Many sidewalks, roads and expressways across the Chicago area were wet and icy.
According to Illinois State Police, there were no major weather-related trouble spots Sunday, but authorities said they were on standby for any reports of icy conditions and accidents.
Conditions overnight were more treacherous. The winter weather system moved in quickly Saturday night, causing black ice in a lot of areas. One to two inches of snow fell in McHenry County.
State police say the weather was the cause of an 11-car pileup on the Elgin-O'Hare Expressway at Gary Avenue near suburban Schaumburg. It happened at approximately 11 p.m. Saturday. Authorities say freezing rain turned into ice and caught drivers by surprise.
Two people reportedly suffered minor injuries in that crash but did not need to go to the hospital.
Icy roads and freezing rain were blamed for nearly a dozen crashes in total in the northwest suburbs.
Weather conditions Sunday morning were noticeably colder than Saturday and misty, which was giving people the faulty idea that rain was the only concern, instead of ice, as well.
Drivers were advised to watch out for black ice.
On another weather-related note, CTA Yellow Line service was suspended for a short time Sunday morning but later resumed.