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

Source: NOAA · Southeast Wisconsin

This alert is no longer in effect.

NOAA issued it on April 26, 2026, 3 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 Flood Warning is in effect for Jefferson, Rock, and Walworth counties in Wisconsin until 12:15 AM CDT on April 18, 2026, due to excessive rainfall causing flooding.

Read this weather record in 30 seconds

Record type
Flood Warning
Affected area
Southeast Wisconsin
Issued
April 26, 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 3 months ago; use the issuing agency's live warning service for current conditions in Southeast Wisconsin.

Flood Warning in Wisconsin

Alert Details

A Flood Warning has been issued by NWS Milwaukee/Sullivan WI. It is effective from 9:21 PM CDT on April 17, 2026, until 12:15 AM CDT on April 18, 2026.

Affected Areas

The warning affects Jefferson, WI; Rock, WI; and Walworth, WI. 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

Flooding caused by excessive rainfall is expected. Between 2 and 4 inches of rain have fallen. Flooding of rivers, creeks, streams, and other low-lying and flood-prone locations is imminent or occurring.

Timeline

The alert is effective from 9:21 PM CDT on April 17, 2026, and ends at 12:15 AM CDT on April 18, 2026.

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 Flood Warning is in effect for Jefferson, Rock, and Walworth counties in Wisconsin until 12:15 AM CDT on April 18, 2026, due to excessive rainfall causing flooding.
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 Southeast 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.