At daybreak today, it was minus-2 at O'Hare International Airport and minus-4 in Aurora and Kankakee, according to the National Weather Service. Wind chills ranged from minus-10 at Northerly Island and Wheeling to minus-23 at O'Hare and minus-28 in Aurora.
Wind chills will remain around 20 below zero through the morning, according to a wind chill advisory in effect from 7 p.m. Wednesday through noon Thursday. "Frostbite and hypothermia can occur in a matter of minutes," the weather service warned.
Friday will bring the warmest temperatures expected in the next week, Birk said.
But don't get too excited.
"By warmer, we’re just calling for mid-20s for highs," with strong winds that will make it feel much colder, Birk said.
By Monday, the high may not climb above zero and wind chills could reach 30 or 40 below. On Tuesday, we may see 2 above. Maybe 10 on Wednesday.
"Really," Birk said, "there is no foreseeable end to the deep cold here."
Winter weather patterns established in December and early January tend to persist at least into February, according to the Chicago Weather Center. Computer models indicate the “clipper pattern” responsible for the harsh weather of recent days will continue — even strengthen — during the next 10 days. Expect more subzero temperatures and periods of snow.
This winter has already seen nearly three times as much snow as normal and colder that usual lows. As of Wednesday, snow totaled 45.2 inches versus the norm of 17.6 inches, and the Chicago area had 14 days with minimum temperatures of zero degrees or lower versus the norm of six days.
For updated weather forecasts, check the Tribune’s weather page.