Chicago, Illinois – A punishing stretch of extreme heat and humidity will blanket much of Illinois through Thursday night, sending heat indices soaring above 105°F and prompting urgent warnings for heat-related illness and storm threats.
According to the National Weather Service in Chicago, the most dangerous period begins Wednesday and continues into Thursday night. Peak heat indices above 105°F and overnight lows feeling like 75°F will leave little room for relief, particularly in urban areas like Chicago’s heat island zones.
Widespread impacts are expected statewide, including Springfield, Rockford, Peoria, and the Metro East. Residents are urged to hydrate, avoid strenuous outdoor activity during peak afternoon hours, and never leave children or pets in vehicles. Air-conditioned spaces are essential for those without access to cooling at home.
Storm chances increase Thursday night into Friday, bringing the potential for heavy rainfall and localized flooding. Some storms may be severe. A cold front moving in Friday could suppress the extreme heat, though humidity will linger into Saturday.
Additional advisories may be issued, especially as storm timing becomes clearer. Stay alert and check in on vulnerable neighbors.
☀️ Five-Day Forecast for Illinois:
- Tuesday: Highs 83–90°F. More humid. Chance of late-day storms.
- Wednesday: Highs 91–96°F. Heat index >105°F. Hot and humid.
- Thursday: Highs 92–97°F. Dangerous heat continues. Storms possible late.
- Friday: Highs 79–86°F. Periods of storms. Humid but slightly cooler.
- Saturday: Highs 82–89°F. 30–50% chance of lingering storms. Humid.
