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Tropical Storm Emilia was a rare tropical cyclone that affected the Baja California peninsula in July 2006. The sixth tropical depression and fifth tropical storm of the 2006 Pacific hurricane season, it developed on July 21 about 400 miles (650 km) off the coast of Mexico. It moved northward toward the coast, reaching peak winds of 65 mph (105 km/h) before turning westward and encountering unfavorable conditions. Emilia later turned to the north, passing near Baja California as a strong tropical storm. Subsequently the storm moved further away from the coast, and on July 27 it dissipated. The storm brought tropical storm force winds and precipitation to the southwestern Mexican coastline. Later, Emilia produced similar conditions in the southern portion of the Baja California peninsula, where its passage caused minor damage and flooding. Moisture from Emilia reached the southwestern United States, producing thunderstorms and flash flooding in Arizona, as well as beneficial rainfall in southern California. No deaths were reported in association with Emilia. ==Meteorological history== The origins of Emilia can be traced to a tropical wave that crossed northern Central America into the eastern Pacific Ocean on July 16. The system moved westward, developing a well-defined low pressure area about 525 miles (850 km) southwest of Acapulco by July 19. The next day, its forward motion had shifted to a slow north-northwest track, and with its convection continuing to organize around the low, the National Hurricane Center (NHC) remarked on the potential for tropical cyclogenesis. Early on July 21, its thunderstorm activity organized enough for the NHC to classify it as Tropical Depression Six-E, located to the southwest of Acapulco.〔 Upon becoming a tropical cyclone, the depression existed in an area of weak steering currents,〔 though a general motion to the north-northwest was influenced by a large subtropical ridge over the southwest United States.〔 The circulation was initially located east of the main convection, due to the presence of wind shear. Convection increased near the center despite the shear, and on July 22 the depression attained tropical storm status about 400 mi (650 km) south of Manzanillo, Colima; it was named ''Emilia'' by the NHC. Around the same time, the storm was developing better-defined rainbands,〔 and with favorable conditions expected, Emilia was forecast to attain hurricane status; the NHC noted the potential for rapid deepening as the storm passed near southwestern Mexico. Early on July 23, the storm briefly became disorganized, with the low-level circulation becoming ill-defined. Around the same time, Emilia passed about 175 mi (280 km) southwest of Manzanillo, which was its closest approach to southwestern Mexico; it is believed to have caused tropical storm force wind gusts along the coastline.〔 Later that day, after turning west-northwestward, the convection increased markedly as an eyewall began to form. Operationally, it was estimated to have reached winds of 70 mph (115 km/h), and it was forecast to continue strengthening to attain Category 2 status on the Saffir-Simpson scale. However, the NHC later re-assessed Emilia as reaching peak winds of 65 mph (105 km/h), since the eye feature was temporary and not well-defined.〔 Shortly after reaching peak intensity, a sharp increase in wind shear caused Emilia to weaken quickly to winds of 50 mph (85 km/h).〔 Operationally, the NHC initially continued to assess the storm as with winds of 70 mph (115 m/h), with hurricane status predicted. However, the decrease in strength became evident on July 24, when dry air became entrained in the circulation; at the same time, the convection became limited to the southern semicircle of the storm. On July 25, the wind shear decreased as the storm turned toward the Baja California peninsula,〔 despite that tropical cyclones affecting the Baja California peninsula in the month of July are rare. Convection increased in coverage,〔 and an eye feature re-appeared early on July 26 as it again attained peak winds of 65 mph (105 km/h).〔 Emilia maintained peak winds for about 18 hours, during which it passed about 60 mi (95 km) southwest of Cabo San Lazaro, which is a cape located southwest of Ciudad Constitución on the southwestern coast of the Baja California peninsula. After brushing the peninsula with its outer rainbands, Emilia turned away from the coast into cooler waters, and subsequently began to weaken rapidly. On July 27 it deteriorated into a tropical depression, and the next day Emilia degenerated into a convective-less remnant low. The low continued westward until turning northward on July 30, and on July 31 the remnants of Emilia dissipated about 495 mi (800 km) west-southwest of San Diego, California.〔 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 Emilia (2006)」の詳細全文を読む スポンサード リンク
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