Alert archive / Iowa / Wayne County / Flash Flood Warnings

Flash Flood Warnings in Wayne County, Iowa, 2010

7 flash flood warnings in 2010. An alert counts here when it covered this county. The archive of flash flood warnings reaches back to 1986.

Wayne County and its neighbors

Each county as a circle sized by its count in 2010. Tap one for its archive.

Flash Flood Warnings
7
Busiest month
July2 flash flood warnings
Busiest day
June 15, 20101 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.

6 of 7 flash flood warnings covering Wayne County in 2010 had a flash flood report inside them; 4 of 4 flash flood reports fell inside a warning, on average 253 minutes after it went out.

Wayne County, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Flash flood warnings7614%4100%253 min

Each office's whole area, 2010

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Des Moines, IA: flash flood warnings1006436%18087%120 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, Central Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jun 15, 9:05 AM CDTFlash Flood WarningDMX6 hr
Jul 4, 9:17 PM CDTFlash Flood WarningDMX6 hr
Jul 20, 12:50 AM CDTFlash Flood WarningDMX6 hr
Aug 13, 2:06 PM CDTFlash Flood WarningDMX6 hr
Aug 13, 8:01 PM CDTFlash Flood WarningDMX2 hr
Sep 19, 2:17 AM CDTFlash Flood WarningDMX5 hr
Sep 21, 4:26 PM CDTFlash Flood WarningDMX5 hr

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20092011

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.