Hurricane Hanna (2008)

Hurricane Hanna was a moderately powerful but deadly tropical cyclone that caused extensive damage across the Western Atlantic, particularly in the Turks and Caicos Islands and the East Coast of the United States. The eighth named storm and fourth hurricane of the 2008 Atlantic hurricane season. It formed east-northeast of the northern Leeward Islands on August 28. Initially, the storm struggled to intensify due to moderate wind shear as it moved westwards towards the Bahamas. By August 31, Hanna had drifted southwards and began intensifying while over the Bahamas; it attained its peak intensity as a Category 1 hurricane while over the Turks and Caicos Islands. Due to the outflow of the nearby Hurricane Gustav, Hanna weakened back into a tropical storm the next day as it began to drift northwestwards towards the Southeastern United States. The storm struck Myrtle Beach, South Carolina, before moving up the Eastern Seaboard to become an extratropical cyclone as it moved by New England into Atlantic Canada early on September 7. The system raced across the North Atlantic, sweeping west of Great Britain on September 10 before turning north and becoming absorbed by a stronger extratropical cyclone between Iceland and Greenland late on September 12.

At least 537 deaths were reported (the final death toll will likely never be known), mostly due to flooding in the northern part of Haiti. Hanna also caused $160 million in damages to the U.S, but the exact damage in Haiti is unknown. Despite the high number of deaths caused by the hurricane, the name ''Hanna'' was not retired.

Meteorological history

On August 19, a tropical wave emerged off the coast of Africa and tracked westward across the Atlantic Ocean. After several days, an associated area of low pressure gained deep convection and organization. On August 28, while to the east-northeast of the northern Leeward Islands, the low formed into Tropical Depression Eight. Later that day, it attained tropical storm status, and as such was named ''Hanna'' by the National Hurricane Center. At the time, the low-level center of circulation was partially exposed on the western edge of the mass of convection, indicating westerly wind shear.

Tracking westward primarily under the steering current of a large ridge to the north, the convective pattern began to redevelop late on August 28. Since forecast, models predicted the storm would weaken and move southwestward due to outflow associated with nearby Hurricane Gustav. Despite this, the storm began entering a favorable environment, and was forecast to intensify. An upper-level low that had been producing wind shear moved away from the system, though light shear continued. At the same time, the low-level center once again became separated from the convection, which was primarily confined to a cyclonic banding feature in the eastern half of the circulation. It remained weak as it moved erratically westward while east of the Bahamas on August 30. Due to the influence of Hurricane Gustav's large circulation, Hanna suddenly took a sharp southerly turn and slowed down to drift while located to the north of the Turks and Caicos Islands. On September 1, as Hanna drifted to the south-southwest, convection increased and the storm began to intensify. Later that day around 1:30 pm EDT, an Air Force Reconnaissance Aircraft found winds within Hanna supportive of hurricane strength, and the National Hurricane Center upgraded Hanna to a hurricane. Early on September 2, strong wind shear in association with Hurricane Gustav began to affect Hanna and the storm was downgraded to a tropical storm on September 3. Hanna then sharply turned back northward, causing additional damage in Haiti. Over the course of the next three days, Hanna slighted northwestward towards the Bahamas, before turning abruptly north. By September 5, Hanna turned westward towards the Carolinas.
Early on September 6, 2008, Hanna made landfall near the South Carolina-North Carolina border. The system became an extratropical cyclone as it moved into Atlantic Canada early on September 7 and raced across the North Atlantic, sweeping west of Great Britain on September 10 before turning north and becoming absorbed by a stronger extratropical cyclone between Iceland and Greenland late on September 12.

Preparations

Greater Antilles

The National Hurricane Center and various governments issued multiple tropical cyclone warnings and watches due to the threat of Hanna. In southeastern Bahamas and the Turks and Caicos Islands, a tropical storm watch was posted at 15:00 UTC on August 30. Around 09:00 UTC the next day, the tropical storm watch was upgraded to a tropical storm warning in the Turks and Caicos Islands; six hours later, the watch was also increased in the southeastern Bahamas. Another tropical storm watch was issued for the central Bahamas at 15:00 UTC on August 31 and was upgraded to a tropical storm warning about six hours later. A hurricane watch was put into effect for the central Bahamas on September 1 at 15:00 UTC. Three hours later, all tropical storm warnings were upgraded to hurricane warnings, while the hurricane watch in the central Bahamas was discontinued.

Early on September 3, a hurricane watch was issued for the northwestern Bahamas and switched to a hurricane warning several hours later. That same day, the hurricane warning in effect for the central and southeastern Bahamas, as well as the Turks and Caicos Islands, was downgraded to a tropical storm warning. At 03:00 UTC on September 4, the hurricane warning for the northwestern Bahamas was also decreased to a tropical storm warning. About nine hours later, the tropical storm warning was cancelled for the southeastern Bahamas and the Turks and Caicos Islands. The remaining portion of the tropical storm warning, for the central and northwestern Bahamas, was discontinued late on September 5.

The Bahamas

In Turks and Caicos Islands, streets were cleared, while schools and airports were closed as Hanna approached. On Providenciales, 800 people stayed in shelters. The storm was predicted to bring up to of precipitation to the Turks and Caicos and southeastern Bahamas. In the Bahamas, National Emergency Operations Centre was used to provide advice to the public. All national medical facilities were inspected and equipped with necessary supplies and equipment. About 139 people and 20 others stayed in shelters on Acklins and Long Cay, respectively.

Hispaniola

Along the northern coast of Haiti, a tropical storm warning was issued from Môle-Saint-Nicolas to the border with Dominican Republic at 15:00 UTC on September 2. Six hours later, the warning area was extended to Port-au-Prince. Simultaneously, another tropical storm warning was issued along the north coast of Dominican Republic from Puerto Plata westward to Bahia de Manzanillo. By 03:00 UTC on September 4, the tropical storm warnings in both countries were discontinued.

United States and Canada

At 09:00 UTC on September 4, a tropical storm watch was issued from the mouth of the Altamaha River in Georgia to Edisto Beach, South Carolina. Simultaneously, a hurricane watch was posted from Edisto Beach to Surf City in North Carolina. The hurricane watch was extended further north to Ocracoke Inlet

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