A blast of bone-chilling cold reaching lows not seen in two decades gripped the United States yesterday, sending temperatures in some areas plunging to significantly below those at the South Pole and snarling air travel.
Comertown, Montana, recorded the lowest wind chill value so far at minus 53 degrees Celsius, while North Dakota, South Dakota and Minnesota were not much warmer. That was significantly colder than the South Pole, which recorded a wind chill reading of minus 34 degrees. A wind chill reading combines actual temperature with the impact of prevailing winds.
A shift in a weather pattern known as the "polar vortex" triggered the drastic drop in temperatures. It coincided with wind chill warnings in much of the east of the country.
More than a dozen deaths were blamed on the weather.
The body of a 90-year-old woman was found face down in the snow next to her car in Ohio, the Toledo Blade reported. At least 12 other people were reportedly killed in crashes on icy roads, including four people whose sport utility vehicle slid off a rural Minnesota highway and fell into the Mississippi River.
Four Chicago men aged from 48 to 63 died of apparent heart attacks while shovelling the snow over the weekend, the Chicago Tribune reported.
Air travel was a nightmare, with many travellers trying to head home after the holidays stranded.
More than 4,300 US flights were cancelled on Monday - nearly half of those in Chicago - and more than 6,500 were delayed, according to FlightAware, a flight-monitoring site.
Airline JetBlue said it was reducing operations at four airports in the northeast: JFK, La Guardia, Newark and Boston.
Watch: Large part of US in the grip of Arctic blast
Illinois Governor Pat Quinn declared a state of emergency.
The extreme cold disrupted flights and classes in Canada as well. In the Atlantic island province of Newfoundland, over 30,000 people had no power.
The Met Office, Britain's weather forecasting body, said the high winds and heavy rain that have battered the country are loosely connected to the winter storm.
"A very strong jet stream helped to steer a lot of low pressure across the UK," said forecaster Charles Powell. Huge waves up to 8.2 metres high were recorded at Land's End, the far southwestern tip of England.