A quiet, dry day is in store for the Chicago area Thursday, but things will start to change overnight as lake effect snow begins to build in western Michigan, leading to a “prolonged” period of snow for northeast Illinois and northwest Indiana Friday and Saturday.

Cook County is now under a Winter Storm Warning as bursts of lake effect snow will hit the city, south suburbs and Northwest Indiana Friday and Saturday.

A significant lake effect snow event is setting up the Chicago area this weekend. A Winter Storm Watch has been issued for south and central Cook County and Lake and Porter counties in Indiana for Friday afternoon/evening.

Several rounds of lake-effect snow could potentially make for dangerous travel conditions in northwest Indiana, prompting a winter storm watch.

Wind chills of 20 degrees below zero are forecast for Sunday night. O'Hare Airport records 4.4 inches of snow. Temps will rise to the upper teens early in the week, and no precipitation is in the forecast.

At least on paper, Chicago is experiencing a warm-up to finish this weekend and begin February.

The Chicago area will be under an Extreme Cold Warning on Friday. Local officials are warning residents to be ready for the brutal cold.

SATURDAY: Mostly cloudy and continued quite frigid with highs nearly 25 degrees below normal. AM wind chills: -15 to -30 degrees. Slight chance of a snow shower early and again later in the day, but only about 20% of the metro area is likely to see any snow.

Here are the latest updates on Chicago's cold weather forecast for Sunday's divisional playoff game between the Bears and Rams.