A blizzard warning is in effect for late tonight through noon Tuesday.

According the the warning, a blizzard with whiteout conditions is expected. The warning was an upgrade from an earlier blizzard watch.

The National Weather Service said a strong winter storm system across the Dakotas will reach northern Illinois and northwest Indiana by tonight. There is a likelihood of falling and blowing snow with strong winds and extremely limited visibility.

Accumulating snow is expected to begin this afternoon, with 2 to 5 inches possible across far northern Illinois and 1 to 3 inches elsewhere, the weather service said.

Strong northwest winds gusting to 35 m.p.h. will result in significant blowing and drifting snow and possible blizzard or near-blizzard conditions overnight into Tuesday morning. Visibility may be less than a quarter-mile, and travel will become extremely dangerous and may become nearly impossible, the weather service warned.

Arctic air moving into the area behind the system is expected to produce windchills of 15 degrees below zero to 20 below late tonight into Tuesday morning.

Today's high is predicted to be about 26, but temperatures will fall to about 4 tonight with windchills as low as 8 below.

On Tuesday, temperatures will fall to around 1 below by 5 p.m., the weather service said, with windchills as low as 21 below. The low in the evening will be about 6 below with windchills as low as 17 below.

A separate winter weather advisory also has been put into effect from 3 p.m. to midnight. The advisory means that there may be travel difficulties.