Hurricane Sandy

The East Coast is cleaning up from Hurricane Sandy, which has so far have so far claimed 160 lives in America and Caribbean. I expect the death toll to rise, especially in the Northeast. Why was Hurricane Sandy so bad despite only being a Category 1 storm? I will look at Hurricane Sandy.

Hurricane Sandy formed from a tropical wave that moved out of Africa in early October. It entered the Caribbean on October 19 and was tagged as Invest 99L. The Caribbean for the 2012 season is largely not favorable due to wind shear from a weak El Nino that died (indications are that El Nino is returning). The lack of wind shear in the Caribbean and warm water made it favorable for development. The disturbance becomes Tropical Depression 18 and than Tropical Storm Sandy on October 22. Two days later, Sandy becomes a hurricane and heads north towards Jamaica. Sandy makes a direct landfall on Jamaica, near Kingston. Jamaica has not had a landfall since 1988 with Hurricane Gilbert. Than Sandy passes Jamaica and undergoes rapid intensification to 110 mph and makes landfall west of Santiago de Cuba. Satellite presentation suggests that Sandy was most likely a major hurricane and likely will be upgraded.

NAO during Hurricane Sandy.

Sandy heads towards the Bahamas and starts to “weaken”. Actually, Sandy is becoming more extratropical and getting larger. The wind shear has little effect on Sandy as it becomes larger and more intense as the pressure drops. The reason for this is that Sandy is influenced by a trough to the west and maintaining a warm core. Sandy also had the Gulf Stream, which allowed it to intensify further. One would think that Sandy would keep going to the northeast as most storms typically do especially in October due to jet stream. There was a strong high pressure around Greenland and the jet stream around it steered Sandy to the west towards the East Coast. A strong high pressure over Greenland is a negative North Atlantic Oscillation (NAO). Since that high pressure over Greenland blocked Sandy from going northeast and had no choice but to go westward. A negative NAO also generally means cooler and stormier winters as cold air from the north is pushed southwards.

Infrared image of Hurricane Sandy.

Sandy makes landfall 5 miles southwest of Atlantic City on the afternoon of October 30. By than Sandy is the largest hurricane on record for the Atlantic. It would be like if Super Typhoon Tip hit the East Coast, but not as intense. Most of the heavy rain was near the center, while the strongest winds and storm surge were to the northeast, which puts it over the New York City area. New York area did not get most of the rain from Sandy despite being on the “dirty” side of the storm. Instead they got the highest storm surge of nearly 14 feet at The Battery in Manhattan. The storm surge ravaged New York, Long Island, New Jersey, and Connecticut. It even ravaged areas north of New York along the Hudson River. Flooding was extensive in Lower Manhattan and Northern New Jersey. By the time Sandy passed, about 8 million people lost power, the second most after the 1993 Super Storm.

Let’s look at how Sandy stacks up.

Central Pressure: 945.5 Millibars
Sustained Winds At Landfall: 90 mph
Highest Rainfall: 12.55″ Easton, Maryland
Highest Snowfall: 36″ Richwood, West Virginia

Sandy is the most intense hurricane to hit north of Cape Hatteras. It beats the 1938 Long Island Express Hurricane, which ravaged the East Coast and claimed 600 lives. Sandy was a large rainmaker for areas east of Washington, DC. Not only Sandy dumped heavy rain, it dumped heavy snow in Appalachian Mountains. West Virginia got their first snow of the season in the form of a blizzard. Another interesting thing about Sandy is, it is one of the few hurricanes to make landfall on New Jersey from a westerly direction. Most storms that hit New Jersey are coming from the south, like Hurricane Irene did in 2011. The last storm to hit New Jersey like Sandy did was in 1903 and dubbed Vagabond Hurricane. The Vagabond Hurricane hit in September as a Category 1 hurricane and made landfall near Atlantic City.

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