US winter storm threatens to bring Christmas travel chaos

Chicago in path of powerful storm that could become 'bomb cyclone'

Clearing a drive after a snowstorm in Duluth, Minnesota. Parts of the US face severe weather over Christmas. AP

Chicago is in the crosshairs of a powerful winter storm that could become a “bomb cyclone” — with deep snow, searing winds and an Arctic chill — threatening to disrupt Christmas travel for millions of people in the US.

While the city, a major US air hub, may only get 13cm of snow, it will be hit with winds that could make temperatures feel like minus 37°C (minus 35°F), according to the National Weather Service.

United Airlines, Delta Air Lines, American Airlines and others have issued travel waivers so passengers can rebook holiday travel with no fees. An estimated 112.7 million people are expected to travel 80km or more from December 23 to January 2, according to motorists' group AAA.

“Over two-thirds of the country has something related to this system,” said David Roth, a senior branch forecaster at the US Weather Prediction Centre.

“About the only places not affected are parts of the Great Basin, the Southwest, Hawaii and Puerto Rico.”

Chasing the storm — which will also hit eastern Canada and trigger storms across the Great Lakes — is a cold front that will send temperatures plunging for the eastern two-thirds of the US. That will drive a frigid wedge as far south as Texas and central Florida, boosting energy demand as people turn up their thermostats to beat the chill.

The Texas energy grid is being closely watched because another sharp cold event brought it to its knees in February 2021. This current event isn’t expected to last as long. The low in Dallas is forecast to hit minus 12°C, with the wind-chill making it feel closer to minus 21°C in places.

The snow will probably miss New York and the other big cities in the North-east, but rain and high winds could buffet the region before temperatures plummet.

After the storm sweeps across the US, it is forecast to bring snow and rain across eastern Canada. The heaviest snow will likely miss Toronto, but the city could find itself in the midst of a flash freeze when temperatures drop, according to Environment and Climate Change Canada.

On both sides of the border, the cold air and relatively warm water in the Great Lakes will lead to heavy snowfall on the eastern shorelines.

Temperatures will start to rebound on Christmas Day, except in the South where the cold could linger for a few days, Mr Roth said.