Editor’s note: The severe thunderstorm warnings and watches have since been lifted. Find the latest weather updates here.
Severe thunderstorm warnings were in effect for some Chicago-area counties Friday as much of the region was placed under a severe thunderstorm watch that lasts for hours.
Severe thunderstorms capable of producing “all types of severe weather,” including “large hail and tornadoes” was spotted near Genoa and was moving southeast at 20 mph, according to the National Weather Service.
Just before 5 p.m., another storm near Rochelle was making its way to DeKalb County, with officials urging residents to “remain alert for a possible tornado.”
The system sparked severe thunderstorm warnings in at least three counties.
Here are the most recent alerts:
Severe Thunderstorm Warning
South central LaSalle County until 9:45 p.m.
Severe Thunderstorm Watch
Illinois
DeKalb
LaSalle
Cook
DuPage
Grundy
Kane
Kankakee
Kendall
Will
Indiana
Lake
Newton
Thunderstorms were expected to fire up Friday afternoon and evening across the Chicago area.
About 11 a.m., Live Doppler 5 radar showed some showers already developing across multiple Chicago suburbs. Over the border in Wisconsin, heavy rain and storms were passing over Milwaukee.
In Illinois, an isolated thunderstorm was possible between 2 and 3 p.m., NBC 5 Storm Team Meteorologist Pete Sack said, though the main event was expected to come later in the evening.
“It looks as though the severe weather window will open up at 3 p.m. at the very earliest, until midnight at the very latest,” Sack said. “Main area of storms looks to arrive between 7 and 10 p.m.”
The Storm Prediction Center has placed the entire Chicago area under a “slight” risk of severe weather, which ranks as level two of five. Damaging winds, large hail, heavy downpours and even an isolated tornado were all possible, Sack said, which could hit right as outdoor events take place.
“If you hear thunder, you can be struck by lightning,” Sack said. “So especially at those football games, head to your car waited out in the car. That’s the best place as we see these storms roll their way on through.”
The greatest tornado and severe weather threat lies west of the Fox Valley and north of I-80, the National Weather Service said.
(🧵1/2) Scattered thunderstorms are expected this afternoon and evening. A few storms may become severe with damaging winds and large hail the main threats. Be sure to have multiple ways to receive warnings! #ILwx #INwx pic.twitter.com/icLIIpdKtd— NWS Chicago (@NWSChicago) August 21, 2026
Editor's note: The severe thunderstorm warnings and watches have since been lifted. Find the latest weather updates here.
Severe thunderstorm warnings were in effect for some Chicago-area counties Friday as much of the region was placed under a severe thunderstorm watch that lasts for hours.
Severe thunderstorms capable of producing "all types of severe weather," including "large hail and tornadoes" was spotted near Genoa and was moving southeast at 20 mph, according to the National Weather Service.
Just before 5 p.m., another storm near Rochelle was making its way to DeKalb County, with officials urging residents to "remain alert for a possible tornado."
The system sparked severe thunderstorm warnings in at least three counties.
Here are the most recent alerts:
Severe Thunderstorm Warning
South central LaSalle County until 9:45 p.m.
Severe Thunderstorm Watch
Illinois
Indiana
Thunderstorms were expected to fire up Friday afternoon and evening across the Chicago area.
About 11 a.m., Live Doppler 5 radar showed some showers already developing across multiple Chicago suburbs. Over the border in Wisconsin, heavy rain and storms were passing over Milwaukee.
In Illinois, an isolated thunderstorm was possible between 2 and 3 p.m., NBC 5 Storm Team Meteorologist Pete Sack said, though the main event was expected to come later in the evening.
"It looks as though the severe weather window will open up at 3 p.m. at the very earliest, until midnight at the very latest," Sack said. "Main area of storms looks to arrive between 7 and 10 p.m."

The Storm Prediction Center has placed the entire Chicago area under a "slight" risk of severe weather, which ranks as level two of five. Damaging winds, large hail, heavy downpours and even an isolated tornado were all possible, Sack said, which could hit right as outdoor events take place.
"If you hear thunder, you can be struck by lightning," Sack said. "So especially at those football games, head to your car waited out in the car. That's the best place as we see these storms roll their way on through."
The greatest tornado and severe weather threat lies west of the Fox Valley and north of I-80, the National Weather Service said.
(🧵1/2) Scattered thunderstorms are expected this afternoon and evening. A few storms may become severe with damaging winds and large hail the main threats. Be sure to have multiple ways to receive warnings! #ILwx #INwx pic.twitter.com/icLIIpdKtd
— NWS Chicago (@NWSChicago) August 21, 2026