Bitterly cold air poured southward across the nation's midsection Wednesday, dropping temperatures below zero to record lows from Montana to Illinois.

The cold even extended south to the Texas Panhandle, where Lubbock shivered at 9 above zero, toppling a record for Dec. 7 that had stood since 1942, the National Weather Service said.

The body of a homeless man was found huddled next to a fence in Denver, where the temperature hit 11 below Wednesday, and authorities were trying to determine if he froze to death. He apparently had shed his jacket in a phenomenon called "paradoxical undressing," where victims of hypothermia become disoriented and hallucinate, deputy coroner Amy Martin said.

The Denver Rescue Mission opened all available space for the homeless.

A cold front has been creeping southward since the weekend.

In Gunnison, Alec Solimeo tended bar at the Timbers Sports Bar & Grill wearing a couple layers of clothing Tuesday as a faulty heater let the inside temperature drop to 42 degrees. The outside temperature fell to 12 below early Wednesday, the weather service said.

"I'm keeping these travelers happy," Solimeo said, adding that his regular customers apparently stayed home. "They're playing pool, drinking some Irish coffee and doing some singing."

A winter storm warning was issued Wednesday for counties in and around the Dallas-Fort Worth area, where the temperature fell from the low 40s before sunrise to the upper 20s by the end of the morning rush hour. Freezing rain and up to 2 inches of snow is predicted by Thursday morning.

Elsewhere Wednesday, the weather service said record lows included 28 below zero at Drummond, Mont., where the date's previous record was 21 below in 1971; 26 below at Seeley Lake, Mont.; 25 below at Laramie, Wyo., tying a 1978 reading; 17 below at Alliance, Neb.; 19 below at Cedar Rapids, Iowa; and 3 below at Lincoln, Ill.