circle sized by its count in 2011. Tap one for its archive.

Alerts
48
Warnings
19
Watches
7
Advisories
6
Busiest month
July16 alerts
Busiest day
July 6, 20116 alerts

Over time

By month

Warning verification

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

Imperial County, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings9456%989%19 min
Flash flood warnings10100%10%

Each office's whole area, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Phoenix, AZ: tornado warnings10100%0
NWS Phoenix, AZ: severe thunderstorm warnings762666%7163%18 min
NWS Phoenix, AZ: flash flood warnings7186%250%34 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
Feb 1, 1:08 PM PSTRed Flag WarningPSR29 hr
Feb 19, 4:57 AM PSTAreal Flood AdvisoryPSR108 min
Feb 19, 7:33 AM PSTAreal Flood AdvisoryPSR117 min
Apr 27, 2:42 PM PDTFire Weather WatchPSR39 hr
Apr 28, 4:56 AM PDTFire Weather WatchPSR10 hr
Apr 28, 4:56 AM PDTRed Flag WarningPSR39 hr
Apr 28, 2:34 PM PDTRed Flag WarningPSR52 hr
May 6, 5:30 AM PDTFire Weather WatchPSR32 hr
May 7, 1:15 PM PDTRed Flag WarningPSR31 hr
May 23, 5:21 AM PDTRed Flag WarningPSR15 hr
May 26, 2:40 PM PDTFire Weather WatchPSR24 hr
May 26, 2:40 PM PDTFire Weather WatchPSR60 hr
May 27, 2:32 PM PDTRed Flag WarningPSR29 hr
May 28, 2:55 PM PDTRed Flag WarningPSR29 hr
Jul 3, 12:17 AM PDTSpecial Weather StatementPSR58 min
Jul 3, 12:47 AM PDTSpecial Weather StatementPSR88 min
Jul 3, 5:24 PM PDTSevere Thunderstorm WatchSPC7 hr
Jul 3, 7:26 PM PDTMesoscale DiscussionSPC2 hr
Jul 5, 5:19 PM PDTSpecial Weather StatementPSR41 min
Jul 5, 5:36 PM PDTMesoscale DiscussionSPC54 min
Jul 5, 9:28 PM PDTMesoscale DiscussionSPC2 hr
Jul 5, 10:41 PM PDTSevere Thunderstorm WarningPSR40 min
Jul 6, 12:45 PM PDTMesoscale DiscussionSPC3 hr
Jul 6, 4:40 PM PDTFlash Flood WarningPSR65 min
Jul 7, 4:46 PM PDTSpecial Weather StatementPSR44 min
Jul 7, 4:55 PM PDTSevere Thunderstorm WarningPSR50 min
Jul 7, 5:11 PM PDTAreal Flood AdvisoryPSR2 hr
Jul 7, 5:30 PM PDTSpecial Weather StatementPSR60 min
Jul 7, 5:47 PM PDTSpecial Weather StatementPSR43 min
Jul 10, 5:37 PM PDTSevere Thunderstorm WarningPSR53 min
Aug 27, 10:02 PM PDTSevere Thunderstorm WarningPSR58 min
Aug 27, 11:59 PM PDTSpecial Weather StatementPSR46 min
Sep 5, 3:57 PM PDTAreal Flood AdvisoryPSR2 hr
Sep 5, 4:19 PM PDTSevere Thunderstorm WarningPSR41 min
Sep 10, 1:58 AM PDTAreal Flood AdvisoryPSR2 hr
Sep 13, 10:00 AM PDTSevere Thunderstorm WarningPSR60 min
Sep 13, 1:21 PM PDTSevere Thunderstorm WarningPSR54 min
Sep 13, 2:12 PM PDTSevere Thunderstorm WarningPSR63 min
Sep 13, 3:15 PM PDTSpecial Weather StatementPSR45 min
Sep 13, 3:56 PM PDTMesoscale DiscussionSPC94 min
Sep 13, 4:54 PM PDTSpecial Weather StatementPSR21 min
Oct 3, 2:45 PM PDTSpecial Weather StatementPSR45 min
Oct 3, 2:53 PM PDTSevere Thunderstorm WarningPSR37 min
Oct 3, 3:31 PM PDTSpecial Weather StatementPSR44 min
Oct 25, 2:41 PM PDTRed Flag WarningPSR30 hr
Oct 31, 3:05 PM PDTFire Weather WatchPSR24 hr
Nov 1, 2:42 PM PDTRed Flag WarningPSR24 hr
Dec 13, 5:28 PM PSTAreal Flood AdvisoryPSR107 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 archive20102012

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.