Monday is set to be the coldest day of the arctic air outbreak, where temperatures will be subzero across Montana, the Dakotas, Wyoming, Minnesota and Wisconsin.

Arctic air is creating chilly conditions for millions of Americans out shopping on Black Friday, as another shot of even colder air from a disrupted polar vortex is expected to further plunge ...

In the Arctic, winter can last for months without a single ray of sunlight, yet life there never completely stops. Beneath ...