Bitter Arctic air plunged more than half the US into a deep freeze Tuesday, including New Orleans, which saw the heaviest snow in decades.

A rare winter storm charging through Texas and the northern Gulf Coast on Tuesday has closed highways and airports and prompted the first blizzard warning for southeast Texas and southwest Louisiana.

Cold weather advisories and extreme cold warnings are likely next week, and officials still say snowfall probabilities could change. Here's what to know.

Heavy snow, sleet and freezing rain are expected around the Deep South as a blast of Arctic air plunges much of the Midwest and the eastern US into a deep freeze.

A snowstorm warning was in effect for 31 million people - from southern Texas east through Georgia and north to the Carolinas and into Virginia - until Wednesday morning, the National Weather Service said.