It is than Antarctica in parts of the USA. This is of a polar vortex - freezing air and from the Arctic. This happens. There is a state of in many towns. Schools and have closed. People were told to travel. They were told not to go or breathe the air.
The in a part of Minnesota fell to -60º Celsius. The Chicago River and Niagara Falls turned to . The cold killed people. Officials told to go outside only if . Freezing air can be for the . It can cause problems. Shoveling can also be .