Fast moving thunderstorms raced through multiple counties in the Chicago area and throughout areas of the state including Cook, DuPage, and Will counties. Winds were expected to reach over 80 mph according to the National Weather Service.
Storms are expected to proceed across the region Tuesday into the afternoon. A severe thunderstorm watch remains in effect until about 2 p.m., according to the NWS.
Severe Thunderstorm Warning continues for Chicago IL, Cicero IL and Orland Park IL until 11:15 AM CDT. This storm will contain wind gusts to 70 MPH! pic.twitter.com/QG0vUFJHQp
— NWS Chicago (@NWSChicago) August 11, 2026
18 total counties in Illinois are expected to be affected, including Cook County, with areas extending across northern and central portions of the state. Also including Livingston County in central Illinois; Ford and Iroquois counties in east-central Illinois; and Boone, DeKalb, La Salle, Lee, Ogle and Winnebago counties in north-central Illinois.
According to the NWS, the storm will also impact northwest Indiana and Wisconsin, impacting many communities near the I-74 corridor.
As of about noon, 289,633 customers, many of whom are in the south and southwest suburbs are without power due to the storms, according to ComEd.
NWS is urging residents to remain weather aware as thunderstorms develop and move through the region. Residents should expect heavy winds, with winds approaching 75 to 85 mph.
Along with the high winds, some areas potentially receiving around a quarter-inch or more of rainfall. Frequent lightning is also expected through the storm, with heavy downpours and flooding in certain areas being possible.
Residents should closely monitor weather conditions according to the NWS. As storm conditions can change throughout the morning and late afternoon. Residents are recommended to have multiple ways to receive weather alerts.
The storms were also wreaking havoc on air travel, with flights at O’Hare International Airport grounded due to thunderstorms.
According to an FAA report, arriving flights were experiencing average delays of about 2 hours and 24 minutes.
Those going to O’Hare have been recommended to check with their airlines for any flight-specific updates, as conditions change throughout the day.