Chicago-area residents are being urged to bundle up as the coldest temperatures of the season arrive in the area late Tuesday and into Wednesday.
The National Weather Service has issued a wind chill advisory for all of northern Illinois and parts of northern Indiana.
The advisory took effect at 8 p.m. across northern Illinois and parts of northwest Indiana, including McHenry, Lake, DeKalb, Kane, DuPage, Cook, LaSalle, Kendall, Grundy, Will and Kankakee counties in Illinois.
Officials say the advisory will remain in effect until noon Wednesday across the Chicago area.
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Lake, Porter, LaPorte, Newton and Jasper counties were also be included in the advisory, but not until midnight, according to the National Weather Service. The advisory will remain in effect there until 10 a.m. Central time.
Wind chills could potentially drop to 20 degrees below zero across northern Indiana, according to the advisory.
The worst of the cold will 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, and wind chills likely won’t climb back into positive figures even when temps hit their high in the afternoon.
In areas near Rockford, wind chills could potentially plunge as much as 30 degrees below zero, with low temperatures expected to drop to 15 degrees below zero in an area that also includes DeKalb and Dixon, among other communities.
Wind chills in most of the northern and western suburbs will likely fall between 20 and 25 degrees below zero, while the southern suburbs and the city of Chicago will see wind chills of 15-to-20 degrees below zero.
In those kinds of conditions, frostbite can occur in less than 30 minutes on exposed skin, according to NWS officials.
Relief will be hard to come by Wednesday, with highs likely remaining in the single digits and into the teens in some locations, but overnight lows Wednesday and into Thursday will be slightly warmer, according to forecast models.
Thursday will see a chance of snow and warmer conditions, with temps in the upper-20s and into the mid-30s, but those temperatures could be accompanied by a chance of snow showers, 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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