Severe Thunderstorm Warning for Rock and Walworth Counties, WI

Source: NOAA · Southern Wisconsin

This alert is no longer in effect.

NOAA issued it on August 11, 2026, 12 days 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.

NWS Milwaukee/Sullivan has issued a Severe Thunderstorm Warning for southwestern Walworth County and southeastern Rock County until 3:30 AM CDT August 11.

Read this weather record in 30 seconds

Record type
Severe Thunderstorm Warning
Affected area
Southern Wisconsin
Issued
August 11, 2026
Issuing authority
NWS Milwaukee/Sullivan WI

Storm notices can cover different combinations of wind, hail, lightning, and rainfall. Use the original notice for the hazards and boundaries attached to this specific record.

Record status: historical. It was issued 12 days ago; use the issuing agency's live warning service for current conditions in Southern Wisconsin.

Alert Details

Severe Thunderstorm Warning issued by NWS Milwaukee/Sullivan WI. Effective from 2026-08-11T03:02:00-05:00 until 2026-08-11T03:30:00-05:00. Alert type code: SVR.

Affected Areas

Southwestern Walworth County in southeastern Wisconsin and southeastern Rock County in south central Wisconsin. Locations impacted include Delavan, Williams Bay, Walworth, Clinton, Fontana-On-Geneva Lake, Sharon, Darien, Tiffany, Allens Grove, Avalon, Shopiere, Emerald Grove, Foxhollow, and Delavan Lake.

What You Should Do

For your protection move to an interior room on the lowest floor of a building.

Expected Conditions

At 3:02 AM CDT, a severe thunderstorm was located over Clinton, or 10 miles east of Beloit, moving southeast at 25 mph. Hazards include 60 mph wind gusts and quarter size hail (1.00 inch). Radar indicated. Hail damage to vehicles is expected. Expect wind damage to roofs, siding, and trees.

Timeline

The warning is effective immediately from 3:02 AM CDT and expires at 3:30 AM CDT on August 11, 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?
NWS Milwaukee/Sullivan has issued a Severe Thunderstorm Warning for southwestern Walworth County and southeastern Rock County until 3:30 AM CDT August 11.
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 Southern 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.