A rare frigid storm charged through Texas and the northern Gulf Coast on Tuesday, blanketing New Orleans and Houston with snow that closed highways, grounded nearly all flights and canceled school for more than a million students more used to hurricane dismissals than snow days.

For example, Lake Charles, La., along the Gulf Coast, showed snowfall rates of over 1 inch per hour this morning and early afternoon and visibility down to a quarter of a mile with blowing snow. This is one of the reasons why blizzard warnings were posted briefly for that region earlier.