A hot and rainy June
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Under the influence of an active southwest monsoon, the weather was mainly cloudy and showery on the first two days of the month. The weather turned brighter on June 3. With the winds subsiding and more sunshine, the weather became very hot on June 5 to 7. Despite the fine conditions, a lingering trough over the inland areas of Guangdong led to some significant development of showery activities along the coast that affected the territory on June 6 and 7. Generally fine weather persisted till June 11, with temperature at the Hong Kong Observatory rising to a maximum of 34.1 degrees that day, the highest of the month.
Meanwhile, an area of low pressure over the South China Sea developed into a tropical storm, named Merbok, on June 11. Merbok moved across the northern part of the South China Sea on June 12 and intensified further into a severe tropical storm that night. It traversed the eastern part of Hong Kong waters and made landfall over the Dapeng Peninsula before midnight. With the approach of Merbok, local winds strengthened significantly with heavy squally showers later on June 12, necessitating the issuance of the first No. 8 Gale or Storm Signal in June since 2012. As Merbok weakened over land, its rainbands continued to affect the south China coastal region with gusty winds and heavy rain. The Hong Kong Observatory issued the Red Rainstorm Warning Signal in the morning of June 13, and recorded a temperature of 24.3 degrees that day, the lowest of the month. More than 150 millimetres of rainfall were generally recorded over the territory on June 13 and 14, with rainfall over the urban areas exceeding 250 millimetres.
Under the influence of an enhanced southwest monsoon in the wake of Merbok on June 15 and 16, and the development of a lingering trough of low pressure along the coastal areas of the Guangdong, the weather remained unstable and rainy till June 21. In particular, outbreaks of heavy rain and squally thunderstorms on June 17 brought more than 100 millimetres of rainfall to the territory, leading to the issuance of the Red Rainstorm Warning Signal again.
After the dissipation of the trough, the weather turned fine and hot on June 22. A mixture of sunshine and showers then persisted for the next five days. Despite the development of another trough over southern China, showery activities over the coastal region gradually subsided. Weather during the daytime became very hot towards the end of the month as generally fine weather prevailed over the territory.
One tropical cyclone occurred over the South China Sea and the western North Pacific in June 2017.
Details of issuance and cancellation of various warnings/signals in June are summarised in Table 1. Monthly meteorological figures and departures from normal for June are tabulated in Table 2.
Ends/Tuesday, July 4, 2017
Issued at HKT 16:54
Issued at HKT 16:54
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