THE ENVIRONMENT
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millimetres. The driest month is January with 23.4 millimetres and rainfall on only about six days.
Severe weather phenomena that can affect Hong Kong include tropical cyclones, strong winter and summer monsoon winds, monsoon troughs and thunderstorms with associated squalls that are most frequent from April to September. Waterspouts and hailstorms occur infrequently, while snow and tornadoes are rare.
Climatological data are given in Appendix 49.
The Year's Weather
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It was a warm year. The annual mean temperature of 23.3 degrees was the sixth- highest on record. It was also dry with a mean relatively humidity of 76 per cent, which ranked the fourth-lowest. The year's total rainfall was near normal and amounted to 2 249.1 millimetres, only two per cent above the normal of 2 214.3 millimetres. Seven tropical cyclones necessitated the hoisting of local Tropical Cyclone Warning Signals, as compared with the annual average figure of about six, and the No. 8 Gale or Storm Signal was hoisted once.
January 1996 was warmer and cloudier than normal. The mean temperature of 17.8 degrees was the fifth-highest for January. The month was also drier with a total rainfall of only 1.3 millimetres which was 22.1 millimetres below normal.
Cold winter monsoons dominated most of February. Daily minimum temperatures of below 10 degrees were recorded each day from February 18 to 24, the sixth-longest cold spell recorded in February. The monthly total rainfall amounted to only 27.2 millimetres, 43 per cent below normal.
March was slightly warmer than normal. The monthly total rainfall amounted to 83.1 millimetres which was 16.2 millimetres above normal. Nevertheless, the accumulated rainfall since January 1 was still 19 per cent below average.
It was cooler than normal in April and the minimum temperature of 10.9 degrees on April 3 was the third-lowest recorded for the month. Three episodes of heavy rain contributed to most of the month's rainfall of 228.7 millimetres, 67.2 millimetres above normal.
May was slightly cooler with near normal rainfall.
June was the hottest on record. The mean temperature of 28.8 degrees equalled the previous record set in 1977 and 1938. The monthly mean pressure of 1008.8 hectopascals was the third-highest for June due to the dominance of the subtropical ridge over South China. Both the monthly total rainfall and the accumulated rainfall for the year were seven per cent above normal for the same periods.
July was hot. The mean temperature of 29.2 degrees and the absolute maximum of 34.3 degrees ranked the sixth- and ninth-highest respectively on record for July. Occasional showers and thunderstorms affected the territory but the monthly rainfall of 230.3 millimetres was still 29 per cent below normal. In the second half of the month, tropical cyclones Frankie and Gloria necessitated the hoisting of the Stand By Signal No. 1.
August was cloudier than normal and there were nine days with thunderstorms. The weather was unstable from August 14 to 18 with 206.1 millimetres of rainfall. Torrential rain on August 15 caused flooding in many places. The Stand By Signal