THE ENVIRONMENT
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August was wetter and cloudier than usual. The total rainfall was 21 per cent above normal. Most of the showers and thunderstorms occurred in the second half of the month, with more than half of the month's total rainfall being recorded in the last week.
September was cooler, cloudier and more humid than usual. The mean maximum temperature of 29.0°C was 1.5°C below normal and the ninth lowest on record for September. Typhoon Tess came close to Hong Kong on September 6, causing gale force winds and frequent squally heavy showers. During the approach of Tess, two people were killed and there were landslips and floods in various parts of Hong Kong. Flooding was more serious in the northwestern part of the New Territories. Among the worst-affected areas were Kam Tin, Pat Heung, Ngau Tam Mei, Sheung Shui and Tai Po. Landslips occurred in Sheung Wan, Shau Kei Wan, Kwun Tong, Sai Kung, Sha Tin and Tsuen Wan. Ferry services were suspended. At the airport, two aircraft were diverted from Hong Kong, 10 flights were cancelled and 50 delayed. Tropical Storm Val entered the northern part of the South China Sea on September 17 but dissipated the following day about 440 kilometres east-southeast of Hong Kong without causing any damage to the territory. A waterspout was sighted south of Wong Ma Kok, Stanley Peninsula, at 9.35 a.m. on September 21.
October was warmer and drier than usual. The month's mean temperature of 25.8°C was the seventh highest on record for October. The total rainfall for the month amounted to only 56.1 mm, which was 54 per cent below the normal value of 121.2 mm. Typhoon Dot entered the South China Sea on October 19 after crossing Luzon. Under the combined effects of Dot and the winter monsoon, strong northerly winds were experienced offshore and in exposed places in the following two days.
November was again warmer than usual. The month's mean temperature of 22.4°C was the sixth highest on record while the mean minimum temperature of 20.6°C was the third highest on record for November.
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December was slightly cooler than usual. The month's mean maximum temperature of 19.7°C was 1.1°C below normal. A prolonged spell of dry and cold weather occurred around the middle of the month. The relative humidity recorded at the Royal Observatory fell to 22 per cent on December 15, when numerous hill fires were reported. Temperatures fell to 0°C at Ta Kwu Ling on December 17 and hoar frost was reported at Ta Kwu Ling, Sheung Shui and Fanling.
The Royal Observatory
The Royal Observatory was established in 1883 mainly to provide scientific information for the safe navigation of ships. In the ensuing century, the observatory has evolved in line with the changing needs of the community. By 1985, its work covered a wide range of scientific disciplines.
Operations and Services
The department's most important function is the provision of weather forecasts and tropical cyclone warnings for the public, shipping and aviation. The Central Forecasting Office issues local weather forecasts and warnings of hazardous weather conditions to the press, radio and television broadcasting stations, and government departments. Whenever Hong Kong is threatened by tropical cyclones, frequent warnings with advice on necessary precautions are issued and widely disseminated. Other warnings cover thunderstorms, flooding, landslips, storm surge, fire danger, strong monsoons and frost. Regular weather bulletins are issued to ships at sea, fishermen in coastal waters and yachtsmen. Specialised forecasts are prepared on request for offshore operations in the China Seas.