Powerful snowstorm sweeps through northeast U.S.

A powerful, fast-moving storm swept through the northeastern U.S. early Thursday, disrupting air travel across the region as residents braced for blizzard conditions and more than 30 centimetres of snow.

Commuters in the densely populated region awoke to windblown snow — less than 24 hours after enjoying spring-like temperatures — and faced slick highways. Forecasters said Thursday's weather had the potential to be the most powerful storm that some areas have seen in a mostly snow-free winter.

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The National Weather Service predicted that the Boston area and eastern Maine could get 30 to 45 centimetres of snow, and a blizzard warning has been issued for all of Long Island until 6 p.m. ET, New York City could see 20 to 30 centimetres and the Philadelphia area 10 to 20 centimetres. Near whiteout conditions are possible.

The weather has disrupted air travel in the U.S. and Canada. By midday, some 3,800 flights had been delayed and about 3,400 cancelled, across the U.S. according to the website FlightAware. Those flights included dozens of delays and cancellations at Toronto's Pearson International Airport and Pierre Elliott Trudeau Airport in Montreal. 

New York City Mayor Bill de Blasio urged people to stay home.

"If you need to go out, please, don't use your car," de Blasio said on NY1 television.

In Lower Manhattan, intrepid, bundled-up commuters carefully navigated snow-covered sidewalks. The blowing snow stung any exposed skin.

Sam Lopresti, of Jersey City, New Jersey, warm and dry in his workplace, said he'd been pleasantly surprised that his early-morning train trip to Manhattan had gone smoothly.

"I fully expected the MTA and PATH to curl into a ball and say, 'Don't hurt me!"' joked Lopresti, an actor and barista.

Lopresti said weather forecasts had escalated from "a run-of-the-mill snowstorm to an apocalyptic deal."

Officials also are warning of high winds, coastal flooding and power outages.

Massachusetts, meanwhile, activated its emergency management bunker, where Gov. Charlie Baker was scheduled to provide updates on the storm at midday. Baker urged people to stay off the roads to allow plows and sanders to do their work. 

The storm started as rain early Thursday in eastern Pennsylvania and northern New Jersey before changing over to snow.

State offices were closed in New Jersey, and government offices in the Delaware, Bucks, Chester and Montgomery counties outside Philadelphia were shuttered Thursday.

A number of school systems cancelled Thursday classes including New York City, Philadelphia and Boston. Airlines scrapped thousands of flights by late Wednesday as a precaution.

The storm comes a day after much of the Northeast enjoyed a brief glimpse of spring, with temperatures hitting 15 C in some places.

Thursday's storm is expected to last six to 10 hours, said Carl Erickson, a senior meteorologist with AccuWeather in State College, Pennsylvania.

The snow is expected taper off by the early afternoon in the Philadelphia and New York City areas, but New Englanders should brace for snowfall through the evening commute.