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Tropical Cyclone Kesiny was the first recorded tropical cyclone – the equivalent of a minimal hurricane – to make landfall in the month of May 2002 in the south-west Indian Ocean. The final named storm of the busy 2001–02 South-West Indian Ocean cyclone season, Kesiny formed on May 2 from a trough near the equator. Its formation was the result of an increase in the Madden–Julian oscillation, which also contributed to a twin storm in the north Indian Ocean that hit Oman, and another set of storms in northeast and southeast Indian Ocean. Kesiny initially moved to the southeast, but later turned to the southwest due to a strengthening ridge. On May 6, it intensified into a tropical cyclone, but later weakened and was not expected to re-strengthen. However, Kesiny developed an eye and re-intensified into a tropical cyclone on May 9, reaching peak winds of before striking Madagascar about southeast of Antsiranana. It weakened while crossing the country, and after turning to the south it struck the country again before dissipating on May 11. Across Madagascar, Cyclone Kesiny dropped heavy rainfall, reaching in three days at Toamasina, the second largest city in the country. The rains caused mudslides and flooding in the eastern portion of the country, wrecking the rice and maize crops and leaving 5,000 people homeless. At least 33 bridges were destroyed, and many roads were damaged. A total of 33 people were killed, and 1,200 people were injured. The cyclone struck in the midst of a political crisis, in which the top two candidates of the Malagasy presidential election in 2001 declared themselves the winner; the incumbent, who lost, declared Toamasina as the capital city, and the political instability disrupted relief efforts. ==Meteorological history== In late April 2002, an area of convection, or thunderstorms, persisted to the west-southwest of Diego Garcia in the south-central Indian Ocean, associated with a trough near the equator. The system had a broad circulation, and initially moved slowly to the east-southeast. It developed due to an increase in the Madden–Julian oscillation (MJO), which moved eastward across the Indian Ocean. The same system spawned a disturbance in the northern Indian Ocean that later struck Oman as a tropical cyclone. Such simultaneous systems in opposite hemispheres occasionally occur in the spring or autumn; in May 2002, the powerful MJO pulse produced two such sets of storms, later producing a set in the eastern Indian Ocean that became a deep depression that struck Myanmar and Tropical Storm Errol to the southwest of Indonesia. On April 30, Météo-France (MFR) classified the system as a zone of disturbed weather.〔 〕 It slowly organized, prompting the Joint Typhoon Warning Center (JTWC) to issue a tropical cyclone formation alert late on May 2,〔 around the time that MFR classified it as Tropical Disturbance 14.〔 The thunderstorms became more concentrated around an increasingly well-defined center, and with minimal wind shear, the system strengthened into Tropical Depression 14 on May 3.〔 That day, the JTWC initiated advisories on Tropical Cyclone 23S.〔 Developing rainbands and a central dense overcast, the depression intensified into Tropical Storm Kesiny early on May 4.〔 Gradual intensification continued, although initially the convection remained dislocated to the west of the center. The circulation later moved beneath the thunderstorms, and a strengthening ridge turned Kesiny toward the west-southwest.〔 Late on May 5, a ragged eye began forming within the convection, which was indicative of a strengthening storm.〔 That day, MFR upgraded Kesiny to a severe tropical storm.〔 Early on May 6, the JTWC upgraded the storm to the equivalent of a minimal hurricane, with maximum 1 minute sustained winds of 120 km/h (75 mph). Around that time the outflow became pronounced to the north and south, although a decrease in outflow caused Kesiny to weaken.〔 By May 7, the circulation was exposed from the convection,〔 and little re-intensification was expected. By that time, the storm was located about 650 km (400 mi) east of the northern tip of Madagascar.〔 Despite predictions for no further intensification, Kesiny redeveloped convection late on May 8 that organized into a central dense overcast. By early on May 9, another eye had developed, and the storm quickly intensified into a tropical cyclone, according to MFR. This occurred despite little change in atmospheric conditions, although outflow had improved. Later on May 9, Kesiny struck northeastern Madagascar about southeast of Antsiranana, with peak winds of . This made it the first known tropical cyclone on record to make landfall in the month in the basin.〔 While crossing northern Madagascar, the eye quickly dissipated, and the winds decreased. Although re-intensification was expected over the Mozambique Channel, Kesiny remained weak while turning toward the south.〔 On May 10, the storm weakened to a tropical depression,〔 and subsequently it made a second landfall about northeast of Mahajanga.〔 Kesiny dissipated on May 11 while inland.〔 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「Cyclone Kesiny」の詳細全文を読む スポンサード リンク
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