A storm that might be the worst of the winter swept into the Dakotas on Tuesday, prompting some schools to close and sending people to stores for provisions. Most of North Dakota, South Dakota, Minnesota, and Wisconsin were under some type of blizzard or winter weather warning or advisory through Wednesday, the National Weather Service said. The heaviest snow was expected in southeast North Dakota and northeast South Dakota, a region that could see freezing rain and a foot of snow or more with strong winds. Crews are ready with road salt as freezing rain is also expected from southeast South Dakota and southern Minnesota and east into southern Michigan.