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Severe Tropical Storm Mekkhala, known in the Philippines as Tropical Storm Amang, was an early-season tropical cyclone that made landfall over the Philippines in January 2015. Mekkhala killed three people and disturbed Pope Francis’ visit to the country. Although the storm also caused an airplane crash in Tacloban, nobody was hurt in the incident. The system developed into a tropical storm on January 14.〔 However, Mekkhala intensified very slowly due to its exposed center and the marginal conditions, until it began to strengthen rapidly on January 16.〔 It then made landfall over Samar on January 17.〔 Owing to land interaction, Mekkhala weakened into a tropical storm within six hours, and it further weakened into a tropical depression on January 18 under strong vertical wind shear.〔〔 ==Meteorological history== A tropical disturbance formed approximately 390 km (240 miles) south-southwest of Pohnpei early on January 9.〔(【引用サイトリンク】url=http://www.nrlmry.navy.mil/tcdat/tc15/WPAC/01W.MEKKHALA/ir/geo/1km/ )〕 The system remained disorganized until the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert to it late on January 12, when deepened convection with formative started to wrap into a slowly-consolidating low-level circulation center (LLCC). Afterwards, the Japan Meteorological Agency (JMA) upgraded the low-pressure area to a tropical depression early on January 13, as did the JTWC with the designation ''01W'' Although deep convection was displaced to the northwest of an exposed LLCC early on January 14, the JMA still upgraded the system to a tropical storm and named it ''Mekkhala'', under moderate vertical wind shear offset by excellent poleward outflow. In post-season analysis, the agency upgraded the storm at 12:00 UTC on the previous day. Late on January 14, the PAGASA named the storm ''Amang'' right after it entered the Philippine Area of Responsibility. Tracking west-northwestward and then westward along the southern periphery of a subtropical ridge, Mekkhala was upgraded to a tropical storm by the JTWC early on January 15, due to its slightly improved structure. Mekkhala quickly intensified on the next day due to improved conditions; the wind shear became in-phase with the storm's motion while the robust divergent outflow persisted. Therefore, the JMA upgraded the system to a severe tropical storm at 06:00 UTC on January 16,〔 and later that day the JTWC upgraded it to a typhoon, when a central dense overcast has significantly deepened and totally obscured the LLCC.〔 Later, a microwave imagery revealed that Mekkhala formed a ragged eyewall structure. The system reached peak intensity at 00:00 UTC on January 17 with ten-minute maximum sustained winds of 110 km/h (70 mph),〔 although operationally the JMA estimated typhoon-force winds of 130 km/h (80 mph). After slightly weakening, Mekkhala tracked northwestward and made landfall over Dolores, Eastern Samar of the Philippines at around 15:00 Philippine Standard Time (07:00 UTC), where Typhoon Hagupit also made landfall the month before. Both the JMA and the JTWC downgraded Mekkhala to a tropical storm on January 17, due to land interaction weakening the storm significantly. Mekkhala eroded further while crossing the Bicol Region on January 18, leading the JTWC to downgrade it to a tropical depression when it turned northward and emerged into the Philippine Sea. Late on the same day, the JMA downgraded Mekkhala to a tropical depression, and shortly after the JTWC issued the final warning as strong wind shear exposed the LLCC. The tropical depression drifted northeastward and maintained its exposed low-level circulation east of Luzon, until the system was completely absorbed by a stationary front early on January 21. 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 Mekkhala (2015)」の詳細全文を読む スポンサード リンク
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