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Cyclone Bejisa was a tropical cyclone that affected the islands of Réunion and Mauritius in early January 2014. In late December 2013, a tropical disturbance developed to the north of Madagascar. With favorable conditions, the low developed into a disturbance and soon into a depression on December 28. The system continued to develop and intensified into Moderate Tropical Storm Bejisa on December 29, with rapid intensification occurring. It developed into an Intense Tropical Cyclone on December 30, reaching peak maximum sustained winds of 165 km/h (105 mph). Due to an eyewall replacement cycle, Bejisa weakened, but re-intensified to a secondary peak of 160 km/h (100 mph) on January 1. Increased wind shear weakened the eyewall, which passed within 15 km (9 mi) of Réunion. After having moved generally south-southeastward for much of its duration, Bejisa turned to the southwest on January 3, by which time it had weakened to tropical storm status. It became a post-tropical cyclone on January 5 after the convection weakened over the center, and Bejisa became extratropical the next day as it meandered southwest of Madagascar. In its formative stages, Bejisa brought heavy rainfall to Seychelles, and it also dropped rainfall in Mauritius and Madagascar. Effects were worst on Réunion, where wind gusts were around 130–150 km/h (80–90 mph) along the coast. The storm also dropped torrential rainfall, peaking at at a volcano in Cilaos. The winds and rains downed many trees and power lines, which blocked roads and left 181,000 people without power. About 49% of the island also lost water supply. Bejisa left heavy damage to the agriculture industry, mainly to vanilla and sugar cane, totaling €63 million (US$85.2 million) in losses. The commune of Saint-Paul sustained moderate damage, with losses estimated at €3 million (US$4 million). Bejisa killed one person on the island due to head trauma, and there were 16 injuries. Later, the cyclone produced high waves in South Africa. ==Meteorological history== In late December 2013, computer forecast models began to predict the development and cyclogenesis of a disturbance within the monsoon trough north of Madagascar. At 1800 UTC on December 27, the Joint Typhoon Warning Center (JTWC) noted a discrete area of disturbed weather approximately north-northwest of Réunion that corresponded with model forecasts and had the potential to develop. Accompanied by a low-level circulation center, the monitored storm complex developed rainbands about its southern periphery the following day. At 1200 UTC on December 28, Météo-France deemed the system sufficiently organized to be considered a tropical disturbance, the fourth system to be given such a classification by the agency that season. Upon its designation, the disturbance was analyzed to have an unusually high barometric pressure, based on nearby weather station observations. Météo-France projected for the system to peak as a tropical cyclone before slightly weakening and impacting the Mascarene Islands. Tracking southward, the disturbance steadily organized following December 28. As a result of wind shear, the system's low-level circulation center remained partially exposed, though the shearing conditions were expected to lessen At 0000 UTC on December 29, the disturbance was upgraded to a tropical depression. At 1800 UTC that day, the depression intensified to moderate tropical storm intensity, thus receiving the name ''Bejisa'' by the Mauritius Meteorological Services. This coincided with the improving satellite appearance of the storm's central dense overcast.〔 Intensification subsequently quickened, and at 0600 UTC the next day Bejisa was considered to be a severe tropical storm. Concurrently a strengthening ridge in the mid-levels of the troposphere began to steer the storm towards the south-southeast. Following the development of a small pinhole eye, Bejisa was upgraded to tropical cyclone status at 1200 UTC on December 30, followed by intense tropical cyclone status six hours thereafter, with peak winds of 165 km/h (105 mph). In addition, the JTWC estimated 1–minute winds of 195 km/h (120 mph), utilizing the Dvorak technique to estimate the intensity. The agency noted that decreasing wind shear, favorable outflow, and warm sea surface temperatures allowed for the intensification. At that time of the peak winds, Bejisa was located about 825 km (515 mi) north-northwest of Réunion. The intensification phase of Bejisa was short-lived, as an eyewall replacement cycle resulted in a slight deterioration and fluctuation of the storm's organization and structure. On December 31, the system weakened below intense tropical cyclone status as the eye became less organized. When the eyewall replacement cycle completed, the eye became larger and the winds increased. Late on December 31, Bejisa passed about 125 km (75 mi) west of Tromelin Island. On the next day, the cyclone attained a secondary peak intensity of 160 km/h (100 mph). However, increasing wind shear eroded the eyewall, which opened the eyewall in the northern periphery. Despite Météo-France assessing that Bejisa had weakened, at the same time the JTWC estimated that the cyclone had intensified further to reach peak 1–minute winds of 205 km/h (125 mph) on January 2. That day, the storm's center passed within 155 km (95 mi) of Réunion while continuing to the southeast, and the eyewall passed within 15 km (9 mi) of the island. Continued wind shear stripped the convection, coupled with cooler water temperatures, and early on January 3, Bejisa weakened below tropical cyclone status. By that time, the ridge to the southeast turned the storm to the southwest. A slight decrease in wind shear was expected to allow the convection to rebuild on January 4, and the storm strengthened slightly. By January 5, Bejisa began evolving into a post-tropical cyclone, with weaker convection over the center. That day, Météo-France reclassified Bejisa as a post-tropical depression, noting that the radius of maximum winds had expanded. On the same day, the JTWC discontinued warnings after assessing that the storm had become a subtropical cyclone. Increasing wind shear displaced the remaining convection west of the center, and Météo-France discontinued advisories on Bejisa on January 6 after the exposed turned more to the south. The storm became extratropical and turned to the northeast, and was last noted on January 7. 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 Bejisa」の詳細全文を読む スポンサード リンク
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