In the days leading up to the arrival of Hurricane Sandy, storm surge was identified as one of the greatest risks for people living in coastal communities such as Martha’s Vineyard.
Storm surge is an abnormal rise of water generated by a storm, over and above the predicted astronomical tides, according to the National Hurricane Center. Storm surge should not be confused with storm tide, which is defined as the water level rise due to the combination of storm surge and the astronomical tide. This rise in water level can cause extreme flooding in coastal areas particularly when storm surge coincides with normal high tide, resulting in storm tides reaching up to 20 feet or more in some cases.
Dukes County has experienced eight hurricanes between 1900 and 2010, according to a NHS chart. The worst occurred in 1938.
The Long Island Express, the New England Hurricane of 1938, was a fast-moving Category 3 hurricane that struck Long Island and New England with little warning on September 21. A storm surge of 10 to 12 feet inundated the coasts of Rhode Island, Connecticut, southeastern Massachusetts, and Long Island, NY, especially in Narragansett Bay and Buzzards Bay. Six hundred people died due to the storm.
The “Long Island Express” was first detected over the tropical Atlantic on September 13, although it may have formed a few days earlier. Moving generally west-northwestward, it passed to the north of Puerto Rico on the 18th and 19th, likely as a category 5 hurricane. It turned northward on September 20 and by the morning of the 21st it was 100 to 150 miles east of Cape Hatteras, North Carolina. At that point, the hurricane accelerated to a forward motion of 60 to 70 mph, making landfall over Long Island and Connecticut that afternoon as a Category 3 hurricane.
Blue Hill Observatory measured sustained winds of 121 mph with gusts to 183 mph (likely influenced by terrain).