New York/Washington: A winter storm dumped nearly 2 feet (58 cm) of snow on the suburbs of Washington, DC, on Saturday 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, 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.
High winds battered the region, reaching 70 miles per hour 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, televised images showed.
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.
At least six people were killed in car crashes due to icy roads in North Carolina, Kentucky and Tennessee.
The worst appeared to be over for Washington, although moderate snow was expected to keep falling until late Saturday, with the deepest accumulation of 23 inches 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 28 inches (71 cm) of snow in the nation's capital was set in 1922 and the deepest recent snowfall was 17.8 inches in 2010.
Many stores were left with bare shelves as residents stocked up on food, water and beverages, preparing to spend the weekend indoors.
The governors of New Jersey, Pennsylvania, Maryland, Virginia, North Carolina, Georgia, Delaware, West Virginia, Tennessee, Kentucky, and the mayor of Washington, declared states of emergency.
Officials warned people not to drive.
The storm developed along the Gulf Coast, dropping snow over Arkansas, Tennessee and Kentucky on Friday.
On the East Coast, warm, moist air from the Atlantic Ocean collided with cold air to form the massive winter system, meteorologists said.
The storm was forecast to move offshore in southern New England early next week.
Philadelphia and New York were expected to get up to 18 inches of snow before the storm abated.
Low-lying areas of New York and New Jersey might see flooding during high tides on Saturday and Sunday, officials said.
More than 4,200 US flights were cancelled on Saturday, most of them at airports in New York, Philadelphia and Washington, according to tracking website FlightAware.com.
Amtrak modified service on train routes along its busy Northeast Corridor and New Jersey Transit shut all bus, rail and light rail service early on Saturday and said it would restore service as "conditions permit."
The Washington Metropolitan Area Transit Authority, which includes the country's second-busiest subway system, took the rare step of suspending operations from late Friday through Sunday.