Warning that frostbite can take place in minutes as -40C 'bomb cyclone' is forecast to hit US

Several thousand people have lost power as the frosty weather spread this week, as Robert Moore reports

Experts are warning that people caught in a major storm sweeping the United States could suffer frostbite within minutes as temperatures in some regions are forecast to drop below -40C.

The freezing air moving across the states has also forced thousands of flights to be cancelled and led to homeless shelters overflowing as people desperately attempt to escape the chill.

In Montana, temperatures have already fallen as low as -46C at Elk Park, a mountain pass on the Continental Divide.

The frigid air was moving through the central US to the east, with windchill advisories affecting about 135 million people over the coming days, weather service meteorologist Ashton Robinson Cook said.

Places like Des Moines, Iowa, will feel like -37C, making it possible to suffer frostbite in less than five minutes.

“This is not like a snow day when you were a kid,” President Joe Biden warned in the Oval Office after a briefing from federal officials. “This is serious stuff.”

An arctic blast is bringing extreme cold, heavy snow and intense wind across much of the US this week. Credit: AP

The cold weather has brought in one of the most treacherous holiday travel seasons the US has seen in decades, with forecasters warning of an impending “bomb cyclone” that could make conditions even worse before Christmas.

More than 3,400 flights within, into or out of the US were cancelled on Friday, according to the tracking site FlightAware.

Schools and several ski areas have already closed, and several thousand people have lost power as the frosty weather spread this week.

How many people are affected?

  • 181 million people are under wind chill warnings or advisories

  • More than 11 million people are under blizzard warnings

  • 58 million people face winter storm warnings

  • More than 500,000 people are under ice storm warnings

  • More than 458,000 homes and businesses were without power on Friday morning

What is a bomb cyclone?

A bomb cyclone, or explosive cyclogenesis, is a fast-developing storm that occurs when atmospheric pressure drops at least 24 millibars over a 24-hour period.

However, a drop in pressure isn't all that is needed to classify a storm as a bomb cyclone, experts also need to analyse the latitude of the weather system.

Forecasters expected the bomb cyclone to develop late on Thursday and into Friday near the Great Lake, which will potentially stir up blizzard conditions, including heavy winds and snow.

They can typically produce winds of 75 to 95mph.

US President Joe Biden. Credit: AP

Ryan Maue, a private meteorologist in the Atlanta area, said: "For most people alive, this will be a memorable, top-10 extreme cold event.”

In South Dakota, Rosebud Sioux Tribe emergency manager Robert Oliver said tribal authorities have been working to clear roads to deliver propane and fire wood to homes, but face a relentless wind that has created drifts over 10 feet in some places.

“This weather and the amount of equipment we have - we don’t have enough,” Mr Oliver said, noting that rescues of people stranded in their homes had to be halted early on Thursday when the hydraulic fluid in heavy equipment froze amid a -40C wind-chill.

He said five have died in recent storms, including a blizzard from last week.

Travel disruption is expected over the festive period due to the poor weather. Credit: AP

In Texas, temperatures were expected to quickly plummet, but state leaders promised there wouldn't be a repeat of the February 2021 storm that overwhelmed the state's power grid and was blamed for hundreds of deaths.

The cold weather extended to El Paso and across the border into Ciudad Juarez, Mexico, where migrants have been camping outside or filling shelters as they await a decision on whether the US will lift restrictions that have prevented many from seeking asylum.

Elsewhere in the US, authorities worried about the potential for power failures and warned people to take precautions to protect older and homeless people and livestock - and, if possible, to postpone travel.

Some utilities were urging customers to turn down their thermostats to conserve energy.

Thousands of flights have been cancelled across the US. Credit: AP

“This event could be life-threatening if you are stranded," according to an online post by the National Weather Service (NWS) in Minnesota, where officials reported dozens of crashes.

The NWS has issued guides warning those venturing outdoors that in some areas frostbite could occur in minutes.

More than 2,156 flights within, into or out of the US were cancelled on Thursday afternoon, according to the tracking site FlightAware. Airlines have also cancelled 1,576 flights on Friday. Airports in Chicago and Denver were reporting the most cancelations.

Some shelters in the Detroit area already were at capacity but still making room.

“We are not sending anyone back into this cold,” Aisha Morrell-Ferguson, a spokeswoman for COTS, a family-only shelter, told the Detroit News.

And in Portland, Oregon, officials opened four emergency shelters. In the city’s downtown, Steven Venus tried to get on a light-rail train to get out of the cold after huddling on the sidewalk overnight in below-zero temperatures.

“My toes were freezing off," he said, a sleeping bag wrapped around his head, as he paused near a flimsy tent where another homeless person was taking shelter.

Courtney Dodds, a spokeswoman for the Union Gospel Mission, said teams from her organisation had been going out to try to convince people to seek shelter.

“It can be really easy for people to doze off and fall asleep and wind up losing their lives because of the cold weather."

A dog walker named Courtney walks with her dogs near Lake of the Isles in Minneapolis. Credit: AP

In famously snowy Buffalo, New York, forecasters predicted a “once-in-a-generation storm" because of heavy lake-effect snow, wind gusts as high as 65 mph, whiteouts and the potential for extensive power outages.

Mayor Byron Brown urged people to stay home, and the NHL postponed the Buffalo Sabres' home game against the Tampa Bay Lightning.

The wintry weather extended into Canada, causing delays and cancellations earlier in the week at Vancouver International Airport. 

A major winter storm was expected on Friday into Saturday in Toronto, where wind gusts as high as 60mph were predicted to cause blowing snow and limited visibility, Environment Canada said.

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