It was a brutal morning for the Chicago area Wednesday, with some wind chills dropping as low as -41 degrees as a deep freeze closed a number of schools with an advisory in effect for several more hours.
But how long will it last?
The worst of the cold is expected to occur in far northern Illinois, according to National Weather Service forecasts. The coldest wind chills will likely be recorded between 3 a.m. and 9 a.m. Wednesday.
Parts of the Chicago area woke up to brutal values, with places like Aurora recording a feels-like temperature of -41 degrees around 5 a.m. In DeKalb, wind chill values of -30 were reported. In Winnetka, wind chill values around -29 were also recorded.
The National Weather Service reported the Aurora Airport, which is located in Sugar Grove, "is a perennial cold spot."
"Most recent observation there reported a 10 mph wind. At -20 that'll produce a cold wind chill," the NWS tweeted Wednesday.
In those kinds of conditions, frostbite can occur in less than 30 minutes on exposed skin, according to NWS officials.
The air marks the coldest of the season so far and it appears there will be little relief throughout the day as the feels-like temperatures look to stay below zero for nearly the entire day.
Some locations may climb just above zero degrees briefly during the afternoon, but as the sun sets, those numbers will fall once again.
The National Weather Service has issued a wind chill advisory for all of northern Illinois and parts of northern Indiana.
Officials say the advisory will remain in effect until noon Wednesday across the Chicago area. For Lake, Porter, LaPorte, Newton and Jasper counties, however, the advisory will remain in effect until 10 a.m. CT.
The good news is some relief is on the way.
Overnight lows Wednesday and into Thursday will be slightly warmer, according to forecast models.
Thursday will see a chance of snow showers or flurries paired with warmer conditions, with temps in the upper-20s and into the mid-30s, according to forecast models.
Temperatures will dip again Friday into the teens and 20s, but by Sunday things could warm back up to the freezing mark, officials said.
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