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Under the prolonged dominance of the sub-tropical ridge, Hong Kong experienced one of the hottest August since records began in 1884. The monthly mean temperature soared to 29.5 degrees, equaling the record set in 1990 and 1998 and was 1.1 degrees above normal. The month was sunnier than usual. The monthly total duration of bright sunshine was 242.0 hours, 52.3 hours higher than normal. The month was also dry with a total rainfall of 157.6 millimetres, only 35 percent of the normal figure and the accumulated rainfall since 1 January of 1102.8 millimetres suffered a deficit of 41 percent compared to the normal figure of 1873.7 millimetres for the same period.
Under the influence of a persistent anticyclone aloft, the weather in Hong Kong was sunny and very hot for first seven days of the month. The temperatures at the Hong Kong Observatory rose to a maximum of 35.0 degrees in the afternoon on 7 August, the highest of the month.
A trough of low pressure developed near the South China coast and brought thundery showers to the territory for the next two days. As the trough of low pressure became more active, there were occasional heavy rain and squally thunderstorms over the territory on 10 August. With the weakening of the trough of low pressure on 11 August, the rain eased off and there were sunny periods during the day.
Dominated by a ridge of high pressure over southern China, local weather became sunny and hot apart from a few showers from 12 to 16 August. With a temporary retreat of the ridge, there were thunderstorms in the afternoon on 17 August. As the ridge re-established over southern China, local weather became generally fine and very hot in the ensuing three days. Despite the weakening of the ridge of high pressure, the weather was generally fine apart from a few showers and isolated thunderstorms from 21 to 23 August. A trough of low pressure over southern China edged towards the coast of Guangdong on 24 August and brought showers to the territory. Under the influence of the trough of low pressure, thundery showers developed locally in the afternoon on 25 August.
Affected by a continental airstream, the weather was generally fine and very hot apart from a few isolated showers and some haze from 26 to 28 August. Meanwhile, Typhoon Namadol over the Luzon Strait headed generally northwards towards Taiwan on 28 August, crossing the southern part of the island on 29 August. It moved towards Fujian the following day while weakening into a tropical storm. Namadol subsequently made landfall over the province and weakened further on 31 August. During this period, Hong Kong remained outside the core circulation of Namadol and was under the influence of a dry west to northwesterly airstream. Local weather continued to be very hot with haze for the last three days of the month.
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