National Weather Service United States Department of Commerce

A wave of light snow has moved into eastern Iowa and northwest Illinois late tonight, which will lead to minor accumulations and slick travel on area roads. The snow has yet to reach the ground south of the I-80 corridor, but may for a brief time over the next few hours.
Light snow is possible late tonight and into Monday morning, with the highest amounts forecast across northern IL. This snow will end from west to east prior to morning commute for most.
It will be dangerously cold Monday night through Thursday morning. Wind chills will be between -10 and -30 degrees Tuesday, Wednesday, and Thursday mornings. Wednesday morning is expected to be the coldest with wind chills up to -35 along the Highway 20 corridor. If you must go out, be sure to bundle up and cover exposed skin.