All non-essential travel has been banned in New York, transport suspended and bridges shut as the city is hit by one of its worst snowstorms.
Parts of the eastern United States have received 71cm (28in) of snowfall in a huge blizzard that is sweeping across the region.
Travel restrictions in New York came into place at 14:30 (19:30 GMT).
Mayor Bill de Blasio said up to 25in snow may fall, making it one of the five worst winter storms in the city.
Heavy snow began falling on Friday across more than 20 states, affecting some 85 million people.
At least 11 people have died and emergencies declared in 11 states.
Tens of thousands of homes are without power. Traffic jams lasting more than 12 hours have been reported in Kentucky and Pennsylvania.
Why do so many people die shovelling snow?
The nation’s capital, Washington, could lie under a record 30in (76cm) of snow by the time the storm passes on Sunday. At the White House, 13in (33cm) of snow fell overnight.
The heaviest snowfalls recorded so far (up to 09:00 eastern time, 14:00 GMT) include:
- 28in (71cm) – Terra Alta, West Virginia
- 24in (61cm) – Philippi, West Virginia; Oakland, Maryland
- 23in (58cm) – Ridgeley, Maryland; Champion and Marklesburg, Pennsylvania
The weather system affects a huge swathe of the country, from Alabama in the south to Massachusetts in the north-east.
In the latest developments in New York:
- Almost all flights into New York have been cancelled, according to flightaware.com
- Emergency vehicles and workers carrying out repairs will be allowed to use roads – but those driving non-essential vehicles risk being arrested
- Governor Andrew Cuomo said above-ground rail services would be suspended from 16:00 local time (21:00 GMT)
- Mr Cuomo, who declared a state of emergency on Saturday, warned some rail lines were already freezing over
- All Broadway shows on Saturday are cancelled, Mr de Blasio announced
- In a news conference, Mr de Blasio urged citizens to get off the road. “This is bad and getting worse rapidly,” his office tweeted.
“This is going to be one of those generational events, where your parents talk about how bad it was,” said Ryan Maue, a meteorologist with WeatherBell Analytics.
In Kentucky, a 35-mile (56km) traffic jam is clearing, after thousands of drivers found themselves stranded overnight on Interstate 75 by heavy snow and a number of accidents.
The Red Cross erected shelters along the highway. Kentucky State Police tweeted that officers were taking water, fuel and snacks to the motorists, some of whom had been stuck for more than 12 hours.
Further north, on the Pennsylvania Turnpike, a number of other vehicles have been stuck in snow for more than 12 hours after the road closed. One university basketball team that was stranded said they were running out of leftover pizza and getting hungry.
In other developments:
- More than 4,300 flights have been cancelled in the eastern US on Saturday alone
- Nine people have been killed in car crashes in North Carolina, Virginia, Kentucky and Tennessee
- In Virginia alone, state police reported 989 car crashes up to Friday night
- One man died on Saturday of an apparent heart attack while shovelling snow in Maryland
- More than 150,000 properties lost power in North Carolina
- Another 90,000 people are without power in New Jersey, governor Chris Christie said
- High tides in New Jersey – higher than those during Superstorm Sandy – have led to some heavy flooding in the south of the state, but the worst has now passed, Mr Christie said
- States of emergency have been declared in New York, Tennessee, Georgia, Kentucky, North Carolina, New Jersey, Virginia, West Virginia, Maryland, Pennsylvania, the District of Columbia
The US federal government closed down at noon on Friday. President Obama is remaining at the White House.
The National Weather Service (NWS) warned that the worst of the snow would fall in the Washington area from the early hours of Saturday to the early afternoon, with winds of more than 50mph (80kph).
In a warning at 02:17 (07:17 GMT), the NWS tweeted that an “intense snow band” was moving through the area. “Expect rapid accumulations and near-whiteout conditions,” it warned.
The most intense parts of the snowstorm are heading north towards New York state on Saturday.
Residents in the capital and surrounding suburbs in Virginia and Maryland have been warned the snowfall could eclipse the district’s record of 28in that fell during a two-day period in 1922.
Some tips on surviving a snowstorm
- Make sure you have at least three gallons (13.5 litres) of drinking water per person, per day
- Tape the windows with bubble wrap to keep the heat in
- Use your dog to measure the snowfall
How to prepare for a snowstorm
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