A rare winter storm churned across the U.S. Gulf Coast on Tuesday, 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.

Millions of people across the northern Gulf Coast braced Tuesday for a rare winter storm that’s expected to scatter heavy snow, sleet and freezing rain around the Deep South as a blast of Arctic air plunges much of the eastern U.S. into a deep freeze.

A winter storm prompted a National Weather Service office in Louisiana to issue a first-ever blizzard warning. The storm is causing dangerous conditions from Texas to North Carolina.