A polar vortex is slated to sweep most of the continental US bringing winter storm warnings and a hazardous freeze to millions.

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

Frigid temperatures engulfed the South on Monday ahead of a winter storm that's expected to spread heavy snow and disruptive ice around a region from Texas to north Florida that rarely sees such weather,