A wave crashes over a house after flooding and surge due to a winter nor'easter storm in Marshfield, Massachusetts, U.S. in this still image from video taken on March 3, 2018 obtained from social media. Instagram/JAMES KUKSTIS/via REUTERS

(Reuters) - Some 500,000 customers remained without power throughout the eastern United States on Sunday evening and New England coastal communities faced more flooding two days after a powerful storm snapped trees, downed wires and killed at least nine people.

The remnants of the storm, known as a nor’easter, lingered on Sunday, with the National Weather Service posting coastal flood advisories in effect until Monday morning in much of the U.S. Northeast even after the storm had passed.

Some half a million customers still lacked power, according to data provided by 10 major utilities in the Middle Atlantic, Midwest and Northeast. At one point, 2 million customers had lost power.

The brunt of the storm hit on Friday, packing hurricane-force winds in excess of 90 miles per hour (145 kph) and sending seawater churning into streets in Boston and nearby shore towns, marking the second time the area had been flooded this year.

Falling trees killed seven people in Connecticut, Maryland, New York, Pennsylvania, Rhode Island and Virginia, according to local media and police. Two others died in the storm, according to media reports, including a 41-year-old man in Andover, New Jersey, who came in contact with power lines.

Private forecasting service AccuWeather said the storm dumped as much as 18 inches (46 cm) of snow on parts of New York state and Pennsylvania. The Massachusetts town of East Bridgewater received nearly 6 inches (15 cm) of rain, the NWS said.

The storm also snarled transportation from the Middle Atlantic into New England, with more than a quarter of flights in and out of New York’s three major airports and Boston’s airport canceled on Friday, tracking service FlightAware.com reported.

The problems carried over into Saturday, with hundreds of flights canceled into and out of New York and Boston, according to the website.

One flight landing at Washington’s Dulles International Airport on Friday experienced turbulence so rough that most passengers became sick and the pilots were on the verge of becoming ill, the Federal Aviation Administration said.