Around 40 million people in the U.S. are under a winter storm warning from an unusual blast of severe cold weather and snow across the South.

A historic winter storm swept across the Gulf Coast on Tuesday, bringing heavy snow and icy conditions to the Southeast while most of the country was facing dangerously cold temperatures from an arctic blast that arrived over the weekend.

The heavy snow, sleet and freezing rain hitting parts of the Deep South came as a blast of Arctic air plunged much of the Midwest and the eastern US into a deep freeze.