The National Weather Service issued winter storm warnings from West Virginia northward into western New York, a flood watch for central New Hampshire and eastern Maine and flood advisories for eastern Massachusetts.

As much as 12 to 18 inches (30 to 45 cm) of snow could fall in the mountains of West Virginia and western Pennsylvania, the service said. A foot of snow was reported in Laurel Summit in southwestern Pennsylvania, it said.

The storm caused scattered power outages in several states, as trees and power lines fell, particularly in New York and Pennsylvania. About 57,000 power outages were reported from Kentucky to Maine.

"The wet, heavy snow could bring down tree limbs and cause power outages, given the early leafing of trees this season," the weather service said on its website.

After a milder-than-normal winter in most of the country, the snow began falling late Sunday from the mountains of West Virginia to the southern shores of Lake Erie in Pennsylvania and New York.

Near Buffalo, New York, predicted snowfall amounts ranged from 2 to 3 inches (5 to 7.5 cm) along Lake Erie to a foot (30 cm) or more in the hills south and west of the city, the weather service said.

Authorities reported tree limbs and power lines down along the southern Lake Erie shoreline, where another six to eight inches (15 to 20 cm) was expected by nightfall as part of the rare spring storm expected to last until Tuesday morning.

"Once you get to the four-inch (10 cm) mark you start to see power outages," said Tony Ansuini of the National Weather Service in Buffalo.

New York State Police said reports of cars off the road and downed trees and branches were coming in from counties south of Buffalo.

"It's been non-stop," State Police Trooper John Dycha said of the snow, although he said only property damage had been reported.

The weather and a low cloud ceiling caused delayed departures at Newark International Airport and Philadelphia International Airport, according to the Federal Aviation Administration.

Winds were gale-force in Atlantic waters off New England and gusting as much as 50 miles (80 km) per hour along the coastal Northeast, according to the weather service, which issued a wind advisory for Cape Cod and other parts of eastern Massachusetts.

"Snow will continue to fall across areas from West Virginia to western New York today and into tonight before beginning to slowly taper off by Tuesday morning," the weather service said. "In New England, widespread moderate to heavy rain will continue to fall before tapering off from south to north tonight."

Colder temperatures and moisture will likely bring more snow accumulation in parts of northwestern Pennsylvania and upstate New York, said AccuWeather meteorologist Alex Sosnowski.

"The snow will tend to retreat northward out of West Virginia, northwestern Virginia, western Maryland and southwestern Pennsylvania this afternoon and tonight," he said.

(Reporting by Dan Burns, Daniel Lovering and Ellen Wulfhorst; Editing by Doina Chiacu)

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