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Hurricane Allen was a rare and extremely powerful Cape Verde-type hurricane which struck the Caribbean, eastern and northern Mexico then southern Texas. It was the first and strongest hurricane of the 1980 Atlantic hurricane season. The first named storm and first tropical cyclone of the 1980 Atlantic hurricane season, it was one of the strongest hurricanes in recorded history and one of the few hurricanes to reach Category 5 status on the Saffir–Simpson Hurricane Scale on three separate occasions, and spent more time as a Category 5 than any other Atlantic hurricane. Allen is the only hurricane in the recorded history of the Atlantic basin to achieve sustained winds of 190 mph (305 km/h),〔All wind speeds in the article are maximum sustained winds sustained for one minute, unless otherwise noted.〕 thus making it the strongest Atlantic hurricane by wind speed. Until Hurricane Patricia in 2015, this was also the highest sustained winds in the entire Western Hemisphere. Throughout its life, Allen moved through the deep tropics on a west-northwesterly course through the tropical Atlantic Ocean, Caribbean Sea, and Gulf of Mexico before making its final landfall near the United States–Mexico border. At peak strength, it passed near Haiti, causing hundreds of deaths and heavy damage. After crossing the Gulf of Mexico, Allen weakened as it struck the lower Texas coast, causing high winds, a significant storm surge, and heavy rainfall, which caused damage to southern Texas. Overall, Allen killed 290 people and left just over in damage (1980 USD), mostly within the United States and Haiti. Due to its impact, the name Allen was retired from the six-year revolving list of Atlantic tropical cyclone names in 1981 and the name was replaced by Andrew. The name Andrew was subsequently retired after the 1992 season's Hurricane Andrew. The dissipating storm precipitated the end of the Heat Wave of 1980 in places like Dallas/Fort Worth, Texas, which had recorded 69 days of heat. ==Meteorological history== Allen was an early Cape Verde-type hurricane which originated from a tropical wave that previously moved off the African coastline on July 30. The system developed as it moved westward, becoming a tropical depression on August 1.〔 However, the National Hurricane Center did not initiate advisories on Allen until almost 24 hours later, while centered east of the Windward Islands. Early on August 2, as the depression moved towards the Caribbean, it had intensified, and became the first named storm of the season. The National Hurricane Center noted that conditions appeared favorable for further intensification. However, it was also noted that a large cold-low north of Puerto Rico was producing strong westerly wind shear, which would cause Allen to possibly encounter unfavorable conditions within 72 hours. Although slower forward movement was anticipated, Allen kept at generally the same westward pace between .〔 By August 3, the National Hurricane Center retracted predictions of less favorable conditions from the cold-low north of Puerto Rico, since that weather system was weakening and moving westward. At 1600 UTC on August 3, the National Hurricane Center upgraded Allen to hurricane status, as an Air Force Plane recorded winds of 100 mph (155 km/h). However, in post-analysis, it was discovered that Allen had been a hurricane since 0000 UTC on August 3. Shortly after the upgrade, Allen began a period of rapid deepening, and intensified into a major hurricane at 0000 UTC August 4, while roughly northwest of Bridgetown, Barbados. Six hours later, Allen passed only south of St. Lucia at 0600 UTC.〔 Although the National Hurricane Center noted that conditions favored slow strengthening, Allen continued to rapidly intensify, and became a Category 4 hurricane only two hours after that advisory.〔 Later on August 4, the National Hurricane Center noted a barometric pressure of , and that the it would not drop significantly within 24 hours. Shortly before 0000 UTC on August 5, the minimum pressure decreased to , which was noted as equivalent to Hurricane David in the previous season. By August 5, Allen intensified into a Category 5 hurricane during while south of Puerto Rico. This made Allen the earliest Category 5 hurricane in the Atlantic on record,〔 but was later surpassed by Hurricane Emily which reached that intensity on July 16, 2005. During this time, Allen attained a central pressure of , the lowest pressure on record in the eastern Caribbean sea. Hence, the barometric pressure dropped by less than 10 hours after the National Hurricane Center stated that the pressure would not decrease significantly within 24 hours. The eye passed between Hispaniola and Jamaica as a Category 4 hurricane. After weakening due to friction with the mountains of Haiti and Jamaica, Allen intensified back to a Category 5 hurricane, retaining this intensity for over a day. It then moved past the islands of Cayman Brac and Little Cayman causing moderate damage on Cayman Brac with winds near 135 mph. The storm then moved between Cuba and the Yucatán Peninsula, reaching its minimum pressure of while crossing the Yucatán Channel. During Allen's trek through the Caribbean Sea and the Gulf of Mexico, its center of circulation never crossed over land despite its close passage to various islands in and around the Caribbean sea.〔 Allen again weakened to a Category 4 storm due to friction with Mexico, but restrengthened into a Category 5 hurricane for a third time as it moved over the open waters of the Gulf of Mexico, keeping this intensity for nearly a full day and with a pressure drop to , the lowest pressure ever recorded in the western Gulf of Mexico. Shortly before landfall, a dry air mass in the western Gulf of Mexico caused the storm to weaken substantially. Allen made landfall north of Brownsville, Texas as a Category 3 storm with maximum sustained winds of 115 mph (185 km/h). Allen became extratropical on August 11.〔 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 Allen」の詳細全文を読む スポンサード リンク
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