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THE ENVIRONMENT
from April to September. Waterspouts, hailstorms and snow occur infrequently and tornadoes are rare.
The Year's Weather
The year was marked by the lowest amount of sunshine since record keeping began in 1884. Bright sunshine totalled only 1 701.9 hours, compared with an annual average of 2011.6 hours. The month of July was an exception: it was the sunniest month ever. Total rainfall recorded at the Royal Observatory during the year was 2017 mm, which was nine per cent below normal. The annual mean temperature of 22.5°C was close to the normal figure of 22.8°C. No severe damage was caused by tropical cyclones in 1984.
The first half of January was generally fine and sunny but the weather during the rest of the month was cloudy with occasional light rain. However, rainfall totalled only 3.5 mm, or 13 per cent of the normal amount. January was also drier and cooler than usual with eight days having minimum temperatures below 10°C. The lowest temperature of the month, 8.0°C, was recorded on January 22. The same day, minimum temperatures of -0.5°C and 0.9°C were registered at Tai Mo Shan and Tate's Cairn respectively. The cold weather caused the death of a 72-year-old man in To Kwa Wan.
February was extremely dry with rainfall, at 2.7 mm, being only six per cent of the normal amount. The cumulative rainfall from November 1983 to February 1984, 13.6 mm, was the lowest on record for any four consecutive months. The month was also cloudier and cooler than usual with the lowest temperature of 7.0°C being recorded on February 7. Minimum temperatures of -2.0°C and 0°C were also recorded that day at Tai Mo Shan and Tate's Cairn respectively. Widespread fog on February 22 and 23 resulted in the diversion of nine inbound aircraft and the disruption of ferry services.
March was cloudy. The mean cloudiness of 91 per cent was 15 per cent above average while the total sunshine, 52.4 hours, was only 52 per cent of the normal figure. Rainfall totalled 13.6 mm, only about a quarter of the average amount. The month was also characterised by frequent fog. At Waglan Island, fog was reported every day from March 12 to March 20, equalling the