Chicago, Illinois – Dangerous heat and stormy conditions will grip much of northern Illinois through the weekend, creating challenging and at times hazardous conditions for travel and outdoor activity. Peak heat indices could climb as high as 110 degrees Saturday afternoon, especially south of Interstate 80, before rounds of strong storms push through.
According to the National Weather Service in Chicago, a cluster of storms is expected to form in Wisconsin by mid-afternoon Saturday before racing south into Illinois. Damaging winds and torrential rainfall are the primary threats, with additional storms likely after dark that could trigger localized flash flooding.
Saturday’s heat will drive highs into the low 90s with oppressive humidity. Chicago, Joliet, and Kankakee may see brief relief during storm activity, but dangerous conditions remain possible into the evening. By Sunday, highs ease slightly into the 80s, though scattered storms remain possible.
Residents are urged to limit outdoor activity during peak heating hours, stay hydrated, and avoid non-essential travel if storms approach. Charge devices and monitor local alerts in case of power outages.
Cooler and less humid weather is expected to arrive by Wednesday, offering a break from the extreme pattern.
Five Day Forecast for Chicago, Illinois
- Saturday: High 88–93, heat indices up to 110, 40% storm chance, lows near 70.
- Sunday: High 77–88, isolated storms, low near 70.
- Monday: High 89–94, storms possible, lows near 72.
- Tuesday: High 84–92, scattered storms, low near 66.
- Wednesday: High 75–81, turning cooler and less humid, low near 62.
