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Typhoon Betty, known in the Philippines as Typhoon Herming, was a powerful and destructive tropical cyclone that struck the Philippines in August 1987. The seventh typhoon and second super typhoon of the active typhoon season, it formed from the monsoon trough that spawned a tropical cyclone on August 8 while around positioned well to the east of the Philippines. It drifted northwestward, becoming a tropical storm on August 9 and a typhoon on August 10. Betty turned westward, where it rapidly intensified before attaining peak intensity on August 11. The next day, Typhoon Betty made landfall in the central Philippines. Betty weakened rapidly over the country, but restrengthened somewhat over the South China Sea. Land interaction weakened Betty slightly before it hit central Vietnam on August 16. The next day, Betty dissipated. Across the Philippines, Typhoon Betty brought widespread flooding, which resulted in severe destruction. Damage added up to $100 million (1987 USD). In the Maguindanao and Albay provinces alone, 10,000 people were evacuated and 1,000 were homeless. However, the capital city of Manila avoided any serious damage. Nationwide, around 200,000 people were reportedly homeless, 18,000 of winch were from Marinduque and another 11,400 resided on Mindoro Island. In the former, 4,000 dwellings sustained damage, and all of the banana crop there was lost. In all, 25,518 homes received damage. Roughly 400,000 people were directly affected by the storm. Overall, 85 people were killed and 324 others were wounded. After striking the Philippines, six people were killed by Betty in Vietnam. Approximately 10,000 structures were damaged and 103 people were injured. Elsewhere, in northern Thailand, one person was killed and three others were hurt by the typhoon. Several villages were flooded, and numerous streets were damaged. ==Meteorological history== The origins of Typhoon Betty can be traced back to a tropical disturbance that was embedded in the monsoon trough on August 7, which extended from the Marshall Islands westward to the Philippines. Intensity estimates via the Dvorak technique yielded winds of around north-northwest of Belau in the western Caroline Islands. Following a rapid increase in organization, the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert (TCFA) for the system early on August 8. Meanwhile, the Japan Meteorological Agency (JMA) started tracking the system. Around this time, the Philippine Atmospheric, Geophysical and Astronomical Services Administration also monitored the storm and assigned it with the local name ''Herming''. Early on August 9, Betty intensified into a tropical storm about 1,320 km (820 mi) east-southeast of Manila during the morning of August 9. Betty continued to intensify, and by midday, the storm attained winds of .〔 By the evening of August 9, the JMA upgraded Betty to a severe tropical storm.〔 At 0000 UTC on August 10, both the JMA and JTWC believed that Betty attained typhoon intensity.〔 Tracking westward Betty began an episode of explosive deepening as expected by the JTWC.〔 At noon, the JTWC reported that Betty attained winds of , equivalent to a Category 2 hurricane on the United States Saffir-Simpson Hurricane Wind Scale (SSHWS). By 0000 UTC on August 11, the agency upgraded Betty to an equivalent of a Category 4 hurricane.〔 Later that day, the JMA estimated that Betty attained its peak maximum sustained wind of and a minimum barometric pressure of . However, the JTWC indicated that the system was considerably stronger, with maximum sustained winds of 260 km/h (160 mph). This concluded the storm intensification period; according to the JTWC, Betty strengthened in a 37-hour time frame.〔 Furthermore, Betty was the deepest storm of the season,〔 and one of the most powerful storms ever recorded.〔 At peak, which it maintained for 12 hours,〔 Betty exhibited a small but well-defined eye surrounded by very cold cloud tops.〔 Thereafter, Betty began to weaken as it moved over the central Philippines. Accelerating, Betty continued on a westward track while passing south of a subtropical ridge. According to the JTWC, winds quickly decreased to , and by the time it emerged into the South China Sea early on August 13, the typhoon's winds had diminished to , equivalent to a high-end Category 2 on the SSHWS.〔 The JMA estimated that Betty was slightly weaker, with winds of .〔 Moving west-northwest, Betty began to deepen over open water.〔 By midday, the JMA increased the intensity of Typhoon Betty to .〔 On the morning of August 14, the JTWC remarked that Betty reached its secondary peak intensity of .〔 Despite this, intensity estimates from the JMA note that Betty did not intensify any further.〔 After attaining its secondary peak intensity, Betty began to deteriorate as it began to interact with Vietnam. After entering the Gulf of Tonkin, Betty made landfall south of Hanoi in northern Vietnam on August 16.〔 At the time of landfall, the JMA estimated winds of and the JTWC estimated winds of .〔 According to the JMA, Betty weakened to a tropical storm on evening of August 16.〔 It then swept across Laos and eventually dissipated over northern Thailand near Chiang Mai during the evening of August 17.〔(【引用サイトリンク】url=http://www.hko.gov.hk/publica/tc/tc1987.pdf )〕 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「Typhoon Betty (1987)」の詳細全文を読む スポンサード リンク
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