Flood Warning Issued for Jefferson and Rock Counties, 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This alert is no longer in effect.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 and Rock Counties in Wisconsin, with major flooding expected on the Rock River starting Saturday morning.
Read this weather record in 30 seconds
- Record type
- Flood Warning
- Affected area
- Jefferson and Rock Counties, Wisconsin
- Issued
- April 26, 2026
- Issuing authority
- NWS Milwaukee
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 Jefferson and Rock Counties, Wisconsin.
Alert Details
The National Weather Service (NWS) Milwaukee/Sullivan WI has issued a Flood Warning. This alert is effective from April 17, 2026, at 10:08 PM CDT, with onset on April 18, 2026, at 7:00 AM CDT.
Affected Areas
The warning affects Jefferson and Rock Counties in Wisconsin, specifically the Rock River near Lake Koshkonong.
What You Should Do
Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. Additional information is available at www.weather.gov.
Expected Conditions
Major flooding is forecast. The river stage was 9.7 feet at 9:00 PM CDT on April 17, 2026, with bankfull stage at 9.0 feet and flood stage at 10.0 feet. The river is expected to rise above flood stage and reach 12.1 feet on Thursday morning.
Timeline
The alert is effective from April 18, 2026, at 7:00 AM CDT and expires on April 18, 2026, at 10:15 AM CDT, but may continue until further notice as indicated.
Original source: NOAA Official Notice ↗
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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.
Similar body length
Nearest notices by article body length (952 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to April 26, 2026.
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