Rain started Saturday morning and turned to snow, mostly for areas north of Interstate 80 in the afternoon.
A Winter Storm Warning is in effect until 1 a.m. Sunday for Cook, DuPage, Kane, Lake, and McHenry counties. The warning is in effect until 11 p.m. Saturday for Boone, DeKalb, Ogle and Winnebago counties, and until 10 p.m. for Kenosha, Racine and Walworth counties in Wisconsin.
Temperatures hovered above normal so most of the snow has melted. However, as temperatures drop overnight, roads and sidewalks are expected to be slick by Sunday morning.
WATCH: TULIPS COVERED IN SNOW
The weather forced the White Sox to postpone their game against the Detroit Tigers. The teams will make Saturday's game up as part of a split doubleheader on July 3.
If O'Hare sees more than 2.2 inches of snow from this system, it will be the greatest snowfall on record this late in the season.
A historic mid-April storm dropped as many as eight inches of snow on parts of the Chicago area less than two weeks ago. Woodstock received 8.5 inches of snow and 5.4 inches of snow fell at O'Hare on April 14.
WATCH: Snow falls as students head to prom in Huntley
WATCH: Brookfield Zoo animals enjoy April snow