A potent winter storm that buried much of the US Plains and left at least three people dead moved into Chicago on Tuesday, forcing hundreds of flight cancellations.
The National Weather Service's Chicago office issued a winter weather advisory from noon until 9 pm Central time.
Forecasters predicted the storm, which packs a dangerous mix of wet snow, sleet, rain and high winds, would reach peak intensity around the evening rush hour, reducing visibility and creating treacherous driving conditions.
The Illinois Tollway agency, which maintains nearly 300 miles of highway around Chicago, said it was mobilising its fleet of more than 180 snowploughs in anticipation of the storm, which was expected to dump six inches of wet snow north of the city.
At Chicago's O'Hare Airport, sleet and low clouds on the front end of the storm were causing delays of nearly two-and-a-half hours, according to Flightaware, and nearly 300 arrivals and departures were cancelled at O'Hare and Midway airports.
In Oklahoma, Texas and parts of Kansas, where some residents were still digging out from a winter storm last week, the storm dumped up to 17 inches (43 cm) of snow on Amarillo, Texas, and whipped Kansas City, Missouri, with winds of up to 30 miles (48 km) per hour.
Highways in the Texas and Oklahoma panhandles and parts of Kansas remained closed because of heavy and drifting snow.
Forecasters with the National Weather Service said the storm would dump 3 to 5 inches of wet snow on Detroit overnight and into Wednesday morning.
Kansas City was also hard hit by the storm, which dumped 13 inches of snow on some parts of the metro region on Tuesday, said Chris Bowman, meteorologist for the National Weather Service.