What to expect with Thursday’s winter storm

Travel conditions are expected to deteriorate fast Thursday morning, sweeping through the Chicago area between noon and 2 p.m. with as much as an inch of snow per hour this afternoon in some areas.

A powerful Arctic cold front will sweep across Northern Illinois from late morning through early afternoon from west to east, accompanied by accumulating snow, a dramatic temperature drop and gusty winds. A flash freeze may cause ice covered roads, topped by the accumulating snow, making bridges and overpasses slick.

The entire northern portion of Northern Illinois is under a winter storm warning to Saturday morning.

Blizzard conditions are expected because of snow and blowing snow Thursday night into Friday. Dangerously low wind chills as low as 30 to 40 below zero are expected, causing life-threatening conditions.

Hazardous conditions are expected to begin at 9 a.m. in the western counties: La Salle, Bureau, Putnam, Lee, Whiteside, DeKalb and Ogle. Eastern counties, such as Will, Cook, Lake, McHenry, Kane, Grundy and DuPage should start to see conditions worsen about noon.

Temperatures are expected to drop 20 to 30 degrees in a two- to three-hour span, entering the teens and single digits by 4 p.m. With wind gusts projected at 35 mph, sub-zero wind chills are expected.

Snowfall is predicted to be anywhere between 2 to 6 inches across Northern Illinois with snow rates of up to an inch per hour in some parts of Northern Illinois. That will be accompanied by heavy wind gusts, causing zero visibility at times.