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

A dangerous winter storm sweeping across the South has prompted Blizzard Warnings for portions of Texas and Louisiana, new wildfires have erupted in Southern California, and the polar vortex continues to tighten its grip across the U.

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