The northeast of the United States crawled out from under a mammoth blizzard Sunday that caused at least nine deaths and paralyzed the region with high winds and heaps of snow.

More than 300,000 customers were still without power in the wake of the storm that struck a slew of states and dumped as much as three feet of snow across New England before battering three Canadian provinces.

The majority of the service disruptions were in hard hit Massachusetts, where Governor Deval Patrick said outages were at 250,000, down from 400,000 Saturday.

PICTURES: Blizzard Nemo Slams Into U.S. East Coast

As crews worked to clear roads and sidewalks, travel conditions in the area began to pick up and return to normal.

New York area airports LaGuardia, John F Kennedy and Newark, which halted all flights at the height of the storm, resumed service Saturday with some delays.

Boston's Logan International Airport meanwhile warned travelers Sunday it was still experiencing some weather-related delays and cancellations., which on Saturday listed almost 2,000 cancellations around the area, said 89 flights were scrapped at Logan, compared to 13 at JFK, two each at LaGuardia and Newark and 13 at Canada's Halifax Stanfield International Airport.

Logan "opened at 11 am and flights will be rebuilding by the end of today," said spokesman Matthew Brelis. "All 22 international airlines will come in and out tonight."

PICTURES: Wild Winter Weather

Rail company Amtrak, meanwhile, announced it would restore limited service between New York and Boston as it continued to clear its tracks of deep snow and downed trees and make the necessary repairs to restore full train service in the Northeast.

To facilitate the cleanup efforts, President Barack Obama signed an emergency declaration for the state of Connecticut Sunday, where Governor Dannel Malloy said it appeared that most, if not all counties had been hit with record or near record snowfall.

"This declaration will provide much needed assistance to the state and our towns and cities as we continue to recover from this historic winter storm," Malloy said.

Some 16,620 customers remained without power in the state, according to Connecticut Light & Power.

As a thousand people in Massachusetts sought relief in shelters, Patrick said a major challenge, aside from cleaning up and restoring power, was making sure public transportation was back up and running by Monday morning.

A tree and stret sign are covered in snow following a powerful blizzard on Feb. 9, 2013 in Boston, Massachusetts. The storm knocked out power to 650,000 and dumped more than two feet of snow in parts of New England.Getty

"We're trying to make sure that public transit is fully functioning in time for tomorrow's commute," he told broadcaster CBS.

Limited bus and subway service in Boston was expected to resume in the early afternoon but operators called on its customers to expect significant delays at the start of the new workweek.

PICTURES: Blizzard Nemo Slams Into U.S. East Coast

Meanwhile, a spokeswoman for the National Grid power company said it was warning some of its customers in the southeast of the state that they may not have electricity restored before Tuesday.

"It's a possibility," said Charlotte McCormack, adding that some 72,000 of its customers remained without power in Rhode Island.

"We took a very major blow, but the state's responding very well," said Rhode Island Senator Jack Reed.

The storm also took a human toll.

A Massachusetts boy aged 11 died when he and his father were warming up in their car and inhaled carbon monoxide after an exhaust pipe had been blocked by snow.

A car driven by a young woman went out of control in the snow on a highway in the town of Poughkeepsie, New York, striking and killing a 74-year-old man who was walking on the shoulder of the road.

And in Auburn, New Hampshire, a man was killed after losing control of his car and hitting a tree, local officials said.

PICTURES: Wild Winter Weather

Malloy was quoted by local media as saying there were five storm-related deaths in Connecticut and, according to reports, a fatal crash in Maine claimed another life.

Minor injuries were reported in a 19-car pileup on Interstate 295 in Falmouth, Maine, caused by poor visibility and slippery road conditions.

The storm came a little over three months after Hurricane Sandy devastated swaths of New York and New Jersey, killing 132 people and causing damage worth some $71.4 billion.

As the East Coast slowly dug out, the National Weather Service warned of a new blizzard taking aim at the northern plains.

"A blizzard will continue across the north central US, where heavy snow will combine with strong gusty winds to produce dangerous whiteout conditions," it said.