How a Major Category 3 Hurricane Would Affect New York City

After Hurricane Irene made landfall in southern New Jersey as a Category 1 Hurricane and in Brooklyn, New York as a strong Tropical Storm in August 2012, it is important to consider how a major Category 3 Hurricane would affect New York City upon making landfall in the New York City area, and what such a hurricane would do to the large coastal city and its surrounding areas.

It should be noted that while not unprecedented, a hurricane striking New York City or even within 50 miles of New York City is a rare event. The high level winds that normally blow generally from west to east over the New York City area (known as the westerlies) act as a protector of the city against direct landfalls from coastal storms, including hurricanes. However, the protective westerlies are not always present, or are sometimes tied into a knot and blow from the south or even the southeast. It is at these times that the New York City area is vulnerable to a direct hit from a hurricane. Since hurricanes rarely make it to the latitude that New York City is located at and the westerlies are usually present and strong enough to push storms to the east, statistically, a direct hurricane landfall in New York City a very small probability. An even smaller probability is a direct landfall in New York City by a major Category 3 hurricane, since these monster storms are even rarer than their less powerful cousins and rarely survive the trip to the latitude that New York City is located. But historically, major Category 3 hurricanes have made landfall in or near New York City every 70 to 90 years, with the last Category 3 hurricane impact in the New York City area being the 1938 Long Island Express hurricane that made landfall in western Suffolk County, Long Island, New York. While a very small possibility, New York City could actually take a direct hit from a major Category 3 hurricane.

While this scenario outlines the devastating effects a major Category 3 hurricane making landfall in the New York City area would have, it could apply to any major city along the east coast of the United States from Washington, DC to Boston. However, unlike other major cities on the east coast of the United States, which are protected by land masses that stand between them and the Atlantic ocean, New York City is more susceptible to a major hurricane landfall since it is situated on and very close to the Atlantic Ocean.

How a Major Category 3 Hurricane Would Affect New York City: Hurricane Impacts

Once hurricanes pass North Carolina, they lose the 80 degrees Fahrenheit and warmer water that they require to maintain their strength, and start to slowly dissipate. For a hurricane to strike New York City as a major Category 3 hurricane, the storm must have adequate strength of at least Category 3 when it passes North Carolina and it must be moving quickly at 30 miles per hour or more to make the 450 mile trip from the North Carolina coastal waters to New York City before the hurricane loses its Category 3 strength. While a fast moving hurricane causes a shorter duration of hurricane conditions over a given area, the hurricane effects can be enhanced by the fast movement of the storm, with winds and storm surges more intense, as the fast motion of the storm increases winds on the east side of the storm and build a fast moving wall of water, which is known as the storm surge.

The worst case scenario for New York City, is a fast moving Category 3 hurricane that moves into the city from Atlantic ocean from a south-southeast direction, crossing the boroughs of Brooklyn and Staten Island and then proceeding to move up New York Harbor and the Hudson River and nearby parts of New Jersey, just west of the city. This scenario would put most of New York City, including Manhattan, in the most damaging northeast quadrant of the Category 3 hurricane’s eyewall, with sustained winds between 111 and 130 miles per hour and gusts to over 150 miles per hour. The buildings in the city may even funnel the winds and increase their speeds. Needless to say, winds of this magnitude for any length of time would do major damage to many structures in the city. The streets would be filled with fast moving deadly debris, as windows burst and pieces of buildings are torn off. Perhaps the larger buildings in Manhattan would only suffer blown out windows and some wind and water damage, but many homes and buildings in the surrounding boroughs could sustain serious damage and even roof failures. Wind damage throughout the New York City area, including the suburban areas to the north and west and Long Island to the east, would be considerable. Power would be knocked out for millions of people, perhaps for weeks.

Wind would only be one of the extremely damaging effects a major Category 3 hurricane would have on New York City. An enormous storm surge of 20 feet or more would inundate low lying parts of New York City, including coastal parts of Brooklyn and Queens where JFK and LaGuardia airports are located and lower Manhattan, including the financial district. Many car and train tunnels, including major parts of the New York City subway system, would be flooded with corrosive seawater. Major highways that parallel the water, such as the East Side Drive in Manhattan, would be under water. Low lying buildings and homes in all five boroughs of New York City would be flooded and severely damaged. The wall of seawater would flood low lying parts of New Jersey along the Hudson River and low lying points north of New York City along the banks of the Hudson River (the Hudson is a tidal river all the way to Troy, New York, 160 miles north of the city). Long Island would endure a considerable storm surge, as the winds on the east side of the hurricane hurtle water over the barrier islands and into low lying parts of Long Island.

