Chicago weather: Mild temperatures give way to rain, then sharp return to winter cold

CHICAGO - Northern Illinois is in a period of weather whiplash, with mild temperatures giving way to rain this weekend before winterlike cold returns early next week.

Overnight temperatures Thursday were expected to remain mostly in the 40s, dipping into the upper 30s in parts of the Chicago area. Clouds and brisk southeast winds made conditions feel colder, with wind chills in the 30s.

Friday will bring continued cloud cover but mild conditions, with highs reaching the low 50s across much of northern Illinois. A band of rain is expected to move in after midnight and linger into early Friday morning, though most of the day should remain dry.

Cloudy skies are forecast to persist into Saturday, with highs again near 52 degrees. Rain is likely to return Sunday, with temperatures holding in the low 50s during the day before dropping sharply late.

As colder air moves in Sunday night, there is a slight chance rain could briefly mix with snow or freezing precipitation, though forecasters say no major winter weather event is expected. Roads could become slick late Sunday, especially as temperatures fall.

By Monday, daytime highs are forecast to plunge into the 20s, marking a return to winter conditions. Cold temperatures are expected to persist through midweek, with highs mainly in the 20s and low 30s.

The pattern remains unsettled, with temperatures expected to rebound again later in the 10-day outlook.