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Hurricane Andrew was, at the time of its occurrence in August 1992, the most destructive hurricane in United States history. It caused major damage in the Bahamas and Louisiana, but the greatest impact was in South Florida, where it made landfall at Category 5 hurricane intensity on the Saffir–Simpson hurricane scale, with wind speeds up to 177 mph (285 km/h). Passing directly through the town of Homestead, Florida, a suburb south of Miami, Andrew obliterated entire blocks of homes, in many cases leaving only the concrete foundations. Over 25,000 houses were destroyed in Miami-Dade County alone, and nearly 100,000 more were severely damaged. The damage total across the affected regions exceeded $26 billion (1992 USD), and 65 people lost their lives in the hurricane. Andrew originated from a tropical wave over the central Atlantic, becoming the fourth tropical cyclone and the first hurricane of the 1992 Atlantic hurricane season. Initially, strong wind shear prevented much intensification, but after turning westward, Andrew entered a stage of rapid intensification; it peaked as a powerful Category 5 hurricane near the Bahamas on August 23. Though it briefly weakened to Category 4 strength while traversing the island nation, Andrew regained its Category 5 status before making two separate landfalls in South Florida—the first on Elliott Key and the second in Homestead. Several hours later, the hurricane emerged over the Gulf of Mexico at Category 4 strength, with the Gulf Coast of the United States in its projected path. After weakening slightly, Andrew moved ashore near Morgan City, Louisiana, as low-end Category 3 storm. The effects of land caused the small hurricane to rapidly lose its intensity, and it diminished to a depression by August 27 while crossing Mississippi. The next day, Andrew merged with a frontal system over the southern Appalachian Mountains. In the Bahamas, Andrew brought high tides, hurricane-force winds, and tornadoes, causing widespread structural damage, especially on Cat Cays. About 800 houses were destroyed in the archipelago, and there was substantial damage to the transport, water, sanitation, agriculture, and fishing sectors. Overall, Andrew left four dead and $250 million (1992 USD) in damage throughout the Bahamas. In parts of southern Florida, Andrew produced severe winds; a wind gust of 177 mph (282 km/h) was observed at a house in Perrine. These winds wreaked catastrophic damage in Florida—Miami-Dade County cities of Florida City, Homestead, and Cutler Ridge receiving the brunt of the storm. A total of 63,000 homes were destroyed and more than 101,000 others were damaged, leaving roughly 175,000 people homeless. As many as 1.4 million people lost power at the height of the storm. In the Everglades, 70,000 acres (280 km2) of trees were downed. Rainfall in Florida was substantial, peaking at 13.98 in (355 mm) in western Miami-Dade County. Altogether, Andrew killed 44 and left a record $25 billion in damage in the state. Before moving ashore Andrew caused extensive damage to oil platforms in the Gulf of Mexico, leading to $500 million in losses for oil companies. It produced hurricane-force winds along its path through Louisiana, leaving about 152,000 without electricity. Over 80% of trees in the Atchafalaya River Basin were downed, and the agriculture there was devastated. Throughout the basin and Bayou Lafourche, 187 million freshwater fish were killed in the hurricane. An F3 tornado in St. John the Baptist Parish wrecked 163 structures. With 23,000 houses damaged, 985 others destroyed, and 1,951 mobile homes demolished, property losses in Louisiana exceeded $1.5 billion. The hurricane caused the deaths of 17 people in the state, six of whom drowned offshore. Andrew spawned at least 28 tornadoes along the Gulf Coast, especially in Alabama, Georgia, and Mississippi. Throughout its path, Andrew left 65 dead and $26 billion in damage (1992 USD, $ USD); it is currently the fifth costliest hurricane in Atlantic hurricane history, behind only hurricanes Katrina and Wilma in 2005, Ike in 2008, and Sandy in 2012. Some sources put the damage from Andrew as high as $34 billion (1992 USD, $ USD).〔〔(【引用サイトリンク】publisher=Newsoxy )〕 ==Meteorological history== (詳細はtropical wave moved off the coast of Africa on August 14. Under the influence of a ridge of high pressure to its north, the wave tracked quickly westward. An area of convection developed along the wave axis to the south of the Cape Verde islands, and on August 15, meteorologists began classifying the system with the Dvorak technique. The thunderstorm activity became more concentrated, and narrow spiral rainbands developed around a developing center of circulation. Based on a Dvorak T-number of 2.0, it is estimated that Tropical Depression Three developed late on August 16, while about east-southeast of Barbados. Embedded within the deep easterlies, the depression tracked west-northwestward at . Initially, moderate wind shear prevented strengthening, until a decrease in shear allowed the depression to intensify into Tropical Storm Andrew at 1200 UTC on August 17.