Numbing winter cold covered the South, setting more than a dozen record low temperatures. Elsewhere, unseasonably cold air plunged morning lows below zero from the northern plains across the Mississippi and Ohio valleys and into the Northeast. Up to 16 inches of snow fell on parts of New York state. The temperature was 23 below zero at Pine Lake, Wis., and the nation's coldest reading was 33 below at Gunnison, Colo. The weather service reported record lows of 10 degrees at Huntsville, Ala.; 5 at Nashville, Tenn.; zero at Lexington, Ky.; 4 at Calico Rock, Ark.; 5 below zero at Hartford, Conn., and 13 below at Portland, Me. Rain mixed with sleet and snow covered the Florida Panhandle, the first appreciable snowfall there in 11 years. Six Carnival parades rolled briskly through New Orleans as temperatures hovered around freezing. Sleet had canceled all three Friday night processions.