With “near blizzard” like conditions on the way, snow is expected to fall at 2 to 3 inches an hour throughout Chicago come midnight Wednesday, the National Weather Service warns.
“I urge everyone to use caution and stay alert while we battle what will hopefully be one of the last winter storms,” Gov. Pat Quinn said in a statement on the impending storm.
The weather service has issued a winter storm warning starting at 10 p.m. Tuesday until 1 p.m. Wednesday that includes Cook, DuPage, LaSalle, Kendall, Grundy and Will counties, as well as Lake and Porter counties in northwest Indiana.
The accelerated rate of snowfall is being attributed to thundersnow, a rare and unstable type of storm system that brings thunder and lightning along with snow, according to forecasters.
Overall, about 4 to 8 inches of snow is expected to fall Wednesday until about 5 a.m., National Weather Service meteorologist David Beachler.
Rain is expected to begin Tuesday evening and will switch over to snow by late Wednesday morning, with flakes falling at a rate of 2-3 inches per hour at times, the weather service said.
State agencies are coordinating efforts in advance of the storm, according to the statement from Quinn’s office.
IDOT is readying its fleet of 1,750 snowplows to clear roads statewide, the statement said, and the Illinois Tollway is also preparing its full fleet of 182 plows.
The same warning takes effect at 1 a.m. Wednesday for Jasper and Newton counties in northwest Indiana, where snow will start falling after midnight.
Those areas could also see 4-8 inches of snow, with higher totals possible locally, the weather service said.
To the north and west of Chicago, Lake and Kane counties are under a less-severe winter weather advisory, but could still see 3-6 inches of snow by Wednesday morning.
“The further north you go, the less snow you’re going to see,” Beachler said. “The heart of it will fall in LaSalle, DeKalb and Cook County. It will then move east into Northwest Indiana.”
Illinois State Police will monitor road conditions, as will the Illinois Emergency Management Agency, which is ready to activate emergency resources if necessary.
IDOT is encouraging drivers to travel only when absolutely necessary during adverse conditions.
Air travel in and out of O’Hare and Midway will likely be “adversely impacted” Wednesday morning, according to forecasters.
After a balmy 50-plus degree Monday, Chicago won’t see springlike temperatures again until Friday, when the high is expected to reach the mid- to upper-40s, according to the weather service.