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Cyclone Forrest, also referred to as Typhoon Forrest,〔 was a powerful tropical cyclone that prompted the evacuation of 600,000 people in Bangladesh in late November 1992. Originating from an area of disturbed weather near the Caroline Islands on November 9, Forrest was classified as a tropical depression three days later over the South China Sea. Tracking generally west, the system steadily organized into a tropical storm, passing Vietnam to the south, before striking Thailand along the Malay Peninsula on November 15. Once over the Bay of Bengal, Forrest turned northward on November 17 and significantly intensified. It reached its peak intensity on November 20 as a Category 4-equivalent cyclone on the Saffir–Simpson hurricane scale with winds of 230 km/h (145 mph). Hostile environmental conditions soon affected the cyclone as it turned abruptly east-northeastward. Forrest made landfall in northwestern Myanmar as a weakening system on November 21 before dissipating early the next day. The majority of deaths associated with Forrest resulted from a plane crash on November 14 in Vietnam which killed 30 of the 31 occupants. In Thailand, the system produced significant storm surge, damaged or destroyed 1,700 homes, and killed two people. Agricultural losses in the hardest hit areas were estimated at ฿800 million (US$32 million). On November 20, as Forrest reached its peak intensity, fears arose across Bangladesh that a repeat of the catastrophic April 1991 cyclone would take place. As a result, mass evacuation plans were enacted across coastal areas of the country, with plans to relocate up to 2 million people. But the storm abruptly turned eastward, and the successful evacuation of 600,000 residents spared countless lives. Only two deaths were recorded and overall damage was light, though half of all homes on St. Martin's Island were damaged. ==Meteorological history== The second of four notable tropical cyclones in the Western Pacific in early November 1992, Forrest was first identified as an area of disturbed weather over the western Caroline Islands on November 9. Moving generally west-northwest, convection associated with the system steadily organized and the Joint Typhoon Warning Center (JTWC) subsequently issued a Tropical Cyclone Formation Alert (TCFA) on November 10. Development into a tropical depression was not anticipated until the system cleared the Philippines; however, organization was slower than forecast and a second TCFA was issued late on November 11. Once west of Palawan Island and over the South China Sea on November 12, the convective structure rapidly consolidated. The disturbance was designated ''Tropical Depression 30W'' at 12:00 UTC,〔 when it was 940 km (585 mi) east-southeast of Ho Chi Minh City, Vietnam.〔 The Japan Meteorological Agency (JMA) followed suit six hours later. Moving toward the west-southwest, the system steadily organized; later that day, it attained gale-force winds and was assigned the name ''Forrest'' by the JTWC.〔 As the storm approached Vietnam, it turned southwest and moved parallel to the coast before resuming its westerly track. Forrest made its closest approach to the nation on November 14, passing 110 km (70 mi) south of Cà Mau Province.〔 The storm's proximity to land inhibited intensification, and it attained winds of 100 km/h (65 mph) as it moved over the Gulf of Thailand on November 14. The next day, the storm made landfall in the Nakhon Si Thammarat Province of Thailand.〔〔 While crossing the Malay Peninsula, Forrest lost most of its convection, though its circulation remained well-defined. Failing to reorganize, the system continued to weaken as it moved across the Andaman Sea.〔 At 06:00 UTC on November 16, the India Meteorological Department (IMD) began tracking the system as Depression BOB 08, although the agency quickly upgraded it to a deep depression and later a cyclonic storm. Two days later, a subtropical ridge over Southeast Asia nudged Forrest toward the north, and it regained organized convection. Early on November 18, the storm attained hurricane-force winds as favorable outflow and upper-level winds aided intensification. Strengthening continued through early on November 20, at which time Forrest reached its peak intensity with winds of 230 km/h (145 mph), a Category 4-equivalent cyclone on the Saffir–Simpson hurricane scale.〔 The IMD assessed three-minute sustained winds to have been 185 km/h (115 mph), making it a modern-day "extremely severe cyclonic storm", and its barometric pressure was estimated at 952 mbar (hPa; 28.11 inHg).〔 Forrest maintained its peak intensity for six hours before increasing wind shear disrupted it. Unexpectedly, the storm turned sharply northeast later on November 20, sparing most of Bangladesh from a direct hit. More dramatic weakening ensued on November 21 as Forrest neared landfall,〔 with its eye becoming obscure.〔 〕 The cyclone made landfall along the northern coast of Rakhine State in Myanmar between 06:00 and 12:00 UTC with winds of 155–175 km/h (100–110 mph).〔 The IMD estimated Forrest to have been far weaker as it moved ashore, reporting peak three-minute winds to be 85 km/h (50 mph) at that time.〔 Once onshore, the high terrain of northern Myanmar further eroded the cyclone's circulation. Forrest dissipated early on November 22 over the Magway Region.〔 Throughout the storm's existence in the Bay of Bengal, it was monitored by the ERS-1 satellite. It became the first North Indian Ocean cyclone to be observed by scatterometer instruments, providing the data necessary to calibrate the device for minimizing directional ambiguity of its measurements. 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 Forrest」の詳細全文を読む スポンサード リンク
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