More than 170 million people across the United States, from the Mexican border to the Canadian border are under cold weather alerts ahead of a crippling winter storm expected to sweep through the south from Texas to Georgia,

An arctic air mass sprawling across the eastern, central and parts of the western U.S. on Monday will channel temperatures 20-30 degrees below already historically cold January averages and is poised to slam parts of the South with a disruptive winter storm.

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