Alert archive / Arizona / Pima County / Flash Flood Warnings

Flash Flood Warnings in Pima County, Arizona, 2015

30 flash flood warnings in 2015. An alert counts here when it covered this county. The archive of flash flood warnings reaches back to 1986.

Pima County and its neighbors

Each county as a circle sized by its count in 2015. Tap one for its archive.

Flash Flood Warnings
30
Busiest month
August14 flash flood warnings
Busiest day
July 29, 20154 flash flood warnings

Over time

By month

Warning verification

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

3 of 30 flash flood warnings covering Pima County in 2015 had a flash flood report inside them; 3 of 5 flash flood reports fell inside a warning, on average 63 minutes after it went out.

Pima County, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Flash flood warnings30390%560%63 min

Each office's whole area, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Tucson, AZ: flash flood warnings51688%1060%43 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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jul 5, 2:14 PM MSTFlash Flood WarningTWC2 hr
Jul 16, 7:17 PM MSTFlash Flood WarningTWC118 min
Jul 17, 6:06 PM MSTFlash Flood WarningTWC114 min
Jul 17, 7:34 PM MSTFlash Flood WarningTWC116 min
Jul 17, 8:00 PM MSTFlash Flood WarningTWC3 hr
Jul 28, 4:53 PM MSTFlash Flood WarningTWC82 min
Jul 28, 5:02 PM MSTFlash Flood WarningTWC118 min
Jul 28, 5:26 PM MSTFlash Flood WarningTWC109 min
Jul 28, 5:40 PM MSTFlash Flood WarningTWC2 hr
Jul 28, 6:28 PM MSTFlash Flood WarningTWC2 hr
Aug 1, 3:58 PM MSTFlash Flood WarningTWC92 min
Aug 7, 11:16 AM MSTFlash Flood WarningTWC119 min
Aug 7, 1:08 PM MSTFlash Flood WarningTWC97 min
Aug 7, 2:40 PM MSTFlash Flood WarningTWC3 hr
Aug 7, 3:53 PM MSTFlash Flood WarningTWC3 hr
Aug 7, 10:44 PM MSTFlash Flood WarningTWC3 hr
Aug 9, 5:32 PM MSTFlash Flood WarningTWC118 min
Aug 11, 6:31 PM MSTFlash Flood WarningTWC89 min
Aug 11, 7:59 PM MSTFlash Flood WarningTWC2 hr
Aug 20, 3:48 PM MSTFlash Flood WarningTWC87 min
Aug 20, 4:25 PM MSTFlash Flood WarningTWC3 hr
Aug 22, 3:55 PM MSTFlash Flood WarningTWC2 hr
Aug 22, 3:56 PM MSTFlash Flood WarningTWC2 hr
Aug 22, 4:32 PM MSTFlash Flood WarningTWC118 min
Sep 1, 12:58 AM MSTFlash Flood WarningTWC3 hr
Sep 3, 12:09 PM MSTFlash Flood WarningTWC81 min
Sep 21, 12:10 PM MSTFlash Flood WarningTWC3 hr
Sep 21, 1:27 PM MSTFlash Flood WarningTWC3 hr
Sep 21, 3:35 PM MSTFlash Flood WarningTWC4 hr
Oct 16, 4:34 PM MSTFlash Flood WarningTWC116 min

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20142016

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.