National Weather Service United States Department of Commerce

Warmer and mostly dry conditions are expected tomorrow, with the exception of a few decaying showers and storms which could move into parts of northwest and far northern IL. Sunday will be even warmer, with increasing humidity leading to afternoon heat index values in the 95-99 degree range. Scattered showers and thunderstorms will likely become more numerous Sunday night into Monday, as a cold front approaches and then moves through the area. Thunderstorm chances then shift mainly south of the I-80 corridor into mid-week, with somewhat cooler air behind the front.