Construction cranes stand on the World Trade Center site on Aug. 26, 2011 in New York. The Port Authority of New York and New Jersey said Friday it is securing all cranes and other construction equipment at the site due to Hurricane Irene.
Even if the winds aren't strong enough to damage buildings in a metropolis made largely of brick, concrete and steel, a lot of New York's subways and other infrastructure are underground, making them subject to flooding.
New York's two airports are close to the water and could be inundated, as could densely packed neighborhoods, if the storm pushes ocean water into the city's waterways, officials said. In 2008, the city had a brush with Tropical Storm Hanna, which dumped 3 inches of rain on Manhattan.
In the last 200 years, New York has seen only a few significant hurricanes. In September 1821, a hurricane raised tides by 13 feet in an hour and flooded all of Manhattan south of Canal Street, the southernmost tip of the city. The area now includes Wall Street and the World Trade Center memorial.Complete coverage: Hurricane IreneNational Hurricane Center