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Tropical Cyclone Herbie was the only known tropical system to impact Western Australia during the month of May on record. The final cyclone of the 1987–88 Australian region cyclone season, Herbie was first identified northwest of the Cocos Islands on 17 May. The following day, the system was classified as a tropical low by the Australian Bureau of Meteorology and intensified into a Category 1 cyclone later that day. Several hours after this upgrade, the storm attained its initial peak intensity with winds of 75 km/h (45 mph 10-minute sustained). Around the same time, the Joint Typhoon Warning Center classified Herbie as Tropical Storm 21S. On 19 May, the cyclone formed a new low pressure center and relocated roughly south. Shortly thereafter, the storm began to accelerate towards the southeast and started to undergo an extratropical transition. Early on 21 May, Herbie made landfall in Shark Bay before losing its identity the following day over the Great Australian Bight. Although a weak storm, Herbie brought flooding rains and severe dust storms to portions of Western Australia. Additionally, a 30,000 ton freighter broke in half amidst rough seas produced by the storm. Total losses from the storm reached A$20 million ($15.6 million USD). Due to the significant damage wrought by Herbie, the name was retired following its use. ==Meteorological history== Tropical Cyclone Herbie originated from an area of low pressure on 17 May 1988 northwest of the Cocos Islands. Later that day, the Australian Bureau of Meteorology began monitoring the system as a tropical low. Several hours after, the Joint Typhoon Warning Center (JTWC) classified the system as Tropical Depression 21S, having attained winds of 45 km/h (30 mph 1-minute sustained). Following slight development, the system intensified into a Category 1 cyclone and was given the name Herbie by the Australian Bureau of Meteorology early on 18 May.〔 Several hours after being named, the storm attained its initial peak intensity with winds of 75 km/h (45 mph 10-minute sustained) and a barometric pressure of 990 hPa (mbar).〔 Around the same time, the JTWC upgraded the system to a tropical storm, estimating the cyclone to have attained peak winds of 65 km/h (40 mph 1-minute sustained).〔 On 19 May, satellite imagery of the system depicted that a new low pressure centre had developed roughly south of the original low.〔 Several hours after the relocation, the JTWC downgraded Herbie to a tropical depression as the system's movement began to accelerate towards the southeast.〔〔 As the storm moved at a rapid speed towards the coastline of Western Australia, it began to undergo an extratropical transition. During a 24-hour period (20–21 May) Herbie tracked roughly , with the movement of the storm reaching at times.〔 Late on 20 May, the JTWC ceased advisories on the system as it weakened below tropical depression status offshore.〔 However, the Bureau of Meteorology continued to monitor the system. Early on 21 May, the center of Herbie made landfall in Shark Bay with wind gusts up to 120 km/h (75 mph) and a pressure of 980 hPa (mbar). Due to the rapid movement of the storm, it reached the Great Australian Bight while retaining tropical characteristics despite its low-latitude. Early on 22 May, the system lost its identity south of Australia as an extratropical cyclone.〔 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 Herbie」の詳細全文を読む スポンサード リンク
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