TROPICAL CYCLONES IN 2016

3.2 Severe Tropical Storm Mirinae (1603): 25 – 28 July 2016

Mirinae was the second tropical cyclone necessitating the issuance of tropical cyclone warning signal by the Hong Kong Observatory in 2016.

Mirinae formed as a tropical depression over the central part of the South China Sea about 300 km east of Xisha on the night of 25 July. Moving west-northwestwards, it intensified into a tropical storm the next morning. Mirinae made landfall over the east coast of Hainan Island on the night of 26 July and weakened slightly while crossing Hainan Island. After entering Beibu Wan, Mirinae re-organized and re-intensified the next morning, becoming a severe tropical storm on the evening of 27 July and reaching peak intensity with an estimated sustained wind of 90 km/h near its centre. Mirinae made landfall over the coast of northern Vietnam that night and weakened gradually. It finally dissipated over northern Vietnam on the evening of 28 July.

The Standby Signal No. 1 was issued at 8:40 a.m. on 26 July when Mirinae was about 500 km south-southwest of the territory. Local winds were generally moderate east to southeasterlies and occasionally fresh offshore on 26 July. Mirinae came closest to the territory around 2 p.m. that day, passing about 490 km to the south-southwest. At the Observatory Headquarters, the lowest instantaneous mean sea-level pressure of 1006.6 hPa was recorded at 4:12 p.m. on 26 July. As the departing Mirinae made landfall in the vicinity of Wanning over the eastern part of Hainan Island that night and no longer posed a threat to Hong Kong, all tropical cyclone warning signals were cancelled at 11:20 p.m. on 26 July.

Under the influence of Mirinae, a maximum sea level (above chart datum) of 2.17 m was recorded at Tsim Bei Tsui, while a maximum storm surge of 0.14 m (above astronomical tide) was recorded at Tai Miu Wan.

The outer rainbands of Mirinae brought some squally showers and thunderstorms to Hong Kong on 26 July. A few millimetres of rainfall were generally recorded over the territory that day, with rainfall amount exceeding 10 millimetres over the eastern part of Hong Kong Island.

Mirinae did not cause any significant damage in Hong Kong. According to press reports, at least one person was killed, five were injured and many houses collapsed during the passage of Mirinae in Vietnam.

Information on the maximum wind, daily rainfall and maximum sea level reached in Hong Kong during the passage of Mirinae is given in Tables 3.2.1 - 3.2.3 respectively. Figures 3.2.1 - 3.2.4 show respectively the track of Mirinae, the rainfall distribution for Hong Kong, satellite imageries and radar imageries of Mirinae.