Winter Storm Warning for Chicago-area Sunday: Deteriorating travel conditions, heavy snowfall expected

Winter Storm Warning

CHICAGO — The National Weather Service has issued a Winter Storm Warning for a large portion of the Chicago area Sunday (pink-shaded counties on the map.)

The warning, which goes into effect at 10 a.m. Sunday, will impact the following Illinois counties:  Winnebago, Boone, McHenry, Lake Lee, Ogle, DeKalb, Kane, DuPage, Cook, LaSalle, Kendall, Grundy and Will.

The warning calling for 4 inches to as much as a foot of heavy wet snow.

Winter Weather Advisories for 2 to 4 inches of snow are in effect for southernmost Kankakee, Ford, Iroquois and Livingston Counties in Illinois. Strengthening north to northeast winds gusting at times over 35 miles per hour will cause blowing and drifting snow, low visibility and possible downed trees/power lines.

Travel conditions will deteriorate from west to east across the Chicago area, beginning early Sunday morning with rain quickly transitioning to an accumulating heavy wet slushy snow that will cover the entire area into northwest Indiana by late in the day. Snowfall rates in excess of 1 inch per hour will be possible.

Conditions will likely deteriorate further at night, as snow builds up with blowing and drifting and lowering visibility, combining with temperatures falling into the lower and middle 20s creating icy conditions. Total snow accumulations could be from 4 to 12 inches with the highest amounts north and west and the lowest amounts south and in downtown Chicago. Lesser snowfall amounts are expected in northwest Indiana. Snow should gradually diminish/end from the west later Sunday night and Monday morning.

The National Weather Service says holiday returning travel could be very difficult Sunday, so an earlier start/arrival would be very beneficial.

For the latest weather updates, go to wgntv.com/weather.