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Hurricane Juan was a large and erratic tropical cyclone that looped twice near the Louisiana coast, causing widespread flooding for several days. It was the tenth named storm of the 1985 Atlantic hurricane season, forming in the central Gulf of Mexico in late October. Juan moved northward after its formation, and was subtropical in nature with its large size. On October 27, the storm became a hurricane, reaching maximum sustained winds of 85 mph (140 km/h) just offshore southern Louisiana. Due to the influence of an upper-level low, Juan looped just offshore southern Louisiana before making landfall near Morgan City on October 29. Weakening to tropical storm status over land, Juan turned back to the southeast to open waters, crossing over the Mississippi River Delta. After turning to the northeast, the storm made its final landfall just west of Pensacola, Florida late on October 31. Juan continued quickly to the north and was absorbed by an approaching cold front, although its moisture contributed to a deadly flood event in the Mid-Atlantic states. Juan was the last of three hurricanes to move over Louisiana during the season, including Danny in August and Elena in early September. It formed quickly in the northern Gulf of Mexico, which prevented prompt evacuations of offshore oil rigs and advance warning. As a result, nine people died offshore Louisiana due to drowning in a boat or from an overturned oil rig. Onshore, the hurricane dropped torrential rainfall totaling in Galliano, Louisiana. The combination of the rains and a high storm surge flooded 50,000 houses and many towns in southern Louisiana, causing extensive agriculture damage. Damage in the state alone reached about $1 billion. Elsewhere, the flooding in Texas caused roads to close, while heavy rains damaged crops and houses in southern Mississippi and Louisiana. The outer rainbands of Juan spawned 15 tornadoes along the Florida panhandle that caused over $1 million damage. Overall, Juan caused about $1.5 billion in damage, making it among the costliest United States hurricanes, and there were 12 deaths. ==Meteorological history== The interaction between a tropical wave and a upper-level low moving southeastward from Texas spawned a broad trough over the central Gulf of Mexico on October 24. That day, there was a marked increase in convection, or thunderstorms. At the same time, the interaction between the trough and a ridge over the southeastern United States produced winds of near gale force along the northern Gulf of Mexico. Early on October 26, a tropical depression developed about 380 mi (610 km) south-southwest of New Orleans. Within 12 hours, the depression intensified into Tropical Storm Juan, based on satellite imagery and reports from the Hurricane Hunters. Initially, the structure was akin to a subtropical cyclone, with light winds near the center. Juan moved erratically at first, eventually tracking more steadily to the north-northeast on October 27.〔 After turning to the northwest late on October 27, Juan intensified into a hurricane, with maximum sustained winds of 75 mph (120 km/h), based on reports from the Hurricane Hunters.〔 Under the effects of a larger upper-level low, Juan slowed on October 28 while approaching the Louisiana coastline.〔 At 1200 UTC that day, the hurricane attained peak winds of 85 mph (140 km/h). After executing a loop just offshore southern Louisiana, Juan turned back to the east, making landfall at peak intensity near Morgan City at 1100 UTC on October 29.〔 Subsequently, Juan turned sharply to the northwest, executing another loop over southern Louisiana near Lafayette. Late on October 29, the hurricane weakened to tropical storm status, emerging into Vermilion Bay early the next day with winds of 65 mph (100 km/h). Juan turned to the east, moving along the southern Louisiana coast and re-organizing slightly.〔 On October 31, the storm moved across the Mississippi Delta near Burrwood, Louisiana and accelerated to the northeast,〔 influenced by an approaching upper-level trough. At 1200 UTC that day, Juan attained a secondary peak of 70 mph (110 km/h). In the subsequent six hours, the storm weakened slightly, making its final landfall just west of Pensacola, Florida with winds of 65 mph (100 km/h) late on October 31.〔 After striking Florida, Juan turned to the north and weakened over land. After moving through Alabama, the storm became extratropical over Tennessee on November 1. Although the Atlantic hurricane best track ceased tracking the circulation at 1800 UTC that day,〔 Juan continued generally northward through the Ohio Valley, and the center eventually crossed into Canada. The energy from Juan helped spawn an occluded low in the Tennessee Valley, which produced additional rainfall throughout the region.〔 An approaching cold front absorbed the remnants of Juan on November 3. 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 Juan (1985)」の詳細全文を読む スポンサード リンク
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