Most of the United States is being assailed with extreme winter weather this week as Arctic air blasts south from Canada, snow tracks up the Northeast coast and a potentially crippling winter storm takes aim at the South.

A rare winter storm churned across the U.S. Gulf Coast on Tuesday (January 21), bringing heavy snow, ice and wind gusts to a region where flurries are unusual, while much of the United States remained in a deep freeze.

A major winter storm prompts blizzard warnings, dumping heavy snow and sleet in a region where even flurries are a rare sight.