Coldest wind chills in years threaten most of the US, with unusual snowfall expected in the South

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, including the Gulf Coast.

​ 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, including the Gulf Coast. Read More Breaking News, Latest News and Videos | CNN