Snow, followed by days of bitter cold coming to northern Illinois; windchills could reach 20 below

The latest weather system in northern Illinois was expected to bring more snow Friday night and throughout the day Saturday, just days after a snowstorm forced school closures and other cancellations.

Areas mainly north of Interstate 88 were getting hit Friday evening by a quick band of snow, forecast to be followed by more precipitation during the day Saturday into Sunday, according to the National Weather Service.

In McHenry County, another 1 to 3 inches of snow could fall Friday evening. Snow could fall at a rate of 1 inch per hour for an hour or two, and visibility could be reduced to a half-mile.

“Your biggest push is going to be tonight,” weather service meteorologist Kevin Donofrio said Friday. Another inch or 2 could fall Saturday, and light snow could linger into Sunday, Donofrio said.

After the weekend, the region is in for a cold snap. Windchills are expected to stay below zero for virtually the entire week, Donofrio said.

Although most schools are closed Monday for President’s Day, weather days could be possible later in the week.

Sunday and Monday nights are expected to have windchills of 15 to 25 degrees below zero, while Tuesday night’s windchills could be minus 5 to minus 20, according to the weather service.

A minus-20 windchill triggers a windchill advisory, while minus 30 triggers a windchill warning.

High temperatures are projected to be in the single digits, and overnight lows could be below zero, Donofrio said.