The storm is now forecast to drop between five and eight inches of snow across the area, according to the weather service.
Milwaukee also reached its No. 2 coldest holiday week with an average temperature of 6.1 degrees.
In Iowa, Massachusetts, Indiana, Ohio and North Carolina, school districts cancelled or delayed the start of classes as bitterly cold weather, 20 degrees to 30 degrees F (11 to 17 degrees C) below normal, were expected across the eastern half of the United States.
Officials with the Madison County Sheriff's Office said early Sunday that while most highways in the county are clear, roads south of Huntsville may be slick.
The chilly temperatures also hit NY as the The National Weather Service said wind chills could make temperatures feel below zero. South Central Wisconsin is under a wind chill advisory until noon on Tuesday, as it could feel as low as 25 degrees below zero outside.
The arctic air will finally shift to the east, returning high temperatures to seasonal levels. Coastal areas in Georgia and SC will start to experience smaller amounts of snow, from as early as late Tuesday.
Despite sub-freezing temperatures and warnings from the National Weather Service, the icy weather did not deter hundreds of people from ringing in the new year by jumping into Lake Michigan as part of the "Polar Plunge".
Authorities opened warming shelters in the South as temperatures dipped notably close to zero in Alabama and Georgia. The average temperature was 48.3 degrees, according to the weather service.