HELENA, Mont. (AP) — Bitterly cold air covered the state early Thursday, breaking records with temperatures falling to as low as 50 below at Elk Park north of Butte. Wind chills as cold as minus 56 were reported in Livingston.

Montana State University Billings canceled classes for Thursday over issues with heating the campus. The university is on an interruptible natural gas contract with a propane backup. Facilities services director Jason McGimpsy tells The Billings Gazette the backup system was "kicking out on us throughout the day" Wednesday. If the backup system went out, the entire campus would be without heat.

The National Weather Service says record cold temperatures were reported in Bozeman, Dillon, Fort Benton, Great Falls, Lewistown and West Yellowstone. It fell to 34 below in Great Falls, shattering the old mark of 28 below set 121 years ago in 1893.