The storm that slammed into the region with up to 3 feet of snow was blamed for at least 15 deaths in the Northeast and Canada.
The storm, spawned by the collision of two weather systems, affected more than 40 million people and delivered some of the highest accumulations of snow ever recorded.
Still, coastal areas were largely spared catastrophic damage despite being lashed by strong waves and hurricane-force wind gusts at the height of the storm.
Hundreds of people, their homes without heat or electricity, were forced to take refuge in emergency shelters set up in schools or other places.
Utility crews, some brought in from as far away as Georgia, Oklahoma, and Quebec, raced to restore power to more than 220,000 customers — down from 650,000 in eight states at the height of the storm.
In hardest-hit Massachusetts, where about 180,000 customers remained without power on Sunday, officials said some of the outages might linger until Tuesday.
Driving bans were lifted and flights resumed at major airports in the region that had closed during the storm. But many flights were canceled Sunday.
The Boston-area public transportation system, which shut down on Friday afternoon, partially resumed subway service and some bus routes on Sunday.
Boston public schools were among many in the region that had decided to cancel classes today.
Boston recorded 24.9 inches of snow, making it the fifth-largest storm in the city since records have been kept.
The city was appealing to the state and private contractors for more front-end loaders and other heavy equipment to clear piles of snow that were clogging residential streets.
On eastern Long Island, which was slammed with as much as 30 inches of snow, hundreds of snowplows and other heavy equipment were sent in to clear ice and drift-covered highways, where hundreds of cars were abandoned during the height of the storm.
Hundreds of cars were stuck on roads, including the Long Island Expressway, a 27-mile stretch of which was closed Sunday for snow-removal work.
Officials hoped to have most major highways cleared in time for today’s morning commute.
More than a third of all the state’s snow-removal equipment was sent to the area, Gov. Andrew Cuomo said, including more than 400 plow trucks and more than 100 snow blowers, loaders, and backhoes.
Of greatest concern were flat or gently sloped roofs, and officials said people should try to clear them — but only if they could do so safely.
“We don’t recommend that people, unless they’re young and experienced, go up on roofs,” said Peter Judge, spokesman for the Massachusetts Emergency Management Agency.
Officials also continued to warn of carbon monoxide dangers in the wake of the storm.
In Boston, two people died Saturday after they were overcome by carbon monoxide while sitting in running cars, including a teenager who went into the family car to stay warm while his father shoveled snow.
The boy’s name was not made public.
In a third incident, two children were hospitalized but expected to recover.
A fire department spokesman said in each case, the tailpipes of the cars were clogged by snow.
Authorities also reminded homeowners to clear snow from heating vents to prevent carbon monoxide from seeping back into houses.
The National Weather Service said it had reports out of New Haven County, Connecticut, of 36.2 inches of snow in Oxford and 38 inches in Milford.
President Obama declared a state of emergency in Connecticut on Sunday, ordering federal aid to supplement local emergency response efforts.
Calling the storm “historic,” Connecticut Gov. Dannel Malloy praised the President’s decision and pressed residents to stay out of the way of emergency crews until the snow was cleared.
“While the ban on travel has been lifted, we are continuing to urge residents to stay off the roads, if at all possible,” Mr. Malloy said.
In Massachusetts, eight teams were formed to assess damage from flooding along the state’s coastline, with the hardest-hit areas including historic Plymouth and portions of Cape Cod.
“Considering the severity of the storm, the amount of snow, and the wind, we’ve come through this pretty well,” Massachusetts Gov. Deval Patrick told CBS’s Face The Nation after meeting with local officials in Plymouth.
The U.S. Postal Service said that mail delivery that was suspended in the six New England states, as well as parts of New York and New Jersey, because of the snowstorm would resume Monday, where it is safe to do so.
Amtrak announced that it had resumed limited service between New York and Boston.