Morning temperatures Thursday hit another one-day record low before a warming trend that has people along the Kankakee River watching for potential flooding.
Weather in the days ahead is changing so rapidly that some forecasts raise the possibility of thunderstorms by Monday, when highs are expected to be in the 50s.
That would mark a 70-degree turnaround from Thursday morning when a record low was set for a second consecutive day.
The temperature reached minus 21 Thursday morning at O’Hare International Airport, beating the previous record low for Jan. 31 of minus 12, according to the National Weather Service.
A low of minus 23 was recorded at 3:55 a.m. at Joliet Regional Airport, according to the National Weather Service. That, too, likely was an all-time low, but the National Weather Service does not keep historical data from Joliet.
It wasn’t quite as cold as Wednesday, another Chicago record for that date at
minus 23. The coldest recorded temperature overall for Chicago was minus 27 on Jan. 20, 1985. Temperatures warmed up to about zero degrees by afternoon and will keep increasing through the weekend.
The forecast in the coming days is a high of 21 on Friday, 38 on Saturday, 42 on Sunday and 53 on Monday. After that, temperatures are expected to fall.
In the meantime, Wilmington residents and emergency officials are watching the Kankakee River for possible flooding. The river is iced over and ice jams, if they happen, could lead to water flowing over the banks.
A section of North River Road in the Des Plaines Conservation Area already had flooded Thursday, said Dennis Housman, director of the Emergency Services and Disaster Agency in Wilmington.
“We’re just advising people that it’s time to start watching the river. Get ready to move out,” Housman said. “Most people who live on the river know what’s going on.”
Much depends on what happens as temperatures rise and ice upriver begins to break up.
“It’s going to make it interesting come Monday and Tuesday,” he said.
Some forecasts warn of thunderstorms by Monday, but that’s not in the National Weather Service forecast, said Ricky Castro, a meteorologist for the NWS in Romeoville.
Castro said rain is coming but is not expected to be heavy.
“It’s not looking like a significant threat for torrential rain or thunderstorms,” he said.