Agreement No. CE 45/2008 (CE) Liantang/Heung Yuen Wai Boundary Control Point and Associated Works 10th Quarterly Environmental Monitoring and Audit Summary Report –
Weather Condition Extracted from HKO
The weather of November 2015
November 2015 emerged as the warmest November in Hong Kong since records began in 1884 with a record-breaking mean temperature of 24.0 degrees, 2.2 degrees above the November normal of 21.8 degrees. The anomalously warm weather was mainly attributed to the relatively high sea surface temperatures over the northern part of the South China Sea and the rather weak advection of cold air from the north despite the prevailing northeast monsoon. The month was also drier than usual with only 22.8 millimetres of rainfall, a deficit of about 39 percent as compared to the normal figure of 37.6 millimetres. The accumulated rainfall of 1810.2 millimetres since 1 January was about 24 percent below the normal figure of 2371.7 millimetres for the same period.
With a relatively humid air mass affecting the territory for most part of the month, the weather of December 2015 was gloomier and wetter than usual. The total duration of sunshine recorded in the month was 75.9 hours, only about 44 percent of the normal figure of 172.2 hours. Two rainy episodes on 5 and 9 December mostly contributed to the monthly rainfall of 64.3 millimetres, more than double the normal figure of 26.8 millimetres. However, the annual rainfall of 1874.5 millimetres was still about 22 percent below the normal of 2398.5 millimetres. December 2015 was also warmer than usual with a monthly mean temperature of 18.6 degrees,
0.7 degrees above the normal figure of 17.9 degrees.
January 2016 was characterized by an intense cold surge in the latter part of the month and exceptionally high monthly rainfall. The unseasonably warm weather in the first three weeks of the month was totally offset by the freezing temperatures during the 3-day period of 23 - 25 January. The mean sea level pressure of 1037.7 hectopascals on 24 January was the highest ever recorded at the Observatory. Yet the monthly averaged temperature of 16.0 degrees turned out to be deceptively unremarkable, only 0.3 degree below normal. With upper-air disturbances repeatedly affecting the south China coastal areas and bringing outbreaks of heavy rain, the Observatory recorded an all-time high monthly rainfall of 266.9 millimetres, more than ten times the January normal of 24.7 millimetres and easily breaking the previous record of 214.3 millimetres set way back in January 1887. The heavy rain on 5 January also broke the hourly rainfall record for January.
Remark: The meteorological data during the Reporting Period is presented in the relevant monthly EM&A report.
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