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Intense Tropical Cyclone Funso was a powerful tropical cyclone which produced flooding in Mozambique and Malawi in January 2012. It was the eighth tropical cyclone, the sixth named storm and the second tropical cyclone to form during the 2011–12 season. Funso was also the first intense tropical cyclone since Bingiza in 2011 and the first storm to affect Mozambique since Jokwe in 2008. ==Meteorological history== The origins of Cyclone Funso were from an area of convection in the Mozambique Channel. On January 17, a low-level circulation developed in the area as the convection organized into intense rainbands. An upper-level anticyclone provided favorable conditions for development, including weak wind shear and good outflow. The system encountered warm sea surface temperatures, and favorable inflow from the south of its circulation was expected to increase after Subtropical Depression Dando dissipated over southern Africa. Late on January 18, the Joint Typhoon Warning Center (JTWC) issued a tropical cyclone formation alert, indicating a high chance of the system becoming a tropical cyclone. At 0000 UTC the next day, Météo-France (MF) classified it as Tropical Disturbance 8 about halfway between Mozambique and Madagascar in the northern Mozambique Channel. About six hours later, the agency upgraded the disturbance to a tropical depression, after the convection became better organized. The JTWC had also begun issuing advisories on the system by that time, labeling it Tropical Cyclone 08S. Upon forming on January 19, the depression was moving to the southwest along the northern edge of a ridge.〔 Though the system's low-level structure was disorganized, it gradually improved over the course of the day;〔 MF upgraded the system to Moderate Tropical Storm Funso at 1200 UTC on January 19, or about 12 hours after its formation. Around that time, there was a warm spot, or a precursor to an eye, in the middle of a circular area of convection. Funso rapidly intensified after the eye became better established, and the MF upgraded the storm to a tropical cyclone – the equivalent of a 120 km/h (75 mph) hurricane – early on January 20. By that time, the outflow had increased significantly, partly due to an upper-level trough providing ventilation to the southeast. Shortly after Funso intensified into a tropical cyclone, the eye disappeared on satellite imagery, although this was due to the small size of the eyewall. Further intensification was forecast to be limited by the cyclone's interaction with the coast of Mozambique, as well as upwelling from its slow movement. On January 20, Funso turned to the west and slowed, due to its position between a ridge to the northwest of Madagascar and another ridge near the Mozambique-South Africa border. The convection to storm's west over land diminished while the center remained well-organized. Despite land interaction, Funso intensified further, and the JTWC assessed 1 minute winds of 185 km/h (115 mph) early on January 21, based on the appearance of a well-defined eye 15 km (9 mi) in diameter. Around the same time, MF estimated the storm attained 10 minute maximum sustained winds of 165 km/h (105 mph), making Funso an intense tropical cyclone. At the time, the storm was located about 110 km (70 mi) east of Quelimane, Mozambique, and its movement was nearly stationary.〔 By late on January 21, however, Funso weakened due to land disrupting the convection. A building ridge to the north forced the cyclone to the southeast into an area favorable for re-intensification. As the storm moved away from the Mozambique coastline, the convection became better organized, and the eye gradually reformed. Minimal wind shear, excellent outflow, and water temperatures of at least allowed for significant strengthening. Late on January 23, the JTWC estimated 1 minute sustained winds of 215 km/h (135 mph), and the agency forecast further strengthening to 260 km/h (160 mph). Early the next day, MF estimated 10 minute sustained winds of 195 km/h (120 mph) about 330 km (200 mi) southeast of Quelimane, Mozambique. After reaching peak intensity, Funso turned toward the southwest due to a building ridge to its east. Late on January 24, the cyclone began an eyewall replacement cycle, which initiated a brief weakening trend. MF remarked that Funso weakened below intense tropical cyclone intensity early on January 25. At the same time, the JTWC estimated the cyclone intensified further to peak 1 minute sustained winds of 220 km/h (140 mph), based on estimates via the Dvorak technique. The agency noted that the eyewall replacement cycle finished and produced a well-defined eye 28 km (17 mi) in diameter. At 1200 UTC on January 25, MF again upgraded Funso to an intense tropical cyclone, and later that day the cyclone began another eyewall replacement cycle, and developed a larger eye measuring 55 kilometers across. Funso underwent another eyewall replacement cycle on January 27 as it started weakening. On January 27, the government of Mozambique formally announced that the cyclone had begun to gradually weaken in the early-morning hours. Cyclone Funso is slated to pose no imminent threat to the northeastern coast of South Africa. On January 28, Funso weakened rapidly and transitioned into an extratropical cyclone, due to strong vertical wind shear, and colder sea surface temperatures below 25°C. 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 Funso」の詳細全文を読む スポンサード リンク
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