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Intense Tropical Cyclone Dina was a cyclone that caused record flooding across parts of Réunion. Originating from a tropical disturbance on 15 January 2002 near the Chagos Archipelago, the precursor to Dina quickly developed within a region favoring tropical cyclogenesis. By January 17, the system had developed enough organized convection as it moved southwestward to be declared a tropical depression. Rapid intensification occurred shortly thereafter, with the system attaining winds in excess of 120 km/h (75 mph) on January 18. Dina achieved its peak intensity on January 20 as an intense tropical cyclone winds of 215 km/h (130 mph). Hours after reaching hits strength, the storm bypassed Rodrigues Island about to its north. On January 21, the storm brushed Mauritius and Réunion as an intense tropical cyclone before turning southward. Once on a southward course, steady weakening ensued and the system eventually transitioned into an extratropical cyclone on January 25. The remnants of the storm accelerated southeastward and were last noted on January 28 before being absorbed into a polar trough. Across Mauritius and Réunion, torrential rains and destructive winds from the cyclone resulted in extensive to "catastrophic" damage. The entire island of Mauritius lost power during the storm and widespread structural damage took place. Agricultural and property damage amounted to US$47 million and US$50 million respectively in the republic. Nine fatalities were attribute to the storm in Mauritius: five off the coast of Rodrigues Island and four on the main island. More extensive damage was seen on Réunion where up to of rain fell over three days. Record to near-record flooding destroyed many homes, washed out roads, and caused catastrophic agricultural damage. Destructive winds, measured up to also crippled communications. In all, six people died on the island and losses were estimated at €200 million (US$190 million). ==Meteorological history== On January 15, a tropical disturbance began organizing near the Chagos Archipelago in the South Indian Ocean convergence zone, which is an extended area of convection connected to the monsoon. The thunderstorms gradually organized,〔 associated with a weak circulation and located within an area of moderate wind shear.〔 A distinct low pressure area developed on January 16, about east of Diego Garcia. The thunderstorms were primarily located along the western periphery due to continued shear, and ordinarily would prevent significant development. The system moved to the southwest along the north side of a ridge, and despite the shear it developed into a tropical disturbance late on January 16. Subsequently, the system rapidly organized,〔 developing rainbands as the convection increased.〔 At 0000 UTC on January 17, Météo-France (MFR) upgraded the disturbance to a tropical depression, and six hours later upgraded the system further to Tropical Storm Dina.〔 〕 Shortly thereafter, the Joint Typhoon Warning Center (JTWC) issued a tropical cyclone formation alert,〔 and later that day initiated advisories about 425 km (265 mi) south of Diego Garcia. Dina quickly intensified, and its T-numbers using the Dvorak technique increased by 0.5 every six hours during the storm's development phase.〔 An eye began developing late on January 17,〔 and at 1200 UTC on January 18, MFR upgraded Dina to a tropical cyclone, or the equivalent of a Category 1 hurricane on the Saffir-Simpson Hurricane Scale. This was only 36 hours after it was first classified as a tropical disturbance, which is much less than the five days most tropical cyclones take.〔 About three hours earlier, the JTWC had also upgraded the storm to tropical cyclone status.〔 The small eye of Dina, only in diameter,〔 quickly became well-defined,〔 although it became obscured by the central dense overcast on visible satellite imagery.〔 On January 19, the cyclone slowed as it turned to the west-southwest, after the ridge to its south intensified.〔 The intensification rate briefly slowed, before Dina rapidly intensified late on January 19,〔 becoming an intense tropical cyclone early the next day.〔 Surrounded by an eyewall of deep convection, Dina intensified to reach its peak intensity on January 20. Based on satellite intensity estimates between , the JTWC estimated peak one-minute sustained winds of 240 km/h (150 mph), about north-northeast of Rodrigues Island. At around the same time, MFR estimated peak ten-minute winds of 215 km/h (130 mph).〔 While at its peak, Dina had a very symmetrical structure, and gusts were estimated to have reached .〔 On January 20 while near peak intensity, Dina slowed its movement further and moved more toward the west. After previously being in the projected track of the cyclone, Rodrigues Island was bypassed by the cyclone passing about to its north. After passing by the island, Dina underwent an eyewall replacement cycle, which resulted in an outer eyewall forming and replacing the previous, smaller one. This resulted in the cyclone weakening slightly, although it retained much of its intensity while tracking toward Mauritius and Réunion. Late on January 21, Dina passed about north of Cape Malheureux in Mauritius, with 10-minute winds estimated at 185 km/h (115 mph); however, the strongest winds remained offshore.〔 At the time, the storm's eye became asymmetric with a diameter of . Late the next day, Dina also passed about off the north coast of Réunion, and although the island was in the forecast track, the cyclone accelerated to the west in the final hours and spared the island from the strongest winds. This abrupt shift in tract took place as the cyclone interacted with the high terrain of Réunion. Additionally, Doppler weather radar showed the highest reflectivity values to be from the center.〔 On January 23, Dina weakened below intense tropical cyclone status while it accelerated to the southwest;〔 the change in movement was due to the ridge moving further to the southeast. Increased wind shear due to an approaching trough contributed to the weakening, and by late on January 23 the eye dissipated. The next day, Dina weakened into a tropical storm, after the convection diminished around the center.〔 Late on January 24, the JTWC discontinued advisories,〔 and about 24 hours later, MFR classified Dina as an extratropical cyclone.〔 The system accelerated to the southeast and was absorbed by a polar trough on January 28.〔 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 Dina」の詳細全文を読む スポンサード リンク
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