Alert archive / Wisconsin / Flash Flood Warnings

Flash Flood Warnings in Wisconsin, 2023

13 flash flood warnings in 2023. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of flash flood warnings reaches back to 1986.

Flash Flood Warnings by county

Each county as a circle sized by its count in 2023. Tap one for its archive.

Flash Flood Warnings
13
Busiest month
July8 flash flood warnings
Busiest day
July 28, 20234 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.

4 of 13 flash flood warnings covering Wisconsin in 2023 had a flash flood report inside them; 8 of 10 flash flood reports fell inside a warning, on average 56 minutes after it went out.

Wisconsin, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Flash flood warnings13469%1080%56 min

Each office's whole area, 2023

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Duluth, MN: flash flood warnings6350%1560%44 min
NWS La Crosse, WI: flash flood warnings2150%1100%152 min
NWS Milwaukee, WI: flash flood warnings7271%667%23 min
NWS Twin Cities, MN: flash flood warnings5180%475%168 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.

IssuedProductOfficeCountiesLasted
Apr 19, 2:13 PM CDTFlash Flood WarningMKXColumbia, Dane, Sauk3 hr
Apr 19, 4:00 PM CDTFlash Flood WarningMKXDodge, Ozaukee, Washington3 hr
Jul 3, 7:34 PM CDTFlash Flood WarningMPXSaint Croix101 min
Jul 27, 5:06 PM CDTFlash Flood WarningDLHBayfield, Douglas, Sawyer, Washburn4 hr
Jul 27, 7:31 PM CDTFlash Flood WarningDLHPrice4 hr
Jul 27, 7:48 PM CDTFlash Flood WarningDLHBurnett, Washburn4 hr
Jul 27, 7:53 PM CDTFlash Flood WarningMPXBarron, Rusk3 hr
Jul 27, 8:09 PM CDTFlash Flood WarningMPXPolk3 hr
Jul 28, 8:49 PM CDTFlash Flood WarningMKXGreen, Iowa, Lafayette4 hr
Jul 28, 10:25 PM CDTFlash Flood WarningMKXDane2 hr
Aug 14, 4:29 PM CDTFlash Flood WarningMKXKenosha, Racine2 hr
Aug 24, 6:01 PM CDTFlash Flood WarningMKXRacine2 hr
Sep 26, 9:37 PM CDTFlash Flood WarningMKXLafayette3 hr

By county

Every county with at least one alert. A county page lists each alert that covered it.

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordThe radar archive20222024

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.