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Cyclone Bola was one of the costliest cyclones in the history of New Zealand,〔 causing severe damage as an extratropical cyclone when it passed near the country in March 1988. It formed on February 24 to the north of Fiji, and tracking generally southwestward it reached hurricane-force winds near Vanuatu on February 28. The next day it generated peak wind velocities of 195 km/h (120 mph), though it quickly weakened as it accelerated southward. On March 4 Bola transitioned into an extratropical storm, passing to the north of the North Island of New Zealand on March 8. It weakened further and was absorbed by a stationary trough near the South Island on March 12. The cyclone first affected Fiji, where it produced gale force winds and strong waves. In Vanuatu, Bola dropped heavy rainfall, which destroyed two bridges and caused severe damage to islands in the group. Bola caused severe damage to the North Island of New Zealand, where heavy rainfall peaked at 917 mm (36.1 in) in Gisborne Region. Damage totaled over $82 million (1988 USD).〔 Three people were killed due to flooding, and hundreds were evacuated when a swollen river threatened Wairoa. In Whangaruru Harbor Northland a samaritan act accounted for another Bola fatality when an elderly male long time resident of Rapata road Oakura Bay attempted to tie down a neighbours empty water tank. He suffered a massive heart attack and died during the peak of the storm. The name ''Bola'' was later retired, meaning it will not be used again within the same basin. ==Meteorological history== On February 24, 1988, the Fiji Meteorological Service's Nadi Tropical Cyclone Warning Center (TCWC Nadi) started to monitor a tropical depression that had developed within the South Pacific Convergence Zone to the north-northeast of Suva, Fiji. During that day the system moved towards the southwest, before the Joint Typhoon Warning Center (JTWC) initiated warnings on the system and designated it as Tropical Cyclone 13P after it had become equivalent to a tropical storm. Over the next 2 days the system gradually developed tropical cyclone characteristics as it moved south-westwards and passed to the northwest of Fiji.〔 Early on February 26, TCWC Nadi named the system Bola after it had become equivalent to a modern-day category 1 tropical cyclone on the Australian tropical cyclone intensity scale. The system initially moved south-westwards which seemed to indicate to the Vanuatu Meteorological Service, that the islands of Maewo and Pentecost were in some danger.〔 However, as Bola moved further southwards it entered a region of light and variable winds, which along with an area of high pressure in the Tasman Sea blocked Bola's movement southwards.〔 As a result, the systems future movement became hard to predict early on February 27 as it became slow moving.〔 By this time Bola had become a category 2 tropical cyclone on the Australian scale, with wind speeds of between occurring near the center.〔〔 On February 28 the Joint Typhoon Warning Center (JTWC) assessed the cyclone as reaching hurricane-force winds near Vanuatu. It turned to a southeast drift before executing a small cyclonic loop on March 1, during which the JTWC estimated Bola attained peak winds of 195 km/h (120 mph). At the same time, its minimum central pressure was estimated at 940 mbar.〔 〕 After reaching peak intensity, Cyclone Bola quickly weakened as it accelerated southeastward toward a frontal trough.〔〔 On March 3, its winds dropped below hurricane-force,〔 and it gradually lost its tropical characteristics. The structure became asymmetric, with a large band of clouds extending well south of the circulation. By March 4, Bola had completed the transition into an extratropical cyclone.〔 Which turned south and began to affect the North Island of New Zealand on March 6. A building ridge of high pressure to its south caused the extratropical remnants of Bola to slow and turn to the west on March 7. The next day, the storm passed about 110 km (70 mi) north of the North Island. Around the same time, the storm began slowly filling, meaning the low pressure area associated with Bola was losing its identity. It turned southward on March 9, and on March 12 was absorbed by a stationary trough in the Westerlies near the western coast of the South Island.〔 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 Bola」の詳細全文を読む スポンサード リンク
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