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Tropical Storm Lee was the twelfth named storm and thirteenth system overall of the 2011 Atlantic hurricane season, developing from a broad tropical disturbance over the Gulf on September 1. It was designated as Tropical Storm Lee the next day. Due to the large size, as well as the slow forward movement of the storm, heavy rainfall occurred in southern Louisiana, Mississippi, Alabama, and the Florida panhandle. Flooding associated with the rains caused significant property damage in the areas, with drowning deaths reported in both Mississippi and Georgia. 〔(【引用サイトリンク】url=http://www.cnn.com/2011/US/09/07/weather.lee/ )〕 Elsewhere, the storm helped spread wildfires that destroyed homes and killed two people in Texas, and a traffic accident in Alabama resulted in one death. Rough surf offshore drowned one person in each of these states. Lee spawned 30 confirmed tornadoes in the United States. Lee was the first subtropical or tropical storm to make landfall in Louisiana since Hurricane Gustav in 2008. Heavy rainfall resulted in historic flooding in Pennsylvania, New York, and elsewhere. Damage total is estimated to be around $1.6 billion. ==Meteorological history== In late August 2011, much of the western Caribbean came under the influence of abundant tropical moisture. Combined with favorable upper diffluence, the moisture allowed for a perpetual area of disturbed weather to form; this in return contributed to the genesis of a weak tropical wave, or an elongated low-pressure feature at the lower levels of the atmosphere. The wave initiated a more or less westward, then west-northwestward drift across the Yucatán Peninsula toward the Gulf of Mexico, although it remained largely disorganized while doing so. After arriving in the gulf on August 31, the system failed to develop much under initially high wind shear; however, the National Hurricane Center (NHC) forecast some potential for the formation of a tropical cyclone in a day or two. Strong convection increased mainly to its east during the next day, and by 2300 UTC data from a reconnaissance aircraft confirmed the presence of a closed circulation center. At this point, the system was considered sufficiently organized to be upgraded to a tropical depression, with its center located 255 mi (360 km) to the southwest of the mouth of the Mississippi River. Situated within an area of weak steering currents, the depression remained nearly stationary during the initial stages of its existence. It exhibited a poor organization at the time; the circulation remained elongated, with a broad center of light winds removed from the sheared convective mass.〔 Over the course of September 2 the convection began to deepen over its eastern portion, which later translated into an increase in the winds. Based on this, the depression was upgraded to Tropical Storm Lee at 1800 UTC. Lee meandered erratically north-northwestward to northward for the rest of the day, and with a small upper low advecting dry air into the circulation any deep convection over its western semicircle remained scarce during that time. By September 3, the storm sustained a large radius of maximum winds within the still elongated circulation; this unusual structure to purely tropical cyclones, combined with an overall hybrid appearance on satellite images, suggested Lee transitioned into a subtropical storm as it approached the Louisiana coast, similar to the transition of Tropical Storm Allison in 2001. Stalling off the coast of Louisiana, the storm's windfield continued to expand and increase in strength, though two separate low-level centers became evident within the exceedingly large circulation later that day. Due to a large portion of circulation remaining over the warm waters of the Gulf of Mexico, Lee weakened more slowly than a typical tropical cyclone would as it moves inland. Lee finally moved inland over south-central Louisiana on the morning of September 4 as a subtropical storm with winds of 45 mph (75 km/h). By that evening, Lee had weakened to a tropical depression in operational estimates, due to land interaction and continental air being advected into the system. Lee had begun to interact with a strong upper-level trough in the Mississippi Valley as it continued to move off to the east-northeast. It was designated an extratropical low adjacent to the trough on the morning of September 5, while maintaining tropical storm-force winds according to post-analysis. The extratropical remnant weakened further on September 6, as it entered northwestern Georgia. Early on September 7, at 0000 UTC, the remnant of Lee dissipated.〔 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「Tropical Storm Lee (2011)」の詳細全文を読む スポンサード リンク
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