(Bismarck, ND) — Areas of North Dakota east and north of the Missouri River are under an Extreme Cold warning until Tuesday at noon. The National Weather Service says wind chills could hit as low as 55-below-zero and calls the temperatures “life-threatening.” Wind chills are expected to be anywhere between 30-and-45 degrees below zero throughout today and overnight. Even without the wind chills, temperatures will remain anywhere from ten-to-20 below zero all day today in the affected areas. Bismarck is expected to get above zero degrees by mid-morning tomorrow and other regions should start seeing positive numbers tomorrow afternoon.