The Minnesota Department of Transportation pulled snowploughs off the roads in nearly a dozen southeastern counties of the US state because of the extreme cold.
Meanwhile, another state, Wisconsin, added state offices and agencies to its long list of closures.
Minnesota transport officials said some snowploughs were experiencing mechanical problems because of subzero temperatures, so officials decided to idle all of them overnight.
Officials said they did not want to put drivers in danger if the ploughs malfunctioned.
Operations resumed early on Wednesday, after overnight temperatures in the area dropped to -29F (-34C).
In Wisconsin, Governor Tony Evers issued an executive order closing all non-essential state offices, when the wind chill was forecast to be as cold as -55F (-48C).