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Tropical Storm Etau was the deadliest tropical cyclone to impact Japan since Typhoon Tokage in 2004. Forming on August 8, 2009 from an area of low pressure, the system gradually intensified into a tropical storm. Tracking in a curved path around the edge of a subtropical ridge, Etau continued to intensify as it neared Japan. By August 11, the cyclone reached its peak intensity as a hurricane with winds of 75 km/h (45 mph 10-minute sustained) and a barometric pressure of 992 hPa (mbar). Shortly after, Etau began to weaken and was downgraded to a tropical storm early on August 11. Increasing wind shear led to the center becoming devoid of convection and the system eventually weakened to a tropical depression on August 13. The remnants of Etau persisted for nearly day before dissipating early on August 14. Although Etau did not make landfall, the outer bands of the storm produced torrential rainfall in Japan, peaking at . These rains triggered deadly flooding and mudslides, especially in Hyōgo Prefecture. Twenty-eight people were killed by the storm and ¥7.1 billion (US$87.5 million) in damage occurred throughout the affected region. According to the Fire and Disaster Management Agency, a total of 5,602 homes were flooded and 183 were destroyed. Following the storm, 600 Japanese soldiers were deployed from Tokyo to assist in cleanup efforts. ==Meteorological history== Tropical Storm Etau originated on August 5 out of an area of low pressure associated with disorganized convective activity located about 550 km (280 mi) east-northeast of Guam. The following day, the system relocated several dozen kilometers to the north. Convective turning began to appear on satellite imagery and a Tropical Upper Tropospheric Trough (TUTT) cell to the north provided a northward component to the system's movement. Early on August 7, the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert for the developing system as deep convection consolidated around the low pressure system. Around 0000 UTC on August 8, the Japan Meteorological Agency (JMA) designated the system as a tropical depression. Several hours later on August 8, the JTWC also declared the system a tropical depression, classifying it at 10W. Later that day, convection associated with the depression became disorganized, preventing intensification of the system. The depression generally tracked towards the northwest during the day in response a subtropical ridge to the north. By August 9, the center of circulation became more defined as convection wrapped around it. Around 1200 UTC, the JMA upgraded the depression to a tropical storm and gave it the name ''Etau''. The JTWC, however, did not upgrade the system to a tropical storm for several more hours. On August 10, the JTWC briefly downgraded the storm to a tropical depression. By this time, the system had re-curved to the east around the western periphery of the subtropical ridge. Etau also became slightly disorganized as it began to interact with the baroclinic zone near Japan. Early on August 11, the JMA reported that the storm winds had peaked at 75 km/h (45 mph 10-minute sustained) and a barometric pressure of 992 hPa (mbar). Later that day, the storm once more became slightly disorganized due to increased wind shear; however, the JTWC reported that the storm intensified based on satellite intensity estimates and weather radar imagery from Japan. Later on August 11, the center of Etau became partially devoid of convection, with only a narrow band of shower and thunderstorm activity persisting to the southeast of the center. Increasing wind shear prevented convection from redeveloping and the storm continued to weaken. Early the following day, the JTWC issued their final advisory on Etau as they reported it had weakened to a tropical depression well to the east of Japan. Roughly 24 hours later, the JMA also downgraded the system to a tropical depression. The final advisory on Etau was issued by the JMA early on August 14 as it slowly tracked northward. 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 Etau (2009)」の詳細全文を読む スポンサード リンク
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