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Typhoon Dot, known in the Philippines as Typhoon Saling, was the strongest storm of the 1985 season. Dot originated from a small area of thunderstorm activity in early to mid October. The system was first classified on October 11, and steadily intensified over the next few days. Dot attained typhoon strength on October 15, and subsequently entered a period of explosive deepening, which was not anticipated by forecasters. The next day the intensification rate slowed, but that evening, Dot attained its maximum intensify. A steady weakening trend began on October 17, though the system maintained typhoon intensity through the passage of the Philippines. After entering the South China Sea late on October 18, Dot briefly re-intensified, only to weaken as it approached Vietnam. On October 21, Dot struck Vietnam while still a typhoon, but dissipated next day over the high terrain of the nation. Although damage across the Philippines was less than initially expected, the typhoon lashed the nation with heavy rains. Nueva suffered the worst effects from Dot. There, of crops and 90% of all buildings were damaged. In Cabanatuan, 2,500 homes and 90% of structures were destroyed. Overall, 42 towns were flooded, forcing a total of 125,000 people to flee their homes, 35,000 of which were homeless. Furthermore, 52,933 houses were leveled while an additional 200,450 were damaged. Nationwide, 24 were hurt. While tracking through the South China Sea, Dot passed through Hainan Island. There, two casualties occurred while 34 others suffered injuries. Across the island, over 2,300 dwellings were destroyed. In all, Dot was responsible for 90 deaths and $104.9 million (1985 USD) in damage. ==Meteorological history== Following the extratropical transition of Typhoon Brenda on October 5, a mid-level subtropical ridge became centered over the northwestern Pacific, which resulted in an absence of the typical southwesterly monsoon flow typically seen during the autumn. Satellite imagery first detected an area of convection roughly southeast of Ponape on October 11. At 1200 UTC, the Japan Meteorological Agency (JMA) first identified the system. The next day, the storm's outflow became better defined as the storm tracked west-northwest. On October 13, wind shear began to decrease, and the cyclone developed a well-defined circulation. Based on this, the Joint Typhoon Warning Center (JTWC) upgraded the system into Tropical Storm Dot.〔 That evening, the JMA followed suit.〔 The newly upgraded Dot was situated in an area of strong easterly winds, and thus the JTWC correctly predicted to the system to continue west-northwest, despite forecasts from various tropical cyclone forecast models that showed otherwise.〔 Dot steadily strengthened during this period, and midday on October 14, the JMA classified Dot as a severe tropical storm.〔 Several hours later, the JTWC upgraded Dot into a typhoon, with the JMA following early on October 15. Around this time, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) also monitored the storm and assigned it with the local name ''Saling''. Shortly after attaining typhoon intensity, Dot entered a period of explosive intensification. However, this was not expected by meteorologists at the JTWC nor the forecast models due to the presence of dry air.〔 At 0600 UTC on October 15, the JTWC revised the intensity to , equivalent to a mid-level Category 2 hurricane on the United States-based Saffir-Simpson Hurricane Wind Scale (SSHWS). That evening, the JMA increased the intensity of Dot to , making it the strongest tropical cyclone of the season.〔 At 2300 UTC on October 15, Hurricane Hunters measured a minimum barometric pressure of , a drop in over the previous 23 hours, equal to a drop per hour. This rate exceeded the threshold of explosive intensification, which according to the JTWC, is per hour.〔 Based on the aforementioned aircraft reports, the JTWC increased the intensity to at 0000 UTC on October 16. By this time, Dot had developed a well-defined eye surrounded by very cold cloud tops.〔 However, the JTWC also noted that the both storm's radius of maximum winds and Central dense overcast were unusually small.〔 By October 16, Dot's rate of deepening had level off.〔 At midday, the JTWC estimated that Dot attained peak intensity of 〔 while the JMA placed the storm's wind speed at .〔 After maintaining this intensity until the morning of October 17, Dot started a gradual weakening trend〔 while passing directly over Samar Island and encountering increased wind shear. Around this time, radar imagery showed that Dot displayed a small pinhole eye in diameter.〔 On the afternoon of October 18, the typhoon made landfall along southern Luzon. At this time, the JTWC reported an intensity of and the JMA assigned the storm's intensity at .〔 That evening, Dot re-emerged into the South China Sea while still at typhoon intensity. Continuing west-northwest, Dot quickly became better organized. According to the JTWC, Dot reaches its secondary peak intensity of midday on October 20 while situated roughly south-southwest of Hong Kong.〔 Meanwhile, the JMA raised the storm's intensity to .〔 Also around this time, the typhoon existed PAGASa's warning zone. After brushing Hainan Island, Dot resumed weakening. Early on October 21, Dot moved ashore in northern Vietnam, around south of Hanoi.〔 At the time of its second landfall, the JTWC estimate Dot's intensity at , while the JMA estimate was lower, at .〔 Land interaction with the high terrain of the nation resulted in rapid weakening, and by 0000 UTC October 22, the JTWC ceased tracking Dot.〔 The JMA followed suit 12 hours later.〔 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 Dot (1985)」の詳細全文を読む スポンサード リンク
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