New York: A winter storm has dumped nearly 58 centimetres of snow on Washington, DC, before moving on to Philadelphia and New York, paralysing road, rail and airline travel along the US east coast.
At least 10 states declared weather emergencies on Saturday, aiming to get a handle on highways made impassable by the drifting snow and to shore up coastal areas where the blizzard conditions raised the danger of flooding.
US snow storm one of the worst in history
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A winter storm that dumped heavy snow on the US capital continues to head up the East Coast, bringing blizzard conditions and the threat of flooding.
High winds battered the region, reaching 110 km/h in Wallops Island, Virginia, late on Friday, said meteorologist Greg Gallina of the National Weather Service.
High tides washed through the streets of Jersey Shore towns, mixing with snow and pooling in driveways.
Video footage on CNN showed water pouring into downtown Margate, New Jersey, near Atlantic City, an area still recovering from Superstorm Sandy three years ago.
The heaviest snow was engulfing New York City on Saturday but was expected to ease by early afternoon, though not end until Sunday.
Officials throughout the region pleaded with residents to stay off roads. But few put it as forcefully as New York.
"Stay off the road," the New York City Police Department said in a tweet. "We don't want to have to arrest you."
New York City also halted above-ground subway service and buses Saturday afternoon; the buses were expected to resume on Sunday morning, but it was unclear late Saturday when the trains would run again.
States of emergency were declared in at least 10 states: Delaware, Georgia, Kentucky, North Carolina, Pennsylvania, Tennessee, West Virginia, New York, Maryland and Virginia. At least six people were killed in car crashes due to icy roads in North Carolina, Kentucky and Tennessee.
Several states spent the day grappling with power outages, with the Carolinas and New Jersey the hardest hit. As of midday Saturday, nearly 140,000 customers were without power in North and South Carolina, and nearly 49,000 in New Jersey.
Meanwhile, passengers were stranded across the region after airlines cancelled more than 10,000 flights scheduled for Friday, Saturday and Sunday, according to FlightAware.com.
Those stranded included US Vice-President Biden and his wife, Jill, whose flight from Turkey was diverted to Miami, according to the White House.
Defence Secretary Ashton Carter found himself similarly diverted, to Tampa, on his return from a trip to Davos, Switzerland. Not even the Pentagon's powerful "doomsday plane" on which Mr Carter flies - which can withstand fallout from a nuclear bomb - was risking the storm.
But few could top the ordeal in Kentucky, where several thousand motorists became stranded overnight when icy conditions closed a 50-kilometre stretch of highway for more than 13 hours on Friday night and Saturday morning.
Traffic on Interstate 75 ground to a halt, authorities said, after large trucks were unable to get up steep hills and cars started slipping and sliding. But no injuries were reported.
An indie band began serenading fellow drivers on the roadway and uploaded an impromptu song about the experience to YouTube, recorded from inside their RV.
The worst appeared to be over for Washington, although moderate snow was expected to keep falling until late Saturday, with the deepest accumulation of 58 centimetres recorded in Poolesville, Maryland, north of the nation's capital.
"Records are getting close - we're getting into the top five storms," Gallina said.
The record high of 71 centimetres of snow in the nation's capital was set in 1922 and the deepest recent snowfall was 45 centimetres in 2010.
Many stores were left with bare shelves as residents stocked up on food, water and wine, preparing to spend the weekend indoors.
Reuters, Bloomberg, Washington Post