Alert archive / Arizona / Maricopa County / Flash Flood Warnings

Flash Flood Warnings in Maricopa County, Arizona, 2014

38 flash flood warnings in 2014. An alert counts here when it covered this county. The archive of flash flood warnings reaches back to 1986.

Maricopa County and its neighbors

Each county as a circle sized by its count in 2014. Tap one for its archive.

Flash Flood Warnings
38
Busiest month
August22 flash flood warnings
Busiest day
August 19, 20148 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.

10 of 38 flash flood warnings covering Maricopa County in 2014 had a flash flood report inside them; 19 of 26 flash flood reports fell inside a warning, on average 36 minutes after it went out.

Maricopa County, 2014

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Flash flood warnings381074%2673%36 min

Each office's whole area, 2014

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Phoenix, AZ: flash flood warnings661577%3669%39 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
Mar 1, 4:59 PM MSTFlash Flood WarningPSR2 hr
Jul 5, 7:04 PM MSTFlash Flood WarningPSR3 hr
Jul 6, 3:32 PM MSTFlash Flood WarningPSR118 min
Jul 13, 4:53 PM MSTFlash Flood WarningPSR112 min
Jul 13, 5:28 PM MSTFlash Flood WarningPSR2 hr
Jul 15, 3:06 PM MSTFlash Flood WarningPSR114 min
Jul 31, 8:36 PM MSTFlash Flood WarningPSR114 min
Jul 31, 8:56 PM MSTFlash Flood WarningPSR79 min
Jul 31, 10:13 PM MSTFlash Flood WarningPSR3 hr
Jul 31, 10:58 PM MSTFlash Flood WarningPSR3 hr
Aug 2, 4:39 PM MSTFlash Flood WarningPSR3 hr
Aug 2, 4:41 PM MSTFlash Flood WarningPSR2 hr
Aug 2, 5:14 PM MSTFlash Flood WarningPSR2 hr
Aug 3, 4:30 PM MSTFlash Flood WarningPSR2 hr
Aug 3, 5:34 PM MSTFlash Flood WarningPSR86 min
Aug 12, 4:26 PM MSTFlash Flood WarningPSR2 hr
Aug 12, 5:14 PM MSTFlash Flood WarningPSR2 hr
Aug 12, 5:45 PM MSTFlash Flood WarningPSR2 hr
Aug 12, 6:14 PM MSTFlash Flood WarningPSR2 hr
Aug 19, 7:08 AM MSTFlash Flood WarningPSR112 min
Aug 19, 9:03 AM MSTFlash Flood WarningPSR117 min
Aug 19, 11:05 AM MSTFlash Flood WarningPSR115 min
Aug 19, 12:11 PM MSTFlash Flood WarningPSR2 hr
Aug 19, 1:07 PM MSTFlash Flood WarningPSR113 min
Aug 19, 3:02 PM MSTFlash Flood WarningPSR118 min
Aug 19, 4:17 PM MSTFlash Flood WarningPSR3 hr
Aug 19, 4:53 PM MSTFlash Flood WarningPSR112 min
Aug 25, 11:00 PM MSTFlash Flood WarningPSR3 hr
Sep 6, 7:00 PM MSTFlash Flood WarningPSR2 hr
Sep 8, 1:17 AM MSTFlash Flood WarningPSR3 hr
Sep 8, 2:56 AM MSTFlash Flood WarningPSR109 min
Sep 8, 4:27 AM MSTFlash Flood WarningPSR2 hr
Sep 8, 5:02 AM MSTFlash Flood WarningPSR118 min
Sep 8, 6:27 AM MSTFlash Flood WarningPSR4 hr
Sep 8, 7:59 AM MSTFlash Flood WarningPSR2 hr
Sep 17, 12:36 PM MSTFlash Flood WarningPSR114 min
Sep 27, 3:29 PM MSTFlash Flood WarningPSR3 hr
Sep 27, 5:42 PM MSTFlash Flood WarningPSR2 hr

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20132015

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.