The death toll has soared from a severe winter storm that has put much of America into a deep freeze and turned one of the worst-hit US cities into a “war zone”.

At least 25 people died after a powerful blizzard paralysed western New York over the Christmas weekend, up from 13 killed on Sunday (local time) – and the toll is expected to rise further.

The fatalities included people who were found in snow banks, in their cars or who had died from cardiac events while ploughing or blowing snow.

Across the US, at least 55 people have died in weather-related incidents since late last week, according to an NBC News tally.

The extraordinary impact of America’s historic ‘bomb cyclone’ stretches across the nation from Canada to the Mexican border.

Temperatures have plummeted to -40 degrees, coupled with snow more than one metre deep, ice and howling winds.

The city of Buffalo, in New York State, is one of the worst-affected areas.

The New York blizzard, deemed the area’s worst in 45 years, took form late on Friday and pummelled the west of the state through the Christmas holiday weekend.

Another 30 centimetres of snow is expected to fall on parts of the state that are already buried under a blanket more than one metre deep.

New York Governor Kathy Hochul called it an “epic, once-in-a-lifetime” weather disaster that ranked as the fiercest winter storm to hit the greater Buffalo area since a crippling 1977 blizzard that killed nearly 30 people.

“We have now surpassed the scale of that storm, in its intensity, the longevity, the ferocity of its winds,” said Ms Hochul, adding that the current storm would likely to go down in history as “the blizzard of ’22”.

Ms Hochul said mother nature was hitting her region “with everything she has”.

“It is [like] going to a war zone, and the vehicles along the sides of the roads are shocking,” she said.

Ms Hochul said her city had been hit by the “blizzard of the century”.

Hundreds of national guard troops were assisting local first responders and state police on Monday as crews rescued people trapped in homes and cars, performed wellness checks and delivered food and basic needs.

Emergency workers have struggled to navigate past snow drifts to do their jobs.

Many snow ploughs, tow trucks, ambulances and other emergency vehicles dispatched over the weekend had to be rescued themselves after getting stuck in the snow, county officials said.

A driving ban was still in effect in Buffalo on Monday for safety purposes and to keep the roads clear for emergency and utility workers trying to weave through a nearly impassable obstacle course of buried cars and snow banks.

“There are cars everywhere. Everywhere. Pointing the wrong direction on roads, they’ve basically been ploughed in and they need to be dug out and towed. It’s going to take time to clear those,” Erie County Executive Mark Poloncarz said.

Streets in western New York State buried under snow. Photo: Twitter/Governor Kathy Hochul

Despite a ban on road travel, hundreds of Erie County motorists were stranded in their vehicles over the weekend, with National Guard troops called in to help with rescues hindered by white-out conditions and drifting snow.

Many snow ploughs and other equipment sent on Saturday and Sunday became stuck in the snow, “and we had to send rescue missions to rescue the rescuers”, Mr Poloncarz said.

“This is not the Christmas any of us hoped for nor expected,” he wrote on Twitter.

“My deepest condolences to the families who have lost loved ones.”

More than 123,000 US homes and businesses were without power on Tuesday morning (AEDT), with the worst-hit areas Washington, Maine and New York, according to PowerOutage.us.

Jessica Chan of Buffalo, New York, navigates knee-deep snow. Photo: AAP

Christmas Day temperatures remained well below average across the central and eastern US, and below freezing even as far south as the Gulf Coast, National Weather Service meteorologist Rich Otto said.

In Kentucky, officials confirmed three storm-related deaths since Friday, while at least four people were dead and several injured in auto-related accidents in Ohio, where a 50-vehicle pileup shut down the Ohio Turnpike during a blizzard on Friday.

Other deaths related to extreme cold or weather-induced vehicle accidents were reported in Missouri, Tennessee, Kansas and Colorado, according to news reports.