Flash Flood Warning Issued for Jefferson, Rock, and Walworth Counties in Wisconsin

Source: NOAA · Southeastern Wisconsin

This alert is no longer in effect.

NOAA issued it on April 25, 2026, 4 months ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).

Areazine synthesizes this NWS weather alert directly from NOAA's official public data feed. See our methodology for full source attribution and refresh cadence.

A Flash Flood Warning is in effect for Jefferson, Rock, and Walworth counties in Wisconsin until 10:15 PM CDT, with heavy rain causing potential flooding in urban areas and low-lying regions.

Read this weather record in 30 seconds

Record type
Flash Flood Warning
Affected area
Southeastern Wisconsin
Issued
April 25, 2026
Issuing authority
NWS Milwaukee Sullivan WI

Flood notices turn on location and timing. Treat the named area as this record's scope; do not assume nearby counties, parishes, or waterways were included.

Record status: historical. It was issued 4 months ago; use the issuing agency's live warning service for current conditions in Southeastern Wisconsin.

Alert Details

The National Weather Service in Milwaukee/Sullivan WI has issued a Flash Flood Warning. This alert is effective from 7:01 PM CDT on April 17, 2026.

Affected Areas

The warning affects Jefferson County, Rock County, and Walworth County in Wisconsin. Specific locations include Whitewater, Palmyra, Lake Koshkonong, Richmond, La Grange, Hebron, Millard, and Lima Center.

What You Should Do

Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles.

Expected Conditions

Doppler radar indicated thunderstorms producing heavy rain across the warned area. Between 1.5 and 2.5 inches of rain have fallen, with additional rainfall amounts of 0.5 to 1.5 inches possible. Flash flooding is ongoing or expected, affecting small creeks and streams, urban areas, highways, streets, underpasses, and other poor drainage and low-lying areas.

Timeline

The alert is effective from 7:01 PM CDT on April 17, 2026, and expires at 10:15 PM CDT on the same day.

Original source: NOAA Official Notice ↗

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Nationwide notices with similar length or severity timing 8

Two Areazine-derived peer sets for this NWS weather alert: nearest notices by body length and by same severity near the same agency date. Peers come from other categories so they are not the same-feed Related list above.

Frequently Asked Questions

Common questions about this NWS weather alert.

What is this NWS weather alert about?
A Flash Flood Warning is in effect for Jefferson, Rock, and Walworth counties in Wisconsin until 10:15 PM CDT, with heavy rain causing potential flooding in urban areas and low-lying regions.
Which agency issued this alert?
This alert was issued by NOAA. The original notice is available at the source link at the bottom of this article.
How severe is this alert?
This alert is classified as "high" severity. Take precautions and monitor for updates.
What area is affected?
This alert affects Southeastern Wisconsin. Check with NOAA for the most current geographic scope.
Where can I find more Weather Alerts updates?
Browse the full Weather Alerts feed on Areazine at areazine.com/weather/ for the latest updates from NOAA and other agencies.