A winter storm is expected to continue until daybreak Wednesday, marking the 33rd and 34th days we've seen measurable snow this winter.
"It's going to be spreading north into the area, moving into the South Side of Chicago mid-to-late this afternoon, then into the rest of the area mid-to-late this evening," said National Weather Service meteorologist Ben Deubelbeiss, whose agency has issued a winter weather advisory from 6 p.m. today until noon Wednesday.
As the snow falls, the wind will pick up with gusts of 25 mph that could whip up snow drifts during the drive home. About 2 to 5 inches of snow is expected in counties around Chicago, with less snow falling the farther north you go.
Areas to the south will be hit harder. The weather service has issued a winter storm watch for Livingston, Iroquois and Ford counties in Illinois and for Newton, Jasper and Benton counties in Indiana. Snowfalls of 5 to 8 inches are expected there.
Temperatures will drop to below zero in some places Wednesday night, starting a stretch of three nights when the low will be in the minus figures.
Based on the National Weather Service advisory, Metra, the commuter rail line, has issued a service alert warning that "weather conditions beyond our control" may impact the afternoon rush hour Tuesday and the morning rush hour Wednesday. The rail line said that speed restrictions related to low temperatures and weather conditions may result in delays.
According to the city of Chicago Aviation Authority, operations are normal at both O'Hare International Airport and at Chicago Midway International Airport, but in anticipation of tonight's storm, 345 flights were cancelled today at O'Hare and 40 at Midway.
The frequency of measurable snow this season has blown past the average of 17 days.
Only two other seasons in the past 129 years have seen more days of measurable snowfall through Feb. 3: 33 days in 1976-77 and 35 days in 1978-79.
Meanwhile, Chicago picked up an additional hour of daylight since the start of winter more than a month and a half ago. And the sunlight that shines down delivers 82 percent more energy than on Dec. 21.
Copyright © 2015, CT Now