Severe Thunderstorms Cause Destruction Across Illinois and Wisconsin

Severe thunderstorms with destructive winds swept through parts of Illinois and Wisconsin on Wednesday afternoon. The storms left more than 200,000 people without power and prompted urgent warnings from the National Weather Service (NWS).

The storms are part of a broader multiday severe weather outbreak affecting the Midwest. Forecasters warned of widespread dangerous thunderstorms expected through Thursday. AccuWeather reported that more than 200 million people could be impacted, including major cities like Chicago, Milwaukee, and Green Bay, which face the risk of repeated rounds of storms.

Meteorologists highlighted primary threats, including wind gusts up to 100 mph, large hail, possible tornadoes, and heavy rainfall leading to flash flooding.

Wisconsin and Illinois Under Severe Thunderstorm Alerts

Nearing late Wednesday afternoon, nearly all of Wisconsin and much of Illinois were under severe thunderstorm warnings or watches. An NWS warning issued in Green Bay at 3:38 p.m. warned that storms could produce wind gusts up to 90 mph, describing the scenario as “life-threatening” with tornado-like wind speeds expected.

The line of storms moved northeast at about 60 mph, affecting communities such as Appleton, Menasha, and areas along Lake Winnebago. Forecasters warned that flying debris could be deadly, and homes, businesses, and mobile homes faced heavy damage or destruction, with widespread tree damage and power outages expected.

Animated weather footage from windy.com displayed radar images showing a line of severe thunderstorms from Illinois through Wisconsin. As the storms progressed, power outages increased rapidly. By 3:54 p.m. Central time, over 92,000 customers were without power statewide, representing about 3.1% of tracked users according to poweroutage.us.

• Alliant Energy: Nearly 44,000 customers without power
• We Energies: More than 21,000 outages
• Madison Gas & Electric: More than 10,000 outages
• Xcel Energy and Wisconsin Public Service: Several thousand outages each

County-level data highlighted significant disruptions in southern and central Wisconsin. Separate reports indicated over 3,000 customers were without power in Winnebago County during the storm’s early stages, especially in Oshkosh and nearby areas.

Illinois Power Outages

Illinois experienced even more outages, with nearly 120,000 reported by 5:13 p.m. Eastern time. The majority occurred in Will County in Northeastern Illinois. Affected utilities included:

• Commonwealth Edison Company: Over 105,000 without power
• Ameren: Over 10,000 without power
• Jo-Carroll Energy: More than 2,000 without power

Most outages affected northern and northeastern Illinois.

Looking Ahead

Though individual severe thunderstorm warnings are typically short-lived, the broader threat persists. Forecasters warned the atmospheric setup causing Wednesday’s storms may continue into the evening and Thursday, suggesting additional warnings—and possibly more severe storms—could be issued quickly.

Residents in Wisconsin and the broader Midwest are urged to stay alert for updates, as new rounds of damaging winds, hail, or isolated tornadoes could follow after initial storms pass.

As of 5 p.m. Eastern time on Wednesday, tornado and severe thunderstorm watches remained in place across the Plains and Midwest.