A deep freeze expected in the US Midwest, north-eastern New England states and even the South will be one to remember, with potential record-low temperatures.
It has not been this cold for decades.
Weather Bell meteorologist Ryan Maue said: “If you’re under 40 you’ve not seen this stuff before.”
Preceded by snow in much of the Midwest, the frigid air will extend into early next week, funnelled as far south as the Gulf Coast.
It is being blamed on a “polar vortex” as one meteorologist calls it, a counterclockwise-rotating pool of cold, dense air.
“It’s just a large area of very cold air that comes down, forms over the North Pole or polar regions … usually stays in Canada, but this time it’s going to come all the way into the eastern United States,” said National Weather Service meteorologist Phillip Schumacher in Sioux Falls, South Dakota.
The forecasts are startling: -31C in Fargo, North Dakota, -35C in International Falls, Minnesota, and -26C in Indianapolis and Chicago.
At those temperatures, exposed skin can get frostbitten in minutes and hypothermia can quickly set in.
The Arctic chill will affect everything from sports to schools to flights. A flight-tracking website said to expect airport delays and flight cancellations because of the cold temperatures.
Minnesota has called off school tomorrow for the entire state – the first such shutdown in 17 years.
At least 16 deaths were blamed on a snow storm that swept across the eastern half of the US, including three people who officials said died at least partly because of the extreme cold.
The cold temperatures kept the snow light and powdery, preventing it from weighing down electrical lines or tree limbs. As a result there were only a few thousand power cuts in the North-east.