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 heightening fears of frostbite and hypothermia.
It has not been this cold for decades - 20 years in Washington DC, 18 years in Milwaukee, 15 in Missouri - even in the Midwest, where bundling up is second nature.
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 begin today and 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: minus 31 degrees Celsius in Fargo, North Dakota, minus 35 degrees in International Falls, Minnesota, and minus 15 in Indianapolis and Chicago.
At those temperatures, exposed skin can get frostbitten in minutes and hypothermia can quickly set in as wind chills may reach 45, 50 or even 56 degrees below zero.
The cold will sweep through other parts of New England where residents are digging out from a snowstorm.
Snow will reduce the sun's heating effect, so nighttime lows will plummet because of the strong north-west winds, Maue said. Fresh powder is expected in parts of the central Midwest and South starting last night night - up to 1ft in eastern Missouri and southern Michigan, 15 to 18 cms in central Illinois, eight or more inches in western Kentucky and up to 15 cms in parts of middle Tennessee.
The South will also dip into temperatures rarely seen. By tomorrow, western and central Kentucky could be at minus 18 degrees - “definitely record-breaking”, said weather service meteorologist Christine Wielgos in Paducah, Kentucky.
And in Atlanta, Tuesday’s high is expected to hover at around minus 4 degrees.
The arctic chill will affect everything from sports to schools to flights. Mike Duell, with the flight-tracking website FlightAware.com, says 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.
Before the polar plunge, Earth was as close as it gets to the sun each year yesterday. The planet orbits the sun in an oval and on average is about 93 million miles away. But every January, Earth is at perihelion, and yesterday it was only 147 million kms from the sun.
That proximity does not affect the planet’s temperatures. Mr Maue noted that it was relatively uncommon to have such frigid air blanket so much of the US, maybe once a decade or every couple of decades.
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.
Agencies