Chicago could see its longest stretch of sub-zero temperatures in over 30 years as the latest deep freeze grips the Midwest.
Frigid temperatures moved into the region overnight on Sunday and are expected to hold into Tuesday.
If Chicago makes it to 60 straight hours below zero, it would be the longest stretch since 1983 - when it was below zero for 98 hours - and the third longest in 80 years.
Forecasters told residents in the Windy City on Monday to brace themselves for temperatures dipping to -40C with the wind chill.
The latest cold snap forced Chicago Public School officials to cancel classes for nearly 400,000 students on Monday and Tuesday.
Some suburban districts and schools in Michigan and elsewhere followed suit.
In South Dakota, officials warned of treacherous driving conditions as the latest round of plunging temperatures had many people wondering when it would end.
"I'm moving to Alaska where it's warmer," Kathy Berg said in jest - though it is in fact true of current weather conditions.
In Indiana, where 50mph gusts were recorded early on Monday, officials recommended only essential travel in many areas of the state.
Michigan expressways closed as snow and sub-freezing temperatures played a role in multiple crashes on Sunday.
At least three people died over the weekend because of weather-related accidents.
In New Jersey, a man told police two men beat him unconscious and took his wallet after his car got stuck in the snow.
Temperatures are expected to be well below zero but with wind chills the temperature will be pushed even lower as the cold front moves east.
Forecasters expect -43F (-41C) in Minneapolis, -23F (-30C) in Chicago, -18F (-27C) in Dayton, Ohio, -14F (-25C) in Kansas City, Missouri.
Freezing cold is also being predicted for Sunday's Super Bowl, which will be held at MetLife Stadium in East Rutherford, New Jersey.
It has been one of the coldest winters in memory across large sections of the US after a polar vortex sent temperatures plunging to record lows several weeks ago.
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