Hot and humid conditions across the Chicago area could help to fuel strong-to-severe thunderstorms on Wednesday, with areas in the south suburbs facing the greatest threat of nasty weather.
Things will start out on the muggy side on Wednesday, with a heat advisory going into effect for parts of central Illinois and northwest Indiana at 10 a.m.
Kankakee County is included in that advisory, as are Lake, Porter, LaPorte, Newton and Jasper counties in northwest Indiana.
According to the advisory, which runs through 7 p.m., heat indices in excess of 105 degrees are possible during the afternoon hours, with those spending any time outdoors advised to take as many breaks as possible.
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Strenuous outdoor activities should also be moved to early morning or evening hours, according to the advisory.
As the day moves along, thunderstorms are expected to develop in Canada, and will sweep into the area ahead of a cold front that is expected to descend toward the southeast during the afternoon and early evening hours.
As of 3 p.m., a large swath of central and northern Illinois and most of Indiana are considered to be at a “slight” risk of severe weather, according to the Storm Prediction Center.
That list of counties includes Lake, DeKalb, Kane, DuPage, Cook, LaSalle, Kendall, Grundy, Will and Kankakee in Illinois, as well as Lake, Porter, Newton, Jasper and LaPorte in Indiana.
The rest of Illinois and Indiana will be under a “marginal” risk of severe weather.
According to the alerts from the SPC, the biggest threat currently facing the area could be damaging and gusty winds ahead of the storms, with some hail and frequent lightning possible.
The possibility of an isolated tornado or two could not be ruled out, according to officials.
After that cold front finishes moving through the area, slightly cooler temperatures are expected, with highs rising into the low-to-mid 80s to wrap up the work week, according to forecast models.
As always, stay tuned to the NBC 5 Storm Team, and download the NBC Chicago app for Live Doppler 5 radar and more tools to keep you apprised of the weather.