Without power, the hospital had no elevator service, meaning patients had to be carefully carried down staircases.
Earlier Monday, another 1 million customers lost power in New York City, the northern suburbs and coastal Long Island, where floodwaters swamped cars, downed trees and put neighborhoods under water.
The storm had only killed one New York City resident by Monday night, a man who died when a tree fell on his home in the Flushing section of Queens.
The rains and howling winds, some believed to reach more than 95 mph, left a crane hanging off a luxury high-rise in midtown Manhattan, causing the evacuation of hundreds from a posh hotel and other buildings. Inspectors were climbing 74 flights of stairs to examine the crane hanging from the $1.5 billion building.
The facade of a four-story Manhattan building in the Chelsea neighborhood crumbled and collapsed suddenly, leaving the lights, couches, cabinets and desks inside visible from the street. No one was hurt, although some of the falling debris hit a car.
On coastal Long Island, floodwaters swamped cars, downed trees and put neighborhoods under water as beachfronts and fishing villages bore the brunt of the storm. A police car was lost rescuing 14 people from the popular resort Fire Island.
The city shut all three of its airports, its subways, schools, stock exchanges, Broadway theaters and closed several bridges and tunnels throughout the day as the weather worsened.
Earlier, some New Yorkers defiantly soldiered on, trying to salvage normal routines and refusing to evacuate, as the mayor ordered 375,000 in low-lying areas to do.
Tanja Stewart and her 7-year-old son, Finn, came from their home in Manhattan's TriBeCa neighborhood to admire the white caps on the Hudson, Finn wearing a pair of binoculars around his neck. "I really wanted to see some big waves," he said.
Keith Reilly posed in an Irish soccer jersey for a picture above the rising waters of New York Harbor with the Statue of Liberty in the background.
"This is not so bad right now," said the 25-year-old Reilly.
On Long Island, floodwaters had begun to deluge some low-lying towns. Cars floated along the streets of Long Beach and flooding consumed several blocks south of the bay, residents said.
Gov. Andrew Cuomo, holding a news conference on Long Island where the lights flickered and his mike went in and out, said most of the National Guards deployed to the New York City area would go to Long Island.
Anoush Vargas drove with her husband, Michael to the famed Jones Beach Monday morning, only to find it covered by water.
"We have no more beach. It's gone," she said, shaking her head as she watched the waves go under the boardwalk.
Associated Press writers Karen Matthews, Colleen Long and Deepti Hajela in New York, Larry Neumeister, Frank Eltman and Meghan Barr on Long Island, and Seth Borenstein in Kensington, Md., contributed to this report.
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