A rare frigid storm charged through Texas and the northern Gulf Coast on Tuesday, blanketing New Orleans and Houston with snow, closing highways, grounding nearly all flights and canceling school for millions of students more used to hurricane dismissals than snow days.

Heavy snow, sleet and ice are making travel conditions treacherous across the region, stretching from Houston into the Florida panhandle.

Florida residents from Pensacola to Jacksonville are bracing for what is expected to be a historic, once-in-a-lifetime winter storm with record-breaking, single-digit temperatures and an