States including Minnesota, Wisconsin and South Dakota are forecast to get Siberian-like temperatures.
Wind chills will help some cities reach their lowest temperatures in decades.
Waterloo in Iowa is one of the places that could set an all-time low, and -36.6C (-34F) is forecast on Wednesday.
Chicago is already blanketed in snow but is set to hit -29C (-20F) the same day. The last time it reached that temperature was 1994.
But with high winds in the Windy City, it could feel like -42.8C (-45F).
When it gets this cold, I never get tired of taking a pot of hot boiling water, going outside, and tossing it up into the air and watching the water instantly turn into little micro-flakes. It's fun. Be careful if you try this.