ENG-1992 — Page 419

THE ENVIRONMENT

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the second wettest May day on record. The deluge was, however, a very localised event with Kowloon Peninsula and the northern part of Hong Kong Island bearing the brunt of the rainstorm. Four people were killed and one was reported missing in accidents brought about by the heavy rain. Most of the mudslips and floods occurred on Hong Kong Island. The worst mudslip was at Baguio Villa where 10 buildings had to be temporarily closed, affecting more than 1 500 residents. Altogether, about 200 cases of mudslips and around 300 cases of flooding were reported. Many roads on steep slopes were turned into torrents and the flood water paralysed road traffic in the urban areas.

June was the sixth consecutive month with above-normal rainfall. The monthly total of 532.8 millimetres was 42 per cent above the June normal of 376.0 millimetres. The first tropical cyclone in the year to affect Hong Kong was Typhoon Chuck which necessitated the hoisting of the No. 3 Strong Wind Signal on June 27 and 28.

July was also wetter than normal. The monthly rainfall of 358.1 millimetres was 11 per cent above the normal of 323.5 millimetres. Rain was mostly associated with active south-west monsoon early in the month and the subsequent passages of three tropical cyclones. The newly introduced Red and Black Rainstorm Warnings were issued for the first time on July 18 for the heavy rain brought by Tropical Storm Faye. On July 22, Severe Tropical Storm Gary prompted the hoisting of the No. 8 Gale or Storm Signal.

In sharp contrast to the wet anomaly which persisted from January to July, August was one of the driest and hottest Augusts on record. The monthly rainfall was only about -one-quarter of the normal of 391.4 millimetres, making it the driest August since 1962. One of the hottest days ever experienced in Hong Kong was on August 30 when the daily mean temperature was a record high 32.0 degrees. The minimum temperature of 30.0 degrees that day was the second highest for all months. the monthly relative humidity of 77 per cent and monthly rainfall of 97.7 millimetres were both the third lowest recorded in August.

September was hot and sunny with little rain. The mean daily minimum temperature of 26.8 degrees for the month was the highest on record for September. In respect of the daily mean temperature of 31.1 degrees and the minimum temperature of 29.5 degrees, September 1 was the hottest September day on record. The month's rainfall of 63.1 millimetres was only about 21 per cent of the September normal of 299.7 millimetres. It was the driest September since 1966 and the fourth driest September on record.

October was very much dominated by the north-east monsoon. Temperatures were generally below normal in a month of mainly fine and dry weather. The monthly rainfall of 30.9 millimetres was only about 21 per cent of the October normal of 144.8 millimetres.

The north-east monsoon was even more active in November. The monthly mean pressure of 1 020.1 hPa was the second highest for November. Under the influence of the continental anti-cyclone, the weather was characterised by sunny and clear skies. The relative humidity dropped to a minimum of 19 per cent on the afternoon of November 10, the lowest since 1971 for November. About 70 cases of hill fire were reported on November 9 and 10. With only three days of rain in the month, the monthly rainfall of 10.1 millimetres was only about 29 per cent of the November normal of 35.1 millimetres.

The winter monsoon moderated in December and it was one of the warmest Decembers on record. The monthly mean minimum temperature of 17.4 degrees and the monthly mean temperature of 19.2 degrees were respectively the second and third highest for December. The dry spell came to an end and the month was unusually humid with mist or haze occurring on eight days. Fog was reported inside the harbour on the morning of