Inland from New York City, the greatest impacts from a major Category 3 hurricane would be extensive wind damage and excessive rainfall that would result in power outages and flash flooding, and possible river flooding. Even as the hurricane loses strength as it moves inland, the wind damage would be considerable, with many trees and branches knocked down and many buildings damaged. The flooding impacts from the hurricane would depend upon the speed of the storm and whether it slows down at all once it makes its way inland. But even a relatively short duration rainfall event from a fast moving hurricane can drop five to ten inches of rain in a few hours. A major Category 3 hurricane holds more moisture than less powerful hurricanes, and once that moisture starts interacting with the hilly terrain north and west of New York City, rainfall rates could increase with torrential rains filling creeks and rivers, which would cause considerable flooding and damage to roadways and buildings.

The New Jersey coastal areas, especially northern parts of the coastal areas that would be closer to the eye of the hurricane, would see significant impacts from wind, rain, and storm surge. However, the winds along the New Jersey coastal areas would blow out of the west due to their proximity to the center of the storm, which would lessen the impacts of storm surge, and the winds would not be as intense as they would be further north in the New York City area.

After the major Category 3 hurricane has passed, travel in and around New York City would be impossible in many areas, with roads blocked by fallen trees and debris or flooded, and mass transit inoperable. In the days afterwards, major river flooding could ensue inland. It would likely take weeks for mass transit networks to return to a semblance of normalcy. Parts of the New York City subway system may have to be substantially rebuilt, as corrosive seawater damages subway equipment and tunnels. Commuter rail lines may need to have much of their overhead wiring replaced. Roadways would be impacted from fallen trees and flooding that may require major repairs.

Seawater Flooding In The Hoboken PATH Underground Train Station During a 1992 Severe Noreaster

Cost of a Major Category 3 Hurricane Strike in the New York City Area

Since major Category 3 hurricanes are relatively rare in the New York City area, estimating the cost of major Category 3 hurricane is rather difficult. No two storms are the same, and the heavily populated city and surrounding areas have a tremendous amount of public and private property that could be damaged or destroyed by a major Category 3 hurricane.

Perhaps the best comparison is the 1938 Category 3 hurricane, known as the Long Island Express or Great New England Hurricane of 1938 that struck Long Island as a Category 3 hurricane approximately 50 miles to the east of New York City and continued as a substantial hurricane into New England. This Category 3 hurricane killed approximately 680 to 800 people, damaged or destroyed approximately 57,000 homes, and caused property losses estimated at $41.1 billion in 2011 dollars. While modern weather forecasting and massive evacuations may limit the loss of life if a major Category 3 hurricane hit the New York City area today, there are many millions more people now living in the New York City area than there were in 1938, so many more people could potentially be in harm’s way, especially if the storm is moving quickly and people are not able to evacuate. Also, there are many more buildings in the New York City area now than there were in 1938. The property damage from a major Category 3 hurricane that plows through the New York City area would be catastrophic, perhaps exceeding $100 Billion.

New York City’s Evacuation Plans for a Major Category 3 Hurricane

The only way to mitigate the impacts a major Category 3 hurricane would have on New York City’s population is to get people out of harm’s way. The city recently demonstrated its resolve to protect human lives and its ability to evacuate 100,000s of residents before the August 2011 hurricane Irene. This effort was commendable for such a large city; however, the evacuation zone for a major Category 3 hurricane would have to be much larger than it was for hurricane Irene (which was actually only a strong tropical storm by the time it made landfall at Coney Island, in the borough of Brooklyn). This is because the storm surge during a major Category 3 hurricane would impact a much larger area than a less powerful Category 1 hurricane. Many more people would need to be evacuated and placed into buildings that could sustain a Category 3 hurricane impact. The city has plans to use subways and buses to get people out of harms way in the event that a Category 3 hurricane is approaching; however, if the hurricane is a fast moving storm it may be impossible to get everyone out of the areas that will be impacted by the enormous storm surge.

It is not a matter of if, but when, a major Category 3 hurricane will make a direct landfall in New York City and cause major devastation to the mid-latitude city. The City of New York and its surrounding areas would be wise to have contingency plans in place to deal with this natural disaster threat. New York City has experienced a lot of bad storms over the years; however, a major Category 3 hurricane landfall in the city that put the city in the strongest part of the storm would produce damage that the city may have never witness in its existence.