US digs out of snow while Canada braces for more
The eastern US has begun digging out from a storm that dumped 19in (48.3cm) of snow in New York City and parts of the state of New Jersey.
Warmer temperatures eased the clean-up in Washington DC, although schools there, in New York and in Canada's Maritime provinces were closed.
Travellers were stranded and 300,000 homes lost power around the capital.
As the storm moved north-east, the Maritime provinces on Thursday braced for as much as 30cm of snow in places.
'Rare' snow day
Two of America's largest airports - Newark, in New Jersey, and John F Kennedy, in New York City - reopened on Thursday after closing their doors on Wednesday evening.
Also in New York, city government offices were closed on Thursday.
"New York City almost never takes a snow day, but today is one of those rare days," Mayor Michael Bloomberg said in a statement.
"People should stay at home and off the roads. There are extensive service delays on mass transit, including a suspension of all bus services."
The city, which typically sees 21in of snow per season, had already seen 36in this winter prior to Wednesday night's storm.
New York declared a weather emergency for the second time since a storm on 26 December trapped hundreds of buses and ambulances.
In Philadelphia, 150 buses were stuck throughout the evening on Wednesday, with some passengers choosing to spend the night on some of them, according to local transportation officials.
Parts of Washington DC experienced a mixture of sleet and snow along with thunder and lightning, in an unusual phenomenon known as "thundersnow".
Washington's legions of federal government workers were allowed to come into the office up to two hours late, take unscheduled holiday, or work from home.
Roughly 300,000 people around the nation's capital were left without power following the storm.
On Wednesday night, US President Barack Obama's return to the White House from a trip to Wisconsin was affected after the weather grounded the helicopter that typically takes him into the capital from the military base where his Air Force One aircraft lands.
Mr Obama was met by his motorcade which spent an hour weaving through stalled rush-hour traffic on a journey that normally takes about 20 minutes.
Washington commuters were forced to contend with snow-stranded public transport buses and abandoned cars.
"My neighbourhood was spooky, no lights, no power but downed trees and powerlines," local ABC television journalist Gail Pennybacker reported after her typically 75-minute commute lasted seven hours.
BBC reporter Franz Strasser captured video footage of a traffic jam caused by the winter storm in north-west Washington on Wednesday evening.
It has snowed so much in the town of Portsmouth, New Hampshire, this winter that clean-up crews are running out of places to move ploughed snow.
Portsmouth public works director David Allen told the Associated Press that the snow dump on nearby Pierce Island was already about five storeys high.
"It's time to get a lift up on it and we could probably do a ski run," he joked.