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Hurricane Agnes was, at the time, the costliest hurricane to hit the United States in recorded history. The second tropical cyclone and first named storm of the 1972 Atlantic hurricane season, Agnes developed on June 14 from the interaction of a polar front and an upper trough over the Yucatán Peninsula. Initially forming as a tropical depression, the storm headed slowly eastward and emerged into the western Caribbean Sea on June 15. Once in the Caribbean, the depression began to strengthen, and by the following day, it became Tropical Storm Agnes. Thereafter, Agnes slowly curved northward and passed just west of Cuba on June 17. Early on June 18, the storm intensified enough to be upgraded to Hurricane Agnes. Heading northward, the hurricane eventually made landfall near Panama City, Florida late on June 19. After moving inland, Agnes rapidly weakened and was only a tropical depression when it entered Georgia. The weakening trend halted as the storm crossed over Georgia and into South Carolina. While over eastern North Carolina, Agnes re-strengthened into a tropical storm on June 21, as a result of baroclinic activity. Early the following day, the storm emerged into the Atlantic Ocean before re-curving northwestward and making landfall near New York City as a strong tropical storm. Agnes quickly became an extratropical cyclone on June 23, and tracked to the northwest of Great Britain before becoming absorbed by another cyclone on July 6. Though it moved slowly across the Yucatán Peninsula, damage in Mexico is unknown. Although the storm bypassed the tip of Cuba, heavy rainfall occurred, killing seven people. In Florida, Agnes caused a significant tornado outbreak, with at least 26 confirmed twisters, two of which were spawned in Georgia. The tornadoes and two initially unconfirmed tornadoes in Florida alone resulted in over $4.5 million (1972 USD) in damage and six fatalities. At least 2,082 structures in Florida suffered either major damage or were destroyed. About 1,355 other dwellings experienced minor losses. Though Agnes made landfall as a hurricane, no hurricane force winds were reported. Along the coast abnormally high tides resulted in extensive damage, especially between Apalachicola and Cedar Key. Light to moderate rainfall was reported in Florida, though no significant flooding occurred. In Georgia, damage was limited to two tornadoes, which caused approximately $275,000 in losses. Minimal effects were also recorded in Alabama, Connecticut, Delaware, Rhode Island, South Carolina, and Tennessee; though one fatality was reported in Delaware. The most significant effects, by far, occurred in Pennsylvania, mostly due to severe flooding. The hurricane severely flooded the Susquehanna River and the Lackawanna River causing major damage to the Scranton/Wilkes-Barre metropolitan area. In both Pennsylvania and New Jersey combined, about 43,594 structures were either destroyed or significantly damaged. In Canada, a mobile home was toppled, killing two people. Overall, Agnes caused 128 fatalities and nearly $3 billion in damage, though more recently, it is estimated that there were $2.1 billion in losses associated with the storm. Due to the significant effects, the name ''Agnes'' was retired in the spring of 1973. ==Meteorological history== In early-mid June 1972, atmospheric conditions favored tropical cyclogenesis in the Caribbean Sea. Banded convection developed in the northwestern Caribbean Sea by June 11, though the system did not significantly organize. After an upper trough moved east, wind shear decreased, causing lower atmospheric pressures observations in Cozumel, Quintana Roo, Mexico. It is estimated that a tropical depression developed by 1200 UTC on June 14, while centered over the Yucatán Peninsula, about southeast of Mérida, Yucatán. The depression tracked eastward and entered the western Caribbean Sea on June 15.〔 Operationally, the National Hurricane Center did not initiate advisories on the depression until 1500 UTC on June 15. Early on June 16 at 0000 UTC, the depression strengthened into Tropical Storm Agnes.〔 However, the depression was not operationally upgraded until sixteen hours later. After becoming a tropical storm on June 16, Agnes slowly curved northward and approached the Yucatán Channel.〔 Late on June 17, it was noted that projected path indicated the possibly of landfall in western Cuba. However, the storm remained offshore, though it closely brushed the western tip of Cuba. At 1200 UTC on June 18, Agnes intensified into a hurricane while in the southeastern Gulf of Mexico.〔 Prematurely, the National Hurricane Center operationally upgraded Agnes to a hurricane at 0200 UTC on that day. Upon becoming a hurricane, Agnes attained its maximum sustained winds of 85 mph (140 km/h), though it had not reached its minimum atmospheric pressure. Due to unfavorable conditions, Agnes leveled-off slightly in intensity and weakened to a minimal hurricane while approaching the Gulf Coast of the United States.〔 Shortly before 2200 UTC on June 19, Agnes made landfall near Cape San Blas, Florida with winds of 75 mph (120 km/h). At 0000 UTC on June 20, only a few hours after moving inland, Agnes weakened to a tropical storm. After crossing the Florida/Alabama/Georgia stateline, Agnes rapidly weakened to a tropical depression. While over Georgia, the depression curved northeastward and eventually to the east-northeast after entering South Carolina.〔 Though the storm had not dissipated, the National Hurricane Center issued its final bulletin on Agnes at 1600 UTC on June 20. By early on June 21, a large extratropical trough spawned a low pressure area, which resulted in baroclinic activity. As a result, Agnes restrengthened into a tropical storm at 1800 UTC on June 21, while centered over eastern North Carolina.〔 Three hours later, the National Hurricane Center noted decreasing atmospheric pressures, and indicated that winds had reached gale force winds and once again upgraded Agnes to a tropical storm. By early on June 22, Agnes emerged into the northwestern Atlantic Ocean, where it continued to re-intensify. At 1200 UTC, Agnes reached its minimum atmospheric pressure of , as reported by a reconnaissance aircraft. However, maximum sustained winds were at only 70 mph (110 km/h).〔〔 Late on June 22, Agnes made its final landfall on Long Island, New York, near New York City with winds of 65 mph (100 km/h). Agnes began its long life as an extratropical cyclone once cold air invaded its circulation late on June 22. The system looped across south-central Pennsylvania on June 23 and then looped across southern Ontario on June 25. It spawned a tornado in Maniwaki, Ontario early that day, which killed two and injured 11 people. The cyclone sped east-northeast, reaching Cape Breton on June 27 before intensifying as it re-entered the North Atlantic. After moving as far north as the 61st parallel while crossing the 25th meridian west on the morning of June 29, Agnes turned southeastward. Its central pressure bottomed out near towards 0000 UTC on June 30. Between July 1 and July 3, the long-lived system looped between Ireland and Iceland while weakening once more. The system turned northeast, strengthening one more time while accelerating across the Hebrides on July 4 through 5. A stronger system moving in from the west finally absorbed Agnes on July 6 while finally located to the southeast of Iceland. 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 Agnes」の詳細全文を読む スポンサード リンク
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