NINETEEN people have died and more than 240 million are trapped as an enormous winter storm rips through the United States.
A 'bomb cyclone' over the US Midwest - a phenomenon caused by a drastic, rapid drop in atmospheric pressure - has created an unprecedented cold-weather hurricane across much of the country.
The vast, swirling system, which extends from Texas as far north as Canada, has sparked chaos on the busiest travel weekend of the year, with hundreds of millions trying to get home for the Christmas holidays.
More than 7,000 flights have been cancelled, huge pile-ups have shut many the few roads still open and 1.5 million people are without power as temperatures plunge as low as -45C.
The US National Weather Service has told people to 'forget' about driving in the blizzards
Reuters
The US National Weather Service (NWS) said it had been forced to issue "one of the greatest extents of winter weather warnings and advisories ever" with 240 million people covered.
Some areas are expecting to 90cm of snow, with blizzard warnings in place for eight million people.
The NWS said visibility was "zero" in many areas and advised against all travel. The storm has wrecked festive plans for tens of millions, with 15,000 flights delayed, in addition to the cancellations.
A 50-vehicle pileup on the Ohio Turnpike in a blizzard near Toledo killed two drivers, injured dozens and shut down both lanes of the highway, state police reported. Stranded motorists were evacuated by bus to keep them from freezing in their cars in sub-zero temperatures, according to the Toledo Fire & Rescue Department.
Three weather-related fatalities were confirmed in neighboring Kentucky - two from car accidents and one a homeless person who died of exposure. "Please stay home and stay safe," Kentucky Governor Andy Beshear said on Twitter, announcing the deaths.
The freezing weather extended far further south than is usual, even for extreme winter storms, with temperatures falling as low as -18C in the city of El Paso, Texas, near the Mexico border. Exposure to such conditions can cause frostbite within minutes.
Hard-freeze warnings were posted in southern Georgia and across much of all four Gulf Coast states - Texas, Louisiana, Alabama and Florida. In South Dakota, Native Americans even burned clothes to stay warm after running out of fuel, said tribal officials.
Heating and energy prices spiked as inclement weather forced energy production cuts and bone-chilling cold drove demand higher.
The airport chaos was "the worst ever seen" according to officials, with 20,000 flights expected to be impacted before Christmas Day.
Transportation Secretary Pete Buttigieg said the US aviation system "is operating under enormous strain" while rail operator Amtrak cancelled dozens of trains, disrupting holiday travel for thousands.
A resident in Montana throws boiling water into the air - which instantly turns to snow
Reuters
The American Automobile Association (AAA) had estimated that 112.7 million people planned to travel 50 miles (80 km) or more from home between Friday and January 2.
That number was likely to plunge due to treacherous weather complicating air and road travel going into the weekend.
The city of Buffalo and its surrounding county on the edge of Lake Erie in western New York imposed a driving ban, and all three Buffalo-area border crossing bridges were closed to inbound traffic from Canada due to the weather.
US winter storm: Snow drifts of up to 12ft have been seen in Montana and Dakota
Reuters
Last-minute holiday gift purchases may also have slim chances of reaching their destinations by Christmas.
FedEx, United Parcel Service, the U.S. Postal Service and Amazon.com all alerted customers that severe weather was disrupting key operations in Tennessee, Indiana, Kentucky, Illinois, the Dakotas and other areas hard-hit by bitter cold and blizzards.