US weather: 10,000 flights cancelled and more than 850,000 without power as huge winter storm hits

More than 850,000 households are without power and 10,000 flights have been cancelled as a huge storm hits US states from the southern Rocky Mountains to New England.

At least 180 million people in 37 states - more than half America's population - are affected, according to the National Weather Service (NWS).

Seventeen states and the District of Columbia have declared an emergency, with rescue teams and supplies on standby.

Parts of the northeast could get as much as 2ft (60cm) of snow overnight into Monday, said the NWS.

The forecaster also warned of freezing rain and "catastrophic ice accumulation" in areas that avoid the snow and "dangerously cold wind chills" for tens of millions.

Josh Weiss, from the National Oceanic and Atmospheric Administration, said the storm was "unique" due to its broad spread, covering 2,000 miles, and the extreme cold it's forecast to leave behind over the next week.

More than 10,000 flights have been cancelled on Sunday and another 8,000 delayed, according to tracking website FlightAware.

The cancellations are the most on any day since the COVID pandemic, said aviation analytics firm Cirium.

Homeland security secretary Kristi Noem urged people to "stay home" due to "very, very cold" temperatures.

Thousands of refuse lorries have been fitted with snow ploughs in New York City, said mayor Zohran Mamdani, who warned of the coldest temperatures for eight years.

Some people in Central Park used skis to get around, while students in America's biggest city have been told Monday will be a remote learning day.

Similar orders are in force in other storm-affected states.

"An Arctic siege has taken over our state," said New York governor Kathy Hochul. "It is brutal, it is bone-chilling and it is dangerous."

New York communities near the Canadian border have already seen record-breaking lows, including -45C (-49F) in Copenhagen, a village in Lewis County.

Mikie Sherrill, the governor of New Jersey, announced a 35mph speed limit on highways and said she was expecting conditions the "likes of which we haven't seen in years".

In Georgia, senior state meteorologist Will Lanxton said it was "perhaps the biggest ice storm we have expected in more than a decade".

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More than 889,000 power outages were reported across the US by 12.15pm eastern time (5.15pm UK time), according to PowerOutage.us.

Tennessee was hardest hit with more than 300,000 losing their connection, while Texas, Louisiana and Mississippi all had more than 100,000 affected households.

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