More than 160 million Americans are expected to face an unusually brutal winter storm from Friday, with heavy snows and freezing rains forecast.
The storm is expected to sweep through much of the United States, leaving extremely dangerous conditions in its wake as it tracks eastwards from the High Plains and Rockies, the National Weather Service (NWS) said.
It warned that the Arctic blast will bring sub-zero temperatures and wind chills, which pose a life-threatening risk of hypothermia and frostbite to exposed skin.
US transportation officials, including airport authorities in several major cities, have warned of weekend travel disruption, delays, and cancellations.
The winter storm is forecast to move slowly across the US, blanketing cities including Memphis, Nashville, Washington DC, Baltimore, Philadelphia, and New York with snow.
Heavy snow is predicted through the Southern Rockies and Plains, into the Mid-Atlantic and reaching the Northeast.
According to the NWS Probabilistic Precipitation Portal, regions from Colorado to West Virginia to Boston could see more than a foot of snow.
Numerous low temperature records are likely to be broken, with coldest wind chills potentially falling below -50F (-46C) across the Northern Plains.
A much wider area of the southeastern US is also forecast to experience freezing temperatures.
Governors in several states, including Arkansas, Georgia, Texas, North Carolina, and South Carolina, have declared states of emergency, allowing emergency officials to begin mobilizing response efforts.
Some airlines have offered passengers the option to change their flights without incurring extra fees due to concerns about cancellations.
Motorists are advised to avoid driving this weekend, with travel expected to be nearly impossible during the peak of the storm, according to NWS meteorologists.
In Canada, freezing temperatures are already gripping the country, with snowfall expected in eastern and Atlantic regions.
