Alert archive / California / Orange County

Weather alerts in Orange County, California, 2009

44 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Orange County and its neighbors

Each county as a circle sized by its count in 2009. Tap one for its archive.

Alerts
44
Warnings
11
Watches
11
Advisories
20
Busiest month
November9 alerts
Busiest day
November 24, 20094 alerts

Over time

By month

Warning verification

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

Orange County, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings10100%0
Flash flood warnings00

Each office's whole area, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS San Diego, CA: severe thunderstorm warnings9189%250%46 min
NWS San Diego, CA: flash flood warnings7357%944%40 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 7, 1:01 PM PSTHigh Wind WatchSGX24 hr
Jan 8, 1:08 PM PSTHigh Wind WarningSGX5 days
Jan 8, 1:08 PM PSTWind AdvisorySGX5 days
Jan 27, 7:11 AM PSTWind AdvisorySGX8 hr
Jan 28, 1:13 PM PSTHigh Wind WatchSGX6 hr
Jan 28, 1:13 PM PSTWind AdvisorySGX52 hr
Jan 28, 7:38 PM PSTHigh Wind WarningSGX42 hr
Feb 6, 12:10 PM PSTMesoscale DiscussionSPC3 hr
Feb 6, 1:37 PM PSTFlash Flood WatchSGX26 hr
Feb 8, 8:10 PM PSTWind AdvisorySGX28 hr
Feb 15, 1:30 PM PSTWind AdvisorySGX26 hr
Feb 15, 1:31 PM PSTFlash Flood WatchSGX28 hr
Feb 16, 8:51 AM PSTMesoscale DiscussionSPC84 min
Feb 16, 10:18 AM PSTAreal Flood AdvisorySGX8 hr
Mar 21, 5:59 PM PDTWind AdvisorySGX33 hr
Mar 26, 1:11 PM PDTHigh Wind WarningSGX24 hr
Apr 3, 6:46 AM PDTDense Fog AdvisorySGX4 hr
Apr 14, 3:06 AM PDTWind AdvisorySGX22 hr
Jun 10, 1:26 PM PDTDense Fog AdvisorySGX22 hr
Jun 13, 12:02 AM PDTDense Fog AdvisorySGX10 hr
Sep 2, 4:19 PM PDTSevere Thunderstorm WarningSGX26 min
Sep 20, 1:39 PM PDTFire Weather WatchSGX24 hr
Sep 21, 1:36 PM PDTRed Flag WarningSGX3 days
Sep 29, 1:42 PM PDTFire Weather WatchSGX24 hr
Sep 30, 1:29 PM PDTRed Flag WarningSGX29 hr
Oct 27, 2:59 AM PDTWind AdvisorySGX37 hr
Oct 27, 9:56 AM PDTFire Weather WatchSGX17 hr
Oct 27, 9:56 AM PDTRed Flag WarningSGX30 hr
Nov 5, 4:39 AM PSTDense Fog AdvisorySGX3 hr
Nov 13, 2:18 PM PSTFire Weather WatchSGX23 hr
Nov 14, 1:36 PM PSTRed Flag WarningSGX26 hr
Nov 14, 1:50 PM PSTWind AdvisorySGX28 hr
Nov 23, 9:31 PM PSTWind AdvisorySGX25 min
Nov 23, 9:56 PM PSTHigh Wind WarningSGX5 hr
Nov 24, 3:03 AM PSTWind AdvisorySGX9 hr
Nov 24, 10:01 AM PSTRed Flag WarningSGX48 hr
Nov 28, 1:26 PM PSTWind AdvisorySGX48 hr
Dec 6, 11:16 AM PSTHigh Wind WatchSGX16 hr
Dec 6, 7:09 PM PSTFlash Flood WatchSGX25 hr
Dec 7, 2:54 AM PSTHigh Wind WarningSGX27 hr
Dec 7, 7:57 AM PSTWind AdvisorySGX19 hr
Dec 12, 5:59 PM PSTFlash Flood WatchSGX15 hr
Dec 22, 2:56 AM PSTWind AdvisorySGX10 hr
Dec 22, 9:13 PM PSTWind AdvisorySGX13 hr

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 archive20082010

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.