It's a "once-in-a-generation" storm, warns the Weather Service in Buffalo, New York.
A powerful winter storm is expected to batter much of the United States this weekend, threatening to create chaos.
Just as tens of millions of Americans plan to travel for the holiday season.
The storm is expected to begin building overnight Wednesday, strengthen through Friday and persist through the Christmas weekend, bringing with it extremely low temperatures, snowfall and strong winds to much of the north and east of the country, according to the US Weather Service.
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The Midwest and the Great Lakes region will be particularly affected this weekend, with blizzards.
The mercury is expected to drop very sharply in just a few hours, reaching a felt temperature of up to -55°C in the Great Plains region.
"A cold of this magnitude could cause frostbite on exposed skin within minutes, as well as hypothermia and death if exposure is prolonged," the NWS warned.
The gusts can also blow up to 80 km / h, causing possible falling trees and power cuts.
"Cyclone Bomb"
The private meteorological site AccuWeather warns of the possible formation of a "cyclonic bomb", formed by the meeting of polar air with a mass of warmer air, causing a very rapid drop in pressure.
These conditions will be "very dangerous" for travel, whether by road or air, warns the NWS.
Already on Wednesday, strong winds or snowfall threatened to create delays at Minneapolis airports, and to slow air traffic in Denver and Chicago, warned the American aviation authority.
From Thursday, millions of Americans are expected at the country's airports: the holiday season this year will undoubtedly be "busier" than in 2021, with a return "to the level before the pandemic", according to the Transportation Safety Agency.
112 million people plan to travel
United Airlines has “encouraged” its customers to check the status of their flight, and even to change it “free of charge”.
Roads also promise to be busy, with 102 million Americans having to drive to where they will be spending the holidays, according to the American Automobile Association.
In total, about 112 million people must travel at least 80 km between December 23 and January 2, according to this organization.
Cold watches and alerts have been issued in portions of at least 26 states, according to the NWS, and stretch from the border with Canada to the Gulf Coast of Texas.
The snow is not the most disturbing manifestation, but rather the cold and the winds.
The heaviest snowfall is expected in the Great Lakes region between Wednesday evening and Friday, with just over 30cm expected.
In February 2021, freezing cold hit Texas, causing a spike in energy consumption followed by massive power outages lasting several days.
The meteorological services wanted to be reassuring this time in this state, the temperatures should be lower there and for less time than during this episode.