A major winter storm headed for Illinois Tuesday evening lasting several days could bring "extremely dangerous" and "life-threatening" travel conditions across the state, officials warned.
The storm system is expected to contain periods of heavy snow, rain, ice, high winds and bitter cold, according to the Illinois Department of Transportation, which could lead to whiteout conditions, making some roads "impassable."
“The Illinois Department of Transportation spends the entire year preparing for snow-and-ice season and is ready to respond around the clock to this significant weather event, but clearly the public needs to be prepared for the worst-case scenario and postpone all unnecessary travel,” Illinois Transportation Secretary Omer Osman said in a release. “Always remember, during extreme weather, the safest option is to stay home. If you must be on the roads, please be prepared for the real possibility of becoming stranded if you are unable to make it to your destination. Your cooperation and patience will be essential to keeping everyone safe the next several days.”
Tuesday will likely start out unseasonably warm in the Chicago area, with temperatures rising into the low-to-mid 40s across the region around the noon hour.
That’s when the weather system is expected to arrive, bringing rain showers to the area in the early afternoon.
Showers are expected to continue until the air temperature causes the precipitation to switch from rain to snow, and from there, intense snow is expected to begin falling Tuesday night and into Wednesday morning.
La Salle, Grundy, DuPage, Kendall, as well as parts of Cook and Will counties will be under a winter storm warning from 8 p.m. Tuesday through 6 p.m. Wednesday, the National Weather Service announced, as 5 to 11 inches of snow is expected to accumulate across the area.
Kane, De Kalb and northern Cook counties are also under a winter weather advisory from 8 p.m. Tuesday until 6 p.m. Wednesday.
Kankakee County, along with Lake, Porter, Newton and Jasper counties in Indiana, will be under a winter storm warning starting at 10 p.m. Tuesday, and by Wednesday afternoon, that those areas could see up to 15 inches of snow accumulation. The warning in LaPorte County will start at midnight.
The heaviest snowfall will likely occur on Wednesday morning, with a snowfall rate of up to 1 inch per hour falling during that time. That will likely cause serious travel issues throughout the region, according to forecast models, and residents are urged to postpone unnecessary travel.
Another system could follow closely behind the initial system Wednesday and into Thursday, and if it does, another 3-to-6 inches of snow could fall in the areas currently under a winter storm warning, meaning that in all residents could see up between 10 and 20 inches of accumulation in less than 48 hours.
For Chicago and surrounding suburbs, more intense snow accumulations from the storm are likely to remain to the south, but another threat could emerge Wednesday afternoon, as lake-effect snow is possible. If snow bands develop, it could combine with the arriving weather system to drive accumulations upward in the area, and could lead to additional advisories or warnings from the National Weather Service.
For those who must travel during the storm, Chicago's Office of Emergency Management and Communication and IDOT gave the following recommendations:
- Allow extra time to arrive at your destination
- Leave plenty of space between vehicles, when driving
- Ensure you have a full tank of gas prior to leaving
- Inform family and friends where you're going
- Keep an emergency kit inside your vehicle
- Give emergency vehicles and plows plenty of space
- Always wear a seat belt
- If you are involved in a crash, stay in your vehicle until help arrives
- Reminder: Using handheld phones is illegal while driving in Illinois
The snow is expected to clear out of the area by Thursday evening, and behind that storm system colder air is expected to arrive, driving temperatures down into the 20s for the remainder of the work week and into the weekend.