More than 4,400 flights were cancelled as the mega-storm ground airports in New York, Philadelphia, Washington and Baltimore to a halt, shuttered transport in the US capital and prompted New York officials to issue a sweeping travel ban.
At least 10 people died in North Carolina, Maryland, Kentucky and Virginia, while more than 200,000 people were left without power and 2,200 National Guard personnel were drafted in across 12 states.
Forecasters said the storm -- dubbed "Snowzilla" -- would last into Sunday with two feet (60 centimeters) expected in Washington and 20 inches expected in New York, making it one of the Big Apple's five biggest blizzards in history.
State Governor Andrew Cuomo closed all roads in New York, America's financial and entertainment capital home to 8.4 million, Long Island, and bridges and tunnels west to New Jersey.
Bus services were suspended at noon, and overland commuter and subway trains in and out of Manhattan were shut from 4:00 pm (2100 GMT) as Broadway cancelled performances, museums closed and shops shuttered.
Metro and bus networks were shut down in Washington for the entire weekend, and largely shut in Philadelphia and New Jersey on Saturday.
Strong winds are causing coastal flooding concerns for a large portion of the East Coast, the National Weather Forecast (NWS) warned, and thousands of motorists were stranded for hours on portions of ice-coated highway in the south.
- 'Dangerous storm' -
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"Safety is our number one priority," Cuomo told reporters. "This is a dangerous storm. As beautiful as some of the photos are of the snow falling. It's dangerous," he told CNN.
Plows struggled to clear Manhattan's sweeping avenues, where parked cars were buried under the snow and people coming out to enjoy the weather walked in place of normally bustling traffic.
"It has been very slow in the morning, but I hope people will get tired of playing with the snow and come to eat and drink something," said Juan, a barman at a restaurant in the West Village.
In Washington, more than 18 inches (45 centimeters) of snow was already on the ground, with winds swirling and snow blowing around as night fell.
City police chief Cathy Lanier said whiteout conditions -- virtually zero visibility -- had been reported and urged residents to stay indoors so snow plows could work to clear the streets.
One resident of the capital having a blast in the snow? Tian Tian, a panda at the National Zoo. Footage of him playing in the snow quickly went viral.
The NWS put a blizzard warning into effect for a large swath of the eastern United States, as hundreds of snow plows and salt spreaders struggled to clear key avenues.
The storm could cause more than $1 billion in damage, NWS officials said.
New Jersey Governor Chris Christie, a Republican presidential contender, left the campaign trail to oversee the emergency response in his snowbound state, where he said there were 90,000 power outages.
"For folks who lose power, please, given how cold the weather is, try to go and shelter in the home of a friend or family member if you can. Don't stay in the cold," he told a news conference.
Nearly 120,000 power outages were reported in North Carolina, emergency officials said.
- Record-breaking? -
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The NWS reported that New York could see up to 25 inches of snow and that travel was extremely dangerous "due to heavy snowfall and strong winds with whiteout conditions likely."
Mayor Bill de Blasio warned that more than 20 inches would put the storm in the top five in terms of accumulation since records began in the 19th century.
If the blizzard leaves more than two feet in Washington, as forecast, it could surpass a record set in 1922 by a storm that dumped 28 inches over three days and killed 100 people after a roof collapsed at a theater.
US Capitol Police said they were lifting a decades-old sledding ban, but the national monuments, Capitol building and Smithsonian museums were all closed.
Even a massive snowball fight in Washington's Dupont Circle, which 3,000 people said on Facebook they would attend, was postponed due to the storm's ferocity.
"We just came back from some holidays in India so the weather is a difficult adjustment," said Justin Wilcox, 32, out taking selfies in the capital.
Snow and sleet also hit the southern states of Arkansas, Tennessee, Kentucky, North Carolina, West Virginia and Virginia -- unusual for the region.
Six people were killed in road accidents in North Carolina, and deaths were also reported in Kentucky, Maryland and Virginia, officials said.
Virginia state police tweeted that they responded to 989 crashes and 793 disabled vehicles across the state Friday.
- AFP