There are multiple concerns on Wednesday afternoon through Thursday morning. Southerly winds will draw mild, well above freezing temperatures back northward on Wednesday. Then a cold front will sag south toward the area by dark, with areas of fog possibly developing near and just behind the front.
Most notably, light precipitation will develop during the late afternoon and continue through the evening as colder air sinks south. Light rain will likely transition to freezing rain and/or freezing drizzle in northern Illinois during the evening. It’s possible that freezing rain threat could affect the Wednesday evening commute in far northern Illinois, with areas along/north of I-88 and outside of Chicago most susceptible.
The freezing rain/drizzle threat will then continue to gradually sink south Wednesday night as temperatures fall. Finally, a period of light snow could occur before the precipitation ends in parts of northern Illinois and far northwest Indiana on Thursday morning. Please continue to stay tuned for the latest forecast updates and prepare for the possibility of hazardous travel during the Wednesday evening and Thursday morning commutes.