The United States is preparing for a severe winter storm affecting over 160 million people from Friday. The National Weather Service (NWS) described the storm as "extremely dangerous," warning of heavy snows and freezing rain from the High Plains and Rockies moving eastwards. The Arctic cold blast will bring sub-zero temperatures and wind chills that "pose a life-threatening risk of hypothermia and frostbite to exposed skin." Major cities like Memphis, Nashville, Washington DC, Baltimore, Philadelphia, and New York will face heavy snow. The storm may dump over a foot of snow from Colorado to West Virginia to Boston. Numerous low temperature records could be broken, with wind chills dropping below -50F (-46C) in the Northern Plains. Freezing temperatures will also spread across much of the southeastern US. States including Arkansas, Georgia, Texas, North Carolina, and South Carolina have declared states of emergency and mobilized National Guard troops. Travel disruptions are expected during the weekend, with airport officials warning of delays and cancellations. Some airlines offer flight changes without extra fees. NWS meteorologists Rich Otto and Tony Fracasso advised motorists to avoid driving, saying travel will be "nearly impossible during the peak of the storm." Meanwhile, Canada is already facing freezing temperatures and predicts snowfall in eastern and Atlantic regions early next week, according to meteorologist Geoff Coulson.