Cities as far west as Reno, Nev., and Boulder, Colo., have also been stunned by the storm, CBS' "Good Morning" reported.
A winter storm watch was in effect in Minnesota until 6 a.m. Thursday, WCCO-TV, Minneapolis, reported. Snow had been falling across the state since Tuesday night and had reached depths greater than 2 feet in some areas, with 28 inches recorded in Two Harbors on the North Shore of Lake Superior, the Duluth News Tribune reported.
The heavy blanket of snow already on the ground had caused at least four weather-related deaths this week and closed or delayed the opening of dozens of schools across the state. Police urged drivers to stay off roads because of diminished visibility from the combination of high winds and heavy snow.
By the time the storm leaves the Northern Plains and Upper Midwest on Wednesday, between 1 and 3 feet of snow could be on ground, Accuweather.com reported. Air travel delays are likely.
People in the Western and Plains states should expect a major storm system a meteorologist at WBBM-TV, Chicago, reported.
A storm centered over the Rockies brought 6 inches of snow to Reno Tuesday and it was forecast to linger in the Plains for the rest of the week. The TV station said temperatures were to turn 20-40 degrees below normal, with record lows possible across the growing regions of California.