A powerful winter storm that dumped heavy snow and glazed roads with ice across much of Texas and Oklahoma lumbered eastward into southern U.S. states Friday, prompting governors to declare states of emergency and shuttering schools across the region.

Schools as far south as El Paso, Texas, closed due to a polar vortex that has brought historically low temperatures and snowfall to parts of the U.S.

Ahead of a winter storm expected to drop several inches of snow around the Memphis area, many school districts called off class.