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Typhoon Bess, known in the Philippines as Typhoon Susang, was responsible for the disappearance of a United States Air Force weather reconnaissance aircraft. Developing out of a poorly organized system on October 8 to the east of the Philippines, Bess featured two centers of circulation. Initially the southern low was monitored; however, a low to the north soon became the dominant center. Tracking generally west-northwestward, the storm gradually intensified before striking northern Luzon as a minimal typhoon on October 11. Temporary weakening took place due to interaction with land. After moving back over water the following morning, Bess regained typhoon intensity. This was short-lived though, as conditions surrounding the cyclone soon caused it to weaken. Now moving due west, the weakening storm eventually struck Hainan Island as a tropical storm on October 12 before diminishing to a tropical depression. The depression briefly moved back over water before dissipating in northern Vietnam on October 14. Bess produced heavy rains throughout the Philippines, especially in Luzon where was measured in Baguio. These rains triggered extensive flooding and landslides that killed 26 people and left 3 others missing. Many homes were destroyed and damage amounted to $9.2 million (1974 USD). On October 12, a reconnaissance plane, with a crew of six, investigating the periphery of the storm went missing. It's presumed that the entire crew was lost when the aircraft crashed off the coast of Luzon. Though the center remained offshore, strong winds and high tides also impacted Hong Kong, causing minor flooding. ==Meteorological history== On October 6, 1974, the Joint Typhoon Warning Center (JTWC) began monitoring a tropical disturbance several hundred miles southeast of Guam. Tracking quickly westward to west-northwestward in response to a strong subtropical ridge to the north, the system gradually organized, passing near Ulithi atoll on October 7. Accompanied by a broad monsoonal flow, the disturbance featured multiple centers of circulation. On October 8, it developed into a tropical depression and soon into a tropical storm, at which time it was assigned the name ''Bess''. Early on October 9, an aircraft reconnaissance mission into Bess revealed that a new dominant center of circulation had developed to the north of the original low. The southern low soon dissipated as the northern one became a tropical storm. The northern system retained the name Bess and is considered the same storm by the JTWC. After the northern circulation became the dominant center on October 9, a deepening trough in the westerlies caused a decrease in synoptic pressures, resulting in Bess' forward motion greatly decreasing.〔 Maintaining a west-northwesterly track, strong outflow developed, especially to the southwest of the circulation.〔 The storm eventually intensified into a typhoon on October 10 as it approached the northern Philippines.〔 Due to the cyclone's proximity to the country, the Philippine Atmospheric, Geophysical and Astronomical Services Administration also monitored the storm and assigned it with the local name ''Susang''. Later that day, Bess made landfall in northern Luzon, roughly 95 km (60 mi) south of Escarpada Point, with winds estimated at 120 km/h (75 mph). Though classified a minimal typhoon by the JTWC,〔 the Hong Kong Royal Observatory reported that reconnaissance planes had recorded surface winds of 140 km/h (85 mph) before the system moved ashore. Inland, a barometric pressure of 976.9 mbar (hPa; 28.85 inHg) was recorded in Tuguegarao as the typhoon passed 55 km (35 mi) to the north.〔 Due to the interaction with the high terrain of northern Luzon, Bess temporarily weakened to a tropical storm before regaining typhoon strength over the South China Sea during the afternoon of October 11.〔 As the storm emerged back over water, satellite images revealed a relatively large system with clouds spanning an area 485 km (300 mi) in diameter.〔 Upon reintensifying, Bess turned due west in response to a dominating high pressure area over Southern China. With a large difference in pressures between the two systems, a strong northeasterly flow developed between them.〔 This resulted in gale-force winds occurring up to 400 km (250 mi) from Bess's center.〔 During the evening of October 12, the combined effects of a winter monsoon and entrainment of cool, dry air from mainland China began to weaken the system. By the following morning, Bess had weakened to tropical storm as it passed 305 km (190 mi) south of Hong Kong.〔〔 The system later struck Hainan Island with winds of 85 km/h (50 mph) before lessening to a tropical depression. The dissipating system emerged over the Gulf of Tonkin on October 14 and ultimately dissipated as it began moving ashore in northern Vietnam later that day.〔 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 Bess (1974)」の詳細全文を読む スポンサード リンク
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