Weather
Illinois Weather: Rain Peaks South of I-80 Friday AM
Chicago, IL – A dry and mild Tuesday will give way to periods of rain across the Chicago forecast area through late week, with locally heavy rainfall possible Thursday.
By Paige Sullivan · 2026-09-29T13:51:38.613Z
Chicago, IL – A dry and mild Tuesday will give way to periods of rain across the Chicago forecast area through late week, with locally heavy rainfall possible Thursday.
According to the National Weather Service in Chicago, Tuesday will stay mainly dry after some early morning fog, with highs ranging from 71 to 80 degrees . Rain chances increase Tuesday night, particularly north of Interstate 80, as lows fall into the upper 50s to mid 60s .
Periods of rain are expected Wednesday, with precipitation focused mainly near and north of I 80. Wednesday highs are forecast from 68 to 81 degrees , with nighttime lows of 63 to 69 .
Thursday carries the most notable rainfall concern. The NWS said there is a threat for locally heavy rainfall during the day and at night. High temperatures could range from 68 to 83 degrees before cooler air begins moving into the region.
Rain chances continue Friday, when the NWS shows a 30% to 70% chance , with the highest chances south of I 80 during the morning. Friday highs are expected to reach only 62 to 69 degrees . A 20% to 30% chance of rain remains Friday evening, mainly south of I 80.
By Saturday, the wetter pattern should ease. Forecast highs range from 60 to 68 degrees , with nighttime lows of 45 to 53 .
Residents should expect increasingly wet conditions from Wednesday into Friday, with Thursday carrying the potential for locally heavier rainfall. Cooler temperatures then settle in toward the weekend.