〔 By early August 18, the storm maintained concentrated convection near the center with spiral bands to its west as the winds increased to . Shortly thereafter the thunderstorms decreased markedly during the diurnal minimum and as the storm turned to the northwest, increased southwesterly wind shear from an upper-level low prevented Andrew from maintaining deep convection.〔 On August 19, a Hurricane Hunters flight into the storm failed to locate a well-defined center and on the following day, a flight found that the cyclone had degenerated to the extent that only a diffuse low-level circulation center remained; observations indicated the pressure rose to an unusually high . The flight indicated Andrew maintained a vigorous circulation aloft, with winds of recorded at flight level. Subsequently, the upper-level low weakened and split into a trough, which decreased the wind shear over the storm. Simultaneously, a strong high pressure cell developed over the southeastern United States, which built eastward and caused Andrew to turn to the west.〔 Convection became more organized as upper-level outflow became better established. An eye formed, and Andrew attained hurricane status early on August 22, while located about east-southeast of Nassau, Bahamas.〔 Six hours after becoming a hurricane, Andrew was predicted to make landfall near Jupiter, Florida with winds of . The hurricane accelerated as it tracked due westward into an area of very favorable conditions, and began to rapidly intensify late on August 22; in a 24‑hour period the atmospheric pressure dropped by to a minimum of .〔 On August 23, the storm attained Category 5 status on the Saffir–Simpson hurricane scale, and at 1800 UTC, Andrew reached peak winds of 175 mph (280 km/h) while located a short distance off Eleuthera island in the Bahamas. Operationally, the National Hurricane Center assessed its peak intensity as , which was upgraded to in a post-analysis after the season ended; the hurricane was later re-classified as a Category 5 hurricane.〔 Even with winds of 175 mph (280 km/h), Andrew was a small tropical cyclone, with winds of extending out only about from its center. After reaching that intensity, the hurricane underwent an eyewall replacement cycle. At 2100 UTC on August 23, Andrew made landfall on Eleuthera with winds of .〔 The cyclone weakened further while crossing the Bahama Banks, and at 0100 UTC on August 24, Andrew hit the southern Berry Islands of the Bahamas with winds of .〔 As it crossed over the warm waters of the Gulf Stream, the hurricane rapidly re-intensified as the eye decreased in size and its eyewall convection deepened.〔 At 0840 UTC on August 24, Andrew struck Elliott Key with winds of and a pressure of . About 25 minutes after its first Florida landfall, Andrew hit just northeast of Homestead with a slightly lower pressure of .〔 As the eye moved onshore in Florida, the convection in the eyewall strengthened due to increased convergence, and Hurricane Hunters reported a warmer eyewall temperature than two hours prior. However, Andrew weakened as it continued further inland, and after crossing southern Florida in four hours, the storm emerged into the Gulf of Mexico with winds of .〔 In the Gulf of Mexico, the eye remained well-defined as the hurricane turned to the west-northwest, a change due to the weakening of the ridge to its north. Andrew steadily re-intensified over the Gulf of Mexico, reaching winds of late on August 25.〔 As the high pressure system to its north weakened, a strong mid-latitude trough approached the area from the northwest. This caused the hurricane to decelerate to the northwest, and winds decreased as Andrew approached the Gulf Coast of the United States.〔 At 0830 UTC on August 26, the cyclone made its final landfall in a sparsely populated area of Louisiana about west-southwest of Morgan City with winds of .〔 Hurricane Andrew weakened rapidly as it turned to the north and northeast, falling to tropical storm intensity within ten hours. After entering Mississippi, the cyclone deteriorated to tropical depression status early on August 27. Accelerating northeastward, the depression began merging with the approaching frontal system, and by midday on August 28, Andrew ceased to meet the qualifications of a tropical cyclone while located over the southern Appalachian Mountains.〔 The remnants continued moving towards northeast and lost its identity on August 28, while merging with the remnants of Hurricane Lester within the frontal zone over the Mid-Atlantic states. 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 Andrew」の詳細全文を読む スポンサード リンク
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