According to the United States Landfalling Hurricane Probability Project:
16% probability that NY City/Long Island will be hit with a tropical storm or hurricane in 2009. Normal value is 15%.
10% probability that NY City/Long Island will be hit with a hurricane in 2009. Normal value is 9%.
http://www2.sunysuffolk.edu/mandias/38hurricane/hurricane_future.html5% probability that NY City/Long Island will be hit with a major hurricane (category 3 or more) in 2009. Normal value is 4%.
>99.9% probability that NY City/Long Island will be hit with a tropical storm or hurricane in the next 50 years.
99.4% probability that NY City/Long Island will be hit with a hurricane in the next 50 years.
90% probability that NY City/Long Island will be hit with a major hurricane (category 3 or more) in the next 50 years.
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Experts now believe that after Miami and New Orleans, New York City is considered the third most dangerous major city for the next hurricane disaster. According to a 1990 study by the US Army Corps of Engineers, the city has some unique and potentially lethal features. New York's major bridges such as the Verrazano Narrows and the George Washington are so high that they would experience hurricane force winds well before those winds were felt at sea-level locations. Therefore, these escape routes would have to be closed well before ground-level bridges (Time, 1998). The two ferry services across the Long Island Sound would also be shut down 6-12 hours before the storm surge invaded the waters around Long Island, further decreasing the potential for evacuation.
A storm surge prediction program used by forecasters called SLOSH (Sea, Lake, and Overland Surge from Hurricanes) has predicted that in a category 4 hurricane, John F. Kennedy International Airport would be under 20 feet of water and sea water would pour through the Holland and Brooklyn-Battery tunnels and into the city's subways throughout lower Manhattan. The report did not estimate casualties, but did state that storms "that would present low to moderate hazards in other regions of the country could result in heavy loss of life" in the New York City area (Time, 1998).
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