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Severe Tropical Cyclone Marcia was a Category 5 severe tropical cyclone that made landfall at its peak strength over central Queensland, near Shoalwater Bay on 20 February 2015. The cyclone went on to affect various areas including Yeppoon and Rockhampton. It reached Yeppoon as a Category 4 system, then traversed over the regional city of Rockhampton as a Category 3 system on the same day. Eventually, the cyclone weakened, moved southeast out to sea, then dissolved. Marcia caused at least A$750 million (US$590.5 million) worth of damage.〔(【引用サイトリンク】url=http://www.skynews.com.au/news/national/2015/02/25/cyclone-marcia-bill-rises-to--67m.html )〕 ==Meteorological history== The Australian Bureau of Meteorology (BoM) started to monitor a tropical low which developed within the monsoon trough to the southeast of Papua New Guinea on 15 February. The system drifted generally eastwards and developed slowly under moderate vertical wind shear, until the Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert early on 17 February when deep convection wrapping tightly into a well-defined centre. Late on the same day, the BoM began to issue technical bulletins and designated the tropical low as ''14U'', although the bureau initially forecasted that it would only intensify into a category 1 cyclone prior to landfall. The JTWC upgraded the partially exposed system to a tropical cyclone and designated it as ''13P'' early on 18 February, which also forecasted that it would intensify slightly. At 09Z, the BoM reported that the tropical low intensified into a category 1 tropical cyclone and named it ''Marcia'', as it had started to track southwestwards along the northwestern periphery of a low- to mid-layered subtropical ridge.〔 When Marcia intensified into a category 2 tropical cyclone at 00:00 UTC on 19 February, it had developed a central dense overcast with a consolidating eyewall because of weakening vertical wind shear. Thanks to very good poleward outflow into the westerlies, Marcia dramatically underwent rapid intensification and formed a clear eye, becoming a category 3 severe tropical cyclone at 05:00 UTC and a category 4 system at 08:00 UTC. Soon afterwards, it turned southwards along the western periphery of a subtropical ridge and reached peak intensity at 18:00 UTC as a category 5 severe tropical cyclone with 10-minute maximum sustained winds at 205 km/h (125 mph), featuring a very well-defined 35 km (20 miles) eye. Maintaining strength, Marcia made landfall over the coast near Shoalwater Bay at 22:00 UTC (08:00 AEST on 20 February). On 20 February, despite good poleward outflow, Marcia began to track southeastwards along the western periphery of the subtropical ridge and rapidly weaken due to land interaction and increasing vertical wind shear, yet the JTWC issued the final warning during sunset. The system weakened into a category 3 cyclone at 13:00 AEST (03:00 UTC), lost the severe tropical cyclone intensity at 17:00 AEST (07:00 UTC) and even weakened into a category 1 cyclone at 20:00 AEST (10:00 UTC). The BoM’s final technical bulletin of Marcia indicated that the cyclone had eventually weakened into a tropical low at 15:00 UTC (01:00 AEST on 21 February), with the asymmetric wind structure and unimpressive observations. The ex-tropical cyclone arrived in the Coral Sea from the southeast coast of Queensland on 21 February. The JTWC monitored Marcia again on 22 February and claimed that the system had become subtropical with gale-force sustain winds, when sea surface temperature (SST) was approximately 25ºC; moreover, satellite imageries also revealed a broad, exposed low-level circulation centre (LLCC) with deep convection displaced over the southeast periphery of the LLCC. Although it drifted northwards over warmer SST later, it was failed to intensify but weakened further. On 27 February, Marcia entered the responsible area of the Fiji Meteorological Service as a weak low-pressure system. The remnants were completely absorbed into a trough on 1 March. 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 Marcia」の詳細全文を読む スポンサード リンク
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