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Hurricane Floyd was a very powerful Cape Verde-type hurricane which struck the east coast of the United States. It was the sixth named storm, fourth hurricane, and third major hurricane in the 1999 Atlantic hurricane season. Floyd triggered the third largest evacuation in US history (behind Hurricane Gustav and Hurricane Rita, respectively) when 2.6 million coastal residents of five states were ordered from their homes as it approached. The Cape Verde-type hurricane formed off the coast of Africa and lasted from September 7 to September 19, peaking in strength as a very strong Category 4 hurricane—just 2 mph short of the highest possible rating on the Saffir–Simpson Hurricane Scale. It was among the largest Atlantic hurricanes of its strength ever recorded. Floyd was once forecast to strike Florida, but turned away. Instead, Floyd struck The Bahamas at peak strength, causing heavy damage. It then paralleled the East Coast of the United States, causing massive evacuations and costly preparations from Florida through the Mid-Atlantic states. The storm weakened significantly, however, before striking the Cape Fear region, North Carolina as a very strong Category 2 hurricane, and caused further damage as it traveled up the Mid-Atlantic region and into New England. The hurricane produced torrential rainfall in Eastern North Carolina, adding more rain to an area hit by Hurricane Dennis just weeks earlier. The rains caused widespread flooding over a period of several weeks; nearly every river basin in the eastern part of the state exceeded 500-year flood levels. In total, Floyd was responsible for 57 fatalities and $6.9 billion (1999 USD; $ USD) in damage. Due to the destruction, the World Meteorological Organization retired the name ''Floyd''. ==Meteorological history== Floyd originated as a tropical wave that exited the coast of Africa on September 2. It moved steadily westward and remained disorganized and devoid of deep convection until September 7, when a curved band of deep convection developed over the center in response to a developing anticyclone. At this point, the National Hurricane Center designated it as Tropical Depression Eight, while it was approximately east of the Lesser Antilles. A strong ridge of high pressure to its north forced the developing tropical cyclone westward over warmer waters, allowing it to strengthen to Tropical Storm Floyd on September 8. Although a large storm, Floyd initially lacked a well-defined inner core, resulting in slow strengthening and preventing rapid intensification. On September 10 it organized enough to reach hurricane status, and Floyd approached major hurricane strength on September 11 while north of the Leeward Islands. The central Atlantic upper tropospheric trough, along with an upper-level low in the eastern Caribbean Sea, produced vertical wind shear over the hurricane and caused its winds to weaken to . A turn to the west, caused by building of high pressures, was followed by a period of rapid intensification: in 24 hours maximum sustained winds increased from ,〔All wind speeds in the article are maximum sustained winds sustained for one minute, unless otherwise noted.〕 while the pressure dropped to by morning on September 13, the third lowest pressure for a hurricane ''not'' to reach Category 5 intensity in the Atlantic Ocean—only Hurricane Opal and Hurricane Gloria had lower pressures than Floyd. One contributor to the intensification was the high oceanic heat content along the storm's path.〔 Hurricane Floyd remained just below Category 5 status on the Saffir–Simpson Hurricane Scale for 12 hours while crossing The Bahamas, making landfalls on Eleuthera and Abaco islands,〔 before an eyewall replacement cycle weakened it to a Category 3 hurricane with winds of . The new, larger eyewall contracted slightly, and the hurricane briefly re-intensified to Category 4 status. A strong mid- to upper-level trough eroded the western portion of the high-pressure ridge, steering Floyd to the northwest. It paralleled the eastern Florida coast off shore, and steadily weakened because of entrainment of dry air and upper-level shear.〔 The storm remained extremely large, however; at its peak, tropical storm-force winds spanned a diameter of , making Floyd one of the largest Atlantic hurricanes of its intensity ever recorded. Floyd accelerated to the north and northeast, and weakened greatly to a Category 2 hurricane. It made landfall in Cape Fear, North Carolina with winds of on September 16. After crossing over North Carolina and southeastern Virginia, it briefly re-entered the western Atlantic Ocean before reaching Long Island on September 17. The storm gradually lost its tropical characteristics due to an approaching frontal zone and became extratropical over southern Maine late on September 17. The extratropical storm continued to the northeast, and after passing over the Canadian Maritimes, it was absorbed by a cold front to the east of Newfoundland.〔 == Preparations == Although Floyd's track prediction was above average while out at sea, the forecasts as it approached the coastline were merely average compared to forecasts from the previous ten years. The official forecasts did not predict Floyd's northward track nor its significant weakening before landfall. Nearly all of the East Coast, from Florida City, Florida, to Plymouth, Massachusetts, was under a Hurricane Warning at some point; however, only a fraction of this area actually received hurricane-force winds. The last time such widespread hurricane warnings occurred was during Hurricane Donna in 1960, although the warnings for that storm were accurate.〔 Initial fears were of a direct hit as a large Category 4 hurricane in Florida, potentially costlier and deadlier than Hurricane Andrew had been in 1992. In preparation for a potentially catastrophic landfall, more than one million Florida residents were told to evacuate, of which 272,000 were in Miami-Dade County.〔 〕 U.S. President Bill Clinton declared a federal state of emergency in both Florida and Georgia in anticipation of the storm's approach. As the storm turned to the north, more people were evacuated as a progressively larger area was threatened. The massive storm caused what was at the time the largest peacetime evacuation ever in the U.S., with around 2.6 million evacuating coastal areas in Florida, Georgia, and the Carolinas. With the storm predicted to hit near Cape Canaveral with winds of over , all but 80 of Kennedy Space Center's 12,500-person workforce were evacuated. The hangars that house three space shuttles can withstand winds of only , and a direct hit could have resulted in potentially billions of dollars in damage of space equipment, draining funds of an already money-strained government organization. In the theoretical scenario, the damage would be caused by water, always a potential problem in an area only nine feet above sea level. If water entered the facility, it would damage the electronics as well as requiring a complete inspection of all hardware. When Floyd actually passed by the area, Kennedy Space Center only reported light winds with minor water intrusion. Damage was minor overall, and was repaired easily. A hurricane warning was issued for the North Carolina coastline 27 hours prior to landfall. However, due to the size of the storm, initial forecasts predicted nearly all of the state would be affected in one form or another. School systems and businesses as far west as Asheville shut down for the day landfall was predicted, but, as it turned out, only the Coastal Plain sustained significant damage; much of the state west of Raleigh escaped unscathed. In New York City, public schools were closed on September 16, 1999, the day Floyd hit the area. This was a rare decision by the city, as New York City public schools close on average once every few years. Before Floyd, the last time New York City closed its schools was for the Blizzard of 1996. After Floyd, the next time its public schools would close was due to a blizzard on March 5, 2001.〔(【引用サイトリンク】title=Breaking, World, US & Local News - nydailynews.com - NY Daily News ) 〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hurricane Floyd」の詳細全文を読む スポンサード リンク
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