NEW YORK (CNN) -- A massive blizzard that dumped as much as 3 feet of snow in parts of the Northeast is heading out to sea, as workers across New York and New England struggle to get airports, trains and highways back online.
The snowstorm, a product of two converging weather systems, knocked out power for more than 635,000 customers and prompted the U.S. Postal Service to suspend deliveries in seven states. About 4,800 flights were canceled as of Saturday.
At least four people died in traffic accidents related to the storm in New York, Connecticut and southern Ontario, authorities said. A 49-year-old man died while shoveling out his car in Connecticut. Firefighters were unable to resuscitate an 11-year-old boy in Boston who suffered carbon monoxide poisoning.
Mandatory evacuations were issued Saturday morning for Massachusetts coastal regions near the town of Hull because of flooding concerns, and high winds whipped throughout the region. Authorities advised residents to leave shoreline areas in Marshfield and Scituate.
Forecasters say the storm is still swirling across eastern New England with gusts up to 40 mph in cities that include Providence, Rhode Island, and Boston.
A travel ban across Rhode Island, Connecticut and Massachusetts is set to be lifted at 4 p.m. as most of the heavy snow is expected to taper off.
While the blizzard did not fulfill record-breaking predictions, travel throughout the region remained slow-going.
Hundreds of cars were stranded on the Long Island Expressway in New York after motorists got stuck driving in the snow. They outnumbered the tow trucks and crews deployed to the area for the storm, according to the Suffolk County police.
Postal worker Karlene Calliste left her job around 3 p.m. Friday, got caught in the storm and ended up sleeping at a firehouse in Middle Island, New York, where dozens of other stranded residents were holed up.
"It's crazy. They weren't prepared," she said, adding that a lack of snow plows contributed to the scores of cars and trucks left stuck in the snow.
Three of New York's busiest airports resumed limited service Saturday morning. Logan International Airport in Boston and Bradley International Airport in Windsor Locks, Connecticut, remained closed.
Snow piles up; power goes out
Connecticut saw the most accumulation, with up to 38 inches in Milford. At its height, the storm heaped snow on the state at a frenzied rate of 4 to 5 inches an hour.
iReporter Scott Green posted a photo of his deck in Cromwell -- covered waist-high with snow.
In Massachusetts, Worcester and Boston received 27 and 21 inches, respectively, with winds howling up to a hurricane-strength 75 mph.
Snowfall in Manhattan reached just under a foot, with heavier accumulations in Long Island, where 27 inches fell in Stony Brook.
"This state had consequences, but nothing like our neighboring states," said New York Gov. Andrew Cuomo. He announced Saturday plans to send utility workers and snow plows to New England to help with recovery in harder hit areas.
Rhode Island Gov. Lincoln Chafee Saturday ordered all non-emergency vehicles off the streets Saturday so snowplows could clear roadways.
Snowfall blanketed an area from eastern Pennsylvania to Maine, with overnight lows under 20 degrees as governors in six states declared states of emergency.
The storm knocked out power to more than 400,000 addresses there, accounting for nearly two-thirds of all power outages, according to Massachusetts power companies.
Electricity dropped out at a nuclear power plant in Plymouth, Massachusetts, said fire spokesman Ed Bradley, but backup generators sprang into action.
Plymouth is 90% in the dark, and most of the power outages in Massachusetts have hit the southeast part of the state.
Rhode Island may have seen the worst outages relative to its size, with more than 180,000 customers without power. At 1 million residents, it has only one-sixth the population of Massachusetts, according to the U.S. Census Bureau.
Roads turn deadly
In Poughkeepsie, New York, an 18-year-old woman lost control of her car in the falling snow and struck a 74-year-old man walking near the side of the road, police said. He later died from his injuries.
Similar accidents occurred in Prospect, Connecticut and southern Ontario.
Massachusetts, Connecticut and Rhode Island ahead of the storm ordered all non-emergency vehicles off the streets under threat of imprisonment and fines -- up to a year in jail and $500 in Rhode Island.
Rail transportation came to a virtual halt, with commuter trains running on a patchwork schedule.
Hoops snowed out
The nor'easter has swatted down travel arrangements for pro basketball teams headed to New York City, leaving the New York Knicks, San Antonio Spurs and Brooklyn Nets grounded.
Canceled flights forced the Nets to attempt to get home by train from Washington after a game there against the Wizards.
The San Antonio Spurs, who were originally flying to New York to play the Brooklyn Nets on Sunday night, are stuck in Detroit.
CNN's AnneClaire Stapleton, Pauline Kim, Jake Carpenter, Greg Botelho, Chris Boyette and Marina Carver contributed to this report. David Ariosto is in New York and Ben Brumfield is in Atlanta.
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