The mercury could sink tens of degrees below seasonal norms on the US Gulf Coast.
At least 10 people die, more than 1,000 flights were canceled and hundreds of thousands were without power in five states as a massive winter storm system dumped snow, freezing rain and hail from Texas to Michigan.
A winter storm that causes at least four deaths in the US South brought record low temperatures to parts of the region, where it coated roads with ice, snapped power lines and prompted public school closures.
