Wind gusts of up to 79 miles per hour were reported at John F. Kennedy International Airport at around 9 p.m EDT.
The storm surge was reaching as high as 13.7 feet around 9 p.m. EDT at the Battery in New York City, which was threatening flooding throughout the city's Financial District. The New York Stock Exchange on Wall Street is located near the Battery.
The center said that tropical-storm-force winds were expected to continue north of Chatham, Mass. through much of New England and south of Chincoteague, Va. Hurricane-force wind gusts were expected in these areas.
The National Hurricane Center said the center of Sandy would move across Pennsylvania during the next day or so and then move into western New York on Tuesday night.
A blizzard has also moved into regions of the Appalachians. Up to 10 inches of snow have fallen as far south as Newfound Gap, Tenn., according to weather.com. Forecasts suggest that areas above 2000 feet in the region could receive more than 1 foot of snow, and more than 2 feet of snow at elevations of more than 4000 feet.
The National Hurricane Center said it forecast a steady weakening of the storm during the next 48 hours.
-- Written by Joe Deaux in New York.