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TROPICAL CYCLONE SUMMARIES FOR 1980
In 1980 twenty-eight tropical cyclones formed over the western North Pacific and the South China Sea and fifteen of them attained typhoon intensity. Eight tropical cyclones crossed the coast of Guangdong (Kwangtung). Two tropical cyclones passed over Taiwan while another nine crossed the Philippines. Six tropical cyclones affected Vietnam but only one hit Japan. The monthly distribution of tropical cyclones is shown in Figure 1 and a brief summary of their tracks is contained in Table 1. Six-hourly positions of these tropical cyclones together with their estimated minimum central pressures and maximum surface winds are tabulated in the appendix. The monthly mean frequency of occurrence of tropical cyclones during the years 1946-1979 is given in Figure 2.
During the year there were seventeen tropical cyclones in Hong Kong's area of responsibility for tropical cyclone warnings for shipping (i.e. the area bounded by 10°N, 30°N, 105°E and 125°E) compared with an average of sixteen over the past 34 years. Eleven tropical cyclones moved into the area while six developed within it. Altogether 458 warnings for shipping were issued by the Royal Observatory in connection with these tropical cyclones, and tropical cyclone warning signals were displayed in Hong Kong during ten of them. However, only two tropical cyclones came within 100 nautical miles of Hong Kong and there was very little damage.
The total tropical cyclone rainfall during the year amounted to 627. I mm which is slightly above the annual average value of 566.9 mm and accounts for 37 per cent of the year's total rainfall of 1 710.6 mm. More than half of the rainfall was due to two tropical cyclones in July: Severe Tropical Storm Ida with 190.8 mm and Typhoon Kim with 139.2 mm.
The first tropical cyclone of the year was a tropical depression which crossed the central Philippines on 24 March and dissipated off Vietnam five days later. There were no tropical cyclones during April.
Typhoons Dom and Ellen and Severe Tropical Storm Forrest originated near the Caroline Islands on 9, 13 and 20 May respectively. Dom and Ellen both recurved but Forrest crossed north Luzon on 25 May and weakened over the Bashi Channel. Severe Tropical Storm Georgia developed over the South China Sea on 19 May and caused strong winds in Hong Kong. Georgia landed near Shantou (Swatow) on 24 May. • Severe Tropical Storm Herbert was the only tropical cyclone during June. It crossed Hainan Dao (Hainan Island) and dissipated near Hanoi on 28 June.
There were six tropical cyclones during July and tropical cyclone warning signals were hoisted for four of them.
On 2 July a tropical depression formed over the South China Sea but dissipated the next day. Severe Tropical Storm Ida passed close to Basco Island on 10 July and landed near Shantou. On 19 July a tropical storm struck Shangchuan Dao (St. John's Island) and then dissipated near Nanning in southwest China. Typhoon Joe crossed Luzon on 21 July leaving about 50 000 homeless. It passed about 190 nautical miles to the south-southwest of Hong Kong on 22 July. This was the only occasion on which gale signals were hoisted in Hong Kong in 1980. Joe later struck the Leizhou (Luichow) Peninsula and according to Chinese newspapers, the typhoon was the strongest over the region in 26 years. Typhoon Kim followed Joe's path and devastated the northern Philippines on 25 July. 12 000 houses were destroyed and 500 villages flooded. Kim landed near Shantou two days later. Typhoon Lex recurved to the southeast of Japan and became extra tropical.
There were three tropical cyclones in August. Typhoon Marge formed east of Guam and became extratropical south of the Aleutian Islands. A tropical depression crossed the Leizhou Peninsula and weakened near Hanoi.
Typhoon Norris swept past Taiwan and brought much-needed rain. It then crossed the China coast near Xiamen (Amoy).
Seven tropical cyclones developed over the western North Pacific and the South China Sea in September but none of them came very close to Hong Kong. The earliest one, a tropical depression, landed in Vietnam. Typhoon Orchid passed over Kyushu on 11 September causing damage in 23 of the 47 Japanese provinces and later affected South Korea. Typhoon Ruth struck Hainan Dao on 15 September and reached Vietnam the next day. Ruth was said to be the worst typhoon to hit Thanh Hoa province in 30 years. At least 106 people were killed or missing and about 500 000 made homeless. Typhoon Percy crossed the southern tip of Taiwan devastating banana and sugar cane plantations. Three other tropical cyclones moved away into the Pacific.
Of the five tropical cyclones developing in October, only Tropical Storm Cary threatened Hong Kong. It dissipated over the Vietnam coast on 2 November. Typhoon Wynne battered the Ryukyu Islands, and after absorbing Tropical Storm Alex, Wynne became extratropical off Japan. Typhoon Betty formed near the Caroline Islands on 29 October and struck Luzon on 5 November inflicting an estimated loss of US$54 million in property and crops. Typhoon Dinah recurved and become extratropical on 26 November.
Tropical Storm Ed was the only tropical cyclone that developed during December. It dissipated east of the Philippines.