Travel chaos for Britons as THOUSANDS of US flights cancelled amid massive snowstorm

Beyond the mass cancellations, passengers have also contended with nearly 13,000 delays affecting arrivals and departures across American airports, according to flight tracking service FlightAware.

Flights this morning from London Heathrow to Dallas Fort Worth, Newark, Los Angeles and Washington, DC, were all cancelled.

Angela Exstrom, who was attempting to return to Nebraska from Mexico, found her Houston departure scrapped and was forced to reroute via Los Angeles.

She said: "If you live in the Midwest and travel in the winter, stuff can happen."

The ferocious weather system has placed roughly 140 million people, more than four-in-ten Americans, under winter storm warnings stretching from New Mexico to New England.

Meteorologists have warned of widespread heavy snowfall accompanied by a devastating band of ice extending from eastern Texas through to North Carolina.

National Weather Service Meteorologist Allison Santorelli said: "What really makes this storm unique is, just following this storm, it's just going to get so cold. The snow and the ice will be very, very slow to melt and won't be going away anytime soon, and that's going to hinder any recovery efforts."

Temperatures have plummeted to extreme levels, with parts of upstate New York recording -34C before dawn.

Wind chill readings in the northern Plains dropped as low as -45.5C, creating conditions where frostbite can develop within ten minutes.

Ronald Reagan National Airport in northern Virginia, situated just across the Potomac from Washington, DC, was effectively shut down entirely.

Other major metropolitan hubs fared little better, with airports serving New York, Philadelphia and Charlotte in North Carolina all experiencing cancellation rates of at least 80 per cent.

The storm deposited ice up to an inch thick across southern states, bringing down tree limbs and power lines in its wake.

At the peak of the disruption on Sunday, more than one million homes and businesses across eight states from Texas to the Carolinas lost electricity.

Tennessee suffered most severely, accounting for approximately one-third of all power cuts.

By Sunday evening, some 800,000 customers remained without electricity.

Heavy ice continued to accumulate across interior sections of the Eastern seaboard, reaching as far south as Atlanta as the storm system tracked through the Appalachian Mountains.

US President Donald Trump described the storm as "historic" and approved federal emergency disaster declarations for a dozen states on Saturday, predominantly in the mid-South region.

Meanwhile, New York Governor Kathy Hochul deployed National Guard troops to New York City, Long Island and the Hudson Valley to support emergency response operations.

Seventeen states, along with the District of Columbia, declared weather emergencies, while the Department of Energy issued orders authorising backup power generation in Texas and the mid-Atlantic to prevent widespread blackouts.

Officials have cautioned that conditions will remain treacherous for days as Arctic air continues to sweep in behind the departing storm system.

Homeland Security Secretary Kristi Noem said: "The situation with this storm is pretty unique, just because it's going to stay cold for a period of time.

"This ice that has fallen will keep those lines heavy, even if they haven't gone down immediately."