A rare, powerful spring nor'easter storm along the U.S. East coast has cut power to more than 50,000 customers in Pennsylvania and upstate New York, according to reports.

Utility companies have been bracing for the storm because of the threat of flooding rains, snow and wind with potential to down power lines.

On Sunday, FirstEnergy Corp., which owns several companies, some of which provide services to areas of western Pennsylvania, Maryland and West Virginia, announced that it was already mobilizing its employees and resources to restore power to customers who may be affected by the storm.

The energy company was also securing additional outside utility crews and tree contractors to help with the process of outage restoration.

Monday's expected wet snow and high winds have the potential to cause damage to the electrical system, especially since many trees already have leaves due to an unseasonably warm spring, a release from the energy company stated. Heavily weighted branches, limbs and entire trees may fall, taking down power lines and snapping utility poles.

According to the Wall Street Journal, natural gas futures edged higher Monday after the heavy storm. The natural gas for May delivery recently rose 3 cents, or 1.6 percent, to $1.957 a million British thermal units on the New York Mercantile Exchange.

More snow is expected during the day; weather.com reported that morning rain is expected to change to several inches of snow in Buffalo. Moreover, parts of the Allegheny Plateau and the Appalachians could see at least a foot of snow.

The National Weather Service said because of the rare late-April winter storm, flood watches are in effect for parts of central New Hampshire into eastern Maine. There are also flood advisories in effect for eastern Massachusetts.

Winter storm warnings are in effect from the higher elevations of West Virginia northward to Western New York State, NWS said.

Weather.com reported that early Monday morning, 10 inches of snow was reported in Newfield, in western New York, while five inches fell in Boswell, Pa.

Some schools were closed in western Pennsylvania.

The arrival of the storm on Sunday caused the postponement of the Boston Red Sox night game against the New York Yankees. Similarly, the scheduled arrival of the space shuttle Enterprise for museum display in New York City was pushed back.

The last time a big snowstorm hit so late in the season was 1928, Aaron Tyburski, a National Weather Service meteorologist in State College, Penn., told the Los Angeles Times.