Weather
Chicago, IL Weather Update: 27° Temperature Drop by Oct. 17
CHICAGO, IL – A burst of early week warmth will give way to a noticeable fall cooldown across Chicago, with temperatures dropping 27 degrees by Saturday, Oct. 17. The shift could leave residents reach
By Marcus Hale · 2026-10-11T06:17:20.915Z
CHICAGO, IL – A burst of early week warmth will give way to a noticeable fall cooldown across Chicago, with temperatures dropping 27 degrees by Saturday, Oct. 17. The shift could leave residents reaching for jackets after several unusually warm afternoons.
According to the National Weather Service forecast for Chicago, temperatures will climb to approximately 82 degrees Monday, Oct. 12, before falling to a high near 55 degrees Saturday.
The cooler conditions could affect outdoor activities, weekend events and travel plans across Chicago and surrounding Cook County communities.
Before the temperature swing begins, Sunday, Oct. 11, brings sunny skies and a high near 72 degrees.
Sunday night remains mostly clear, with temperatures falling near 61 degrees. Southeast winds could gust to 15 mph overnight.
Monday delivers the warmest conditions of the forecast period, with mostly sunny skies and temperatures reaching 82 degrees.
South southwest winds of 10 to 15 mph could produce gusts reaching 20 mph, creating breezy conditions during holiday activities.
Tuesday, Oct. 13, remains mostly sunny, with temperatures reaching approximately 78 degrees. Commuters and students can expect favorable conditions as the regular workweek resumes.
However, the weather begins changing Tuesday night, when a 30% chance of showers develops mainly after 1 a.m.
Wednesday, Oct. 14, brings partly sunny skies and a chance of afternoon showers. Temperatures fall to approximately 67 degrees, marking an 11 degree drop from Tuesday.
Thursday remains mostly cloudy, with another shower chance and highs near 66 degrees.
Five Day Outlook: Friday brings partly sunny skies, breezy conditions and a high near 62 degrees. Overnight temperatures fall to approximately 46 degrees.
Saturday, Oct. 17, turns mostly sunny but considerably cooler, with afternoon temperatures reaching only 55 degrees.