A rainy August
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After skirting past the north coast of Luzon, Nida intensified from a severe tropical storm to a typhoon and headed straight for the coast of Guangdong on the first day of the month. Under the influence of the outer rainbands of Nida, local weather was showery on August 1 with strengthening winds at night. Southerly gales swept in over the territory as Nida made landfall near Dapang Peninsula and moved across Shenzhen to the north of Hong Kong on the morning of August 2. With Nida weakening and moving away, local winds moderated gradually during the day. However, the weather remained overcast with heavy squally showers. More than 100 millimetres of rainfall was recorded over the territory that day, with rainfall exceeding 200 millimetres in some parts of Lantau Island. The rainy conditions continued over the next two days, with some heavy showers affecting Lantau Island and Tai Po.
With an area of high pressure developing over the southeastern part of China, the sun broke through on August 5, and the weather remained generally fine and very hot over the next three days. As a broad area of low pressure extended from the western North Pacific all the way into the northern part of the South China Sea, the weather over the coastal areas of Guangdong turned unsettled. Heat showers and intense thunderstorms around noon on August 9 brought more than 4 000 cloud-to-ground lightning stokes to Hong Kong. Cloudy and showery conditions persisted over the next seven days, and even for a rather sunny day on August 13, there were still some heavy showers affecting the western part of the territory that day. Meanwhile, several weak depressions hovered over the south China coastal waters, and one of the depressions developed into tropical storm Dianmu off the coast of western Guangdong, bringing windy conditions and squally showers to Hong Kong on August 17 and 18.
With Dianmu moving away towards northern Vietnam, local weather was a mixture of sunny periods, showers and isolated thunderstorms from August 19 to 21. The lowest temperature of the month of 24.5 degrees was recorded at the Hong Kong Observatory in the early hours of August 21, as intense thundery showers swept across the territory. Meanwhile, three tropical cyclones developed successively over the western North Pacific. Among them, severe typhoon Lionrock lingered for days over the sea areas east of the Ryukyu Islands. Affected by the sunny weather and light wind conditions in southern China, a spell of fine and very hot weather lasted for six days in Hong Kong from August 22 to 27. Temperatures at the Observatory rose to 34.4 degrees on August 25, the highest of the month.
The weather turned cloudier as showery conditions affected Hong Kong on the morning of August 28. Even though the showers eased off the next day, the skies remained cloudy as an intensifying anticyclone over China brought drier continental air to the coastal areas of Guangdong. Despite some sunny periods, mainly cloudy conditions with some showers persisted towards the end of the month.
Eight tropical cyclones occurred over the South China Sea and the western North Pacific in the month.
Details of the issuance and cancellation of various warnings/signals in the month are summarised in Table 1. Monthly meteorological figures and departures from normal for August are tabulated in Table 2.
Ends/Friday, September 2, 2016
Issued at HKT 17:22
Issued at HKT 17:22
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