Dangerous below-freezing temperatures with even colder wind chills were also expected to last over much of the week in the region. Authorities say three people have died in the cold weather.

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

A rare frigid storm is charging through Texas and the northern Gulf Coast, blanketing New Orleans and Houston with snow, closing highways and grounding nearly all flights.