Officials warned residents across the South that the effects of a major winter storm were not over, and that driving remained a hazard on roads frozen with slippery ice.

More than 220 million people across the United States are facing dangerous cold that will also open the door for a potentially historic and crippling winter storm that could deliver snow as far south as Florida and the Gulf of Mexico.

A winter storm sweeping through the U.S. South on Tuesday was dumping snow at levels millions of residents haven't seen before.