THE ENVIRONMENT
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On February 1, the Royal Observatory recorded a minimum temperature of 6.1°C which was the lowest in 1979. The minimum temperatures at Tate's Cairn and Tai Mo Shan were 0.1°C and ---2.4°C, respectively. Temperatures began to rise the next day and the month as a whole was the second warmest February since 1884. The month's mean temperature was 18.9°C which is 3°C higher than normal. The warmest February was in 1973 with a mean temperature of 19.2°C. Although there was very little rain, the month was cloudier and less sunny than normal.
March was a wet month. There were only six days without rain at the Royal Observatory; the month's total rainfall was 71.9 mm, that is, 22.6 mm above normal. The month was also slightly warmer and more humid than usual. Fourteen aircraft were diverted due to fog on March 13. The strong monsoon signal was hoisted on three occasions while the yellow fire danger warning was only issued on two days.
April was much wetter than usual. The month's total rainfall amounted to 234.5 mm which is 73 per cent above average. Although the mean temperature for April was slightly below normal, the temperature on April 26 reached a maximum of 32.4°C – the highest April temperature since April 27, 1956. Four short periods of strong winds were experienced during the month and the strong monsoon signal was hoisted. The arrival of an intense cold front on April 2 brought heavy squally showers and thunderstorms, and flooding was reported in parts of Hong Kong. Widespread fog on April 7 and 8 affected the ferries between Hong Kong, Macau and Guangzhou (Canton).
May was cloudier and less sunny than usual. The month's total rainfall amounted to 311.6 mm which is eight per cent above average. More than half of this amount fell between May 13 and 15 when a trough of low pressure was near Hong Kong. Flooding was reported in many places and several minor landslips occurred.
Conditions in June were quite normal except that rainfall was below average. The wettest period was between June 7 and 11; on June 11 the rainfall amounted to 113.6 mm. The heavy rain resulted in several landslips and approximately 200 people had to be evacuated. July was sunnier and hotter than usual. On July 5, temperatures rose to a maximum of 33.8°C which was the highest in 1979. A long spell of fine and hot weather was experienced from July 7 to 28 when daily mean temperatures exceeded 29°C every day. The month's rainfall was slightly above average with most of the rain falling on the last three days of the month. A total of four tropical cyclones developed over the western North Pacific and the South China Sea during July, and for two of them tropical cyclone warning signals were hoisted in Hong Kong. Typhoon Ellis passed about 100 nautical miles to the south- southwest of Hong Kong around midnight on July 5. It resulted in a short period of strong easterly winds and some showers in Hong Kong. Severe Tropical Storm Gordon was centred near Shantou (Swatow) early on July 29, and it weakened as it moved westwards across southern Guangdong (Kwangtung). Gordon was nearest to Hong Kong around 2 am on July 29 when it was about 40 nautical miles to the north. Although there were only a few hours of strong winds offshore, rainfall was very heavy. Many places in the New Terri- tories were flooded and some minor landslips occurred.
Typhoon Hope was the most significant weather development during August. The typhoon brought hurricane-force winds and torrential rain as it passed across the New Territories on August 2. Hope caused 12 deaths, injured 260 people and made several hundred people homeless. A number of vessels went adrift in the harbour and traffic came to a standstill. Widespread flooding occurred in the New Territories and many vegetable crops, flowers and fruit trees were destroyed or severely damaged. The passage of Hope set two records. The minimum instantaneous mean sea-level pressure of 961.6 millibars recorded on August 2 at the Royal Observatory is the lowest on record for August. The