Light snow fell on this panhandle city Wednesday as the last remnant of an unprecedented, deadly storm rolled out to sea after smashing snow records from here to New Orleans and casting a blanket of ice across a region not targeted by such a severe wintry assault in generations.

More than 30 million Americans are under a winter storm warning in the Southern US after historic snow storms hit Louisiana and Texas late Monday night into Tuesday morning. The National Oceanic and Atmospheric Administration's Weather Prediction Center reported "life-threatening cold and wind chills".