6 inches of snow possible Friday

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Updated: January 19, 2012 4:35PM

Forecasters are already warning that a winter storm Friday could leave as many as 6 inches of snow in some parts of the Chicago area.

A winter weather advisory issued early Thursday for Cook, Lake, DuPage, Kane and McHenry counties will take effect Friday morning and last through Friday evening, according to the National Weather Service’s website.

Flakes will begin falling after daybreak and could accumulate to as many as 6 inches of snow before the storm tapers off by early Saturday morning, the weather service said.

The Chicago area could see up to 1 inch of new snow per hour during the heaviest part of the storm Friday afternoon during rush hour, when roads could become snow-covered and difficult to maintain, according to weather service.

Driving could become difficult or even dangerous, forecasters warn. Airport delays are also possible.

Some 1 to 2 inches of snow is possible Thursday before the larger storm moves in tomorrow, the weather service said.

However, subzero wind chills will swoop into the region Thursday night after temperatures fall this afternoon, the weather service says. Highs Thursday will be in the lower 20s with an overnight low of just 2 to 6 degrees.