The heaviest snow is expected from midnight through the early morning hours. Some parts of the Chicago area may see as much as eight inches of accumulation.
Rain will change over to snow late Tuesday, and a Winter Storm Warning is in effect for much of the Chicago area, including Cook, DuPage, Grundy, Kankakee, Kendall, La Salle, Livingston and Will County. Much of the rest of northern and central Illinois are under a Winter Weather Advisory. Hail was reported on the warm side of the storm in some southwest suburbs, including Lockport and Morris.
On Tuesday night in Waukegan, salt trucks were ready to go. It will be the 70th time these vehicles have been deployed this winter, nearly three times more than usual. The public works department in Waukegan has had to restock its salt supply three or four times this season, an expensive winter that continues to run up the tab.
"We're going to kind of react to it tonight, maybe start early morning when the heaviest snow is due to hit us," said Tom Hagerty, director, Waukegan Public Works.
IDOT will have all 370 of its trucks out overnight. The agency recently gained approval for an extra $47 million dollars to pay for salt and other snow-fighting expenses.
"At this moment, we are okay with our budget. We have salt. We are in contact with our vendors should we need supplemental orders," said Jae Miller, IDOT spokesperson.
Metra is warning riders of potential morning delays. The pharmaceutical company where Ana Garcia works is keeping its staff at home.
"They went right ahead and notified us this morning at 7:00, saying hey, we're having snow coming our way. Just stay home tomorrow and work from home," said Garcia.
This late blast of winter comes days before the annual dyeing of the Chicago River green this Saturday. Two years ago, temperatures were in the 80s. This year, organizers may be on the lookout for ice.
"It's not really thick, and they're able to dodge it, and the boats go right over it, and the river still turns. I mean, there's been colder days, put it that way, in the past. And they've always had the river dyed," said Kevin Sherlock, Chicago Journeymen Plumbers Local 130.
Ice is keeping some boats off the river. Sightseeing company Wendella is unable to start its season this weekend because its boats are locked in an icy Calumet River shipyard.
"We're coming. We're just not sure when. We hope no later than April 4th, maybe March 28th. But spring is coming, and we're coming with it," said Craig Wenokur, vice president, Wendella Boats.
Chicago will have a break from rain and snow, but temperatures will fluctuate through the rest of the week. The high Wednesday will drop to the mid-20s and rise to the 30s and 40s through the end of the week.