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Hurricane Danny was the only hurricane to make landfall in the United States during the 1997 Atlantic hurricane season, and the second hurricane and fourth tropical storm of the season. The system became the earliest-formed fifth tropical or subtropical storm of the Atlantic season in history when it attained tropical storm strength on July 17, and held that record until the 2005 Atlantic hurricane season when Tropical Storm Emily broke that record by several days. Like the previous four tropical or subtropical cyclones of the season, Danny had a non-tropical origin, after a trough spawned convection that entered the warm waters of the Gulf of Mexico. Danny was guided northeast through the Gulf of Mexico by two high pressure areas, a rare occurrence in the middle of July. After making landfall on the Gulf Coast, Danny tracked across the southeastern United States and ultimately affected parts of New England with rain and wind. Danny is notable for its extreme rainfall, the tornadoes generated by it, and the destruction it produced on its path, causing a total of nine fatalities and $ (1997 USD, $ USD) in damage. The storm dropped a record amount of rainfall for Alabama, as at least 36.71 inches (932 mm) fell on Dauphin Island. Flooding, power outages, and erosion occurred in many areas of the Gulf Coast, and rescues had to be executed from flooded roadways. Tornadoes generated by Danny on the East Coast caused a great amount of damage. Of the nine fatalities caused by Danny, one happened off the coast of Alabama, four occurred in Georgia, two occurred in South Carolina, and two occurred in North Carolina. == Meteorological history == A broad mid-tropospheric trough over the southeastern United States spawned an area of convection over the lower Mississippi River Valley on July 13, and drifted southward towards the warm waters of the Gulf of Mexico. As it moved into the Gulf of Mexico, a weak and isolated surface low pressure area formed off the coast of Louisiana. The circulation in the system steadily expanded, and initially the surface winds and convection were intermittent. On July 16, deep convection increased and organized near the center, and oil rigs and surface buoys reported surface winds of 30 mph (50 km/h). Based on the observations, it is estimated the system developed into Tropical Depression Four on July 16 while about 150 miles (240 km) south of the southwestern Louisiana coastline. The depression slowly organized for the next day, as it drifted to the northeast. On July 17, the rate of organization and development of deep convection increased considerably, and the depression strengthened into Tropical Storm Danny later that day. From the night of July 17 through July 18, Danny quickly developed deep convection and banding features in the favorable environment of the Gulf of Mexico, and reached hurricane status later on July 18. Located between two high pressure systems, Danny continued its unusual July track to the northeast, and crossed over southeastern Louisiana near the Mississippi River Delta. A small storm, Danny continued to strengthen after reaching the coastal waters off Mississippi on the night of July 18, and attained a peak of 80 mph (130 km/h) early on July 19. The hurricane force winds, however, were confined to the eyewall. After stalling near the mouth of Mobile Bay on July 19, Hurricane Danny turned to the east, and made its final landfall near Mullet Point, Alabama later that day.〔 The storm rapidly weakened as it continued northward, and degenerated into a tropical depression by July 20. The weak depression moved through Alabama, Georgia, South Carolina, and North Carolina, maintaining a well-defined cloud signature.〔 Due to a front behind the system, Danny unusually strengthened to a tropical storm over North Carolina on July 24. This rare phenomenon occurred due to interaction with a developing trough and its associated baroclinic zone.〔 Danny entered the Atlantic Ocean, north of the North Carolina-Virginia border, near Virginia Beach. It quickly reached a secondary peak of , and continued rapidly northeastward towards the waters of the Atlantic. A strong mid to upper-level cyclone turned Danny northward, threatening Massachusetts. It stalled while just southeast of Nantucket on July 26, turned to the east out to sea, and became extratropical later that day. On July 27, the former hurricane merged with a frontal zone.〔 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 Danny (1997)」の詳細全文を読む スポンサード リンク
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