After a mild few days, temperatures will rise into the 90s Thursday afternoon ahead of overnight thunderstorms that could be severe, forecasters say.
The temperature will top out at 91 degrees at O’Hare International Airport before the storms hit shortly after midnight, according to the National Weather Service.
The storms could be “severe with damaging winds up to 65 mph and hail up to the size of ping pong balls possible,” the weather service said in an advisory.

National Weather Service
Heavy rain and flooding is also possible, the weather service warned. Between a half and three quarters of an inch of rain is possible.
Temperatures will continue to hit the 90s or upper 80s throughout the weekend, but Friday could feel the hottest with a heat index in the mid-90s.
“With the humidity, it’s not going to be pleasant,” weather service meteorologist Brian Leatherwood said.
Another thunderstorm could move through the area Friday afternoon, but it may be localized south of Interstate 80.

National Weather Service