Mother Nature is making a mid-March push to turn an unseasonably warm, dry winter in Chicago into something a little more seasonable.

Between 7 a.m. Monday and 7 a.m. Tuesday, 4.9 inches of snow fell at O’Hare International Airport, according to the National Weather Service. Southwest suburban Romeoville recorded 2.9 inches of snowfall during that span of time.

Up to 10 inches of snow could pile up by midday Tuesday as a lake-effect snow system that started Monday night moves through the Chicago area, forecasters said. The lake-effect warning is in effect until 4 p.m. Tuesday in Cook, DuPage and Lake counties. In northwest Indiana, the warning is in effect until 1 a.m. Wednesday.

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The lake-effect band that started between 7 and 8 p.m. Monday in the northern suburbs had dropped 8.5 inches in Waukegan by early Tuesday, NWS meteorologist Casey Sullivan said. That band moved into northern Cook County by 4:45 a.m., and another band was expected to form somewhere in the area later in the morning.

As of 7:20 a.m. Tuesday, 422 flights had been canceled at O’Hare, and 81 were grounded at Midway International Airport, according to the city’s Department of Aviation. Delays at both airports were averaging 15 minutes or less.

Chicago’s 287 snow plows hit the streets Monday night, clearing main arteries before heading to residential blocks, according to the city’s Dept. of Streets and Sanitation. Residents can monitor the snow plow fleet in real time on the city’s website.


At midnight, this winter’s snowfall totaled 22.8 inches, the weather service said. That number is well below the seasonal average of 32.2 inches, which could be within striking distance if the lake-effect system packs its full punch.

Between 5 and 10 inches are expected, with especially “intense” snowfall overnight — up to 2 inches per hour in the most directly hit areas — making for a nightmarish morning commute, forecasters said. But because lake-effect bands are only about 10 to 15 miles wide, snow totals can greatly vary over short distances.

Slick road conditions Monday night were thought to be responsible for two separate chain-reaction crashes, involving a total of 35 vehicles, in the inbound express lanes of Interstate 90/94 between North Avenue and Division Street. Seven people were taken to the hospital with injuries that were not thought to be life-threatening, while 23 people refused medical attention.

Blowing snow made for a messy walk as commuters made their way to work on Tuesday. | Stefano Esposito/Sun-Times

In the months of January and February, not an inch of snow accumulation was recorded in Chicago — a first in recorded history. Before Monday, the last snowfall greater than an inch during this unseasonably warm winter occurred on Dec. 17 when 1.7 inches accumulated in Chicago.

While Chicago braced for its first snowfall in months, larger snowstorms were expected on the East Coast. A blizzard watch was issued for the Boston area, with 12 to 18 inches of snow expected to fall over eastern Massachusetts as well as central and southern Rhode Island, according to the weather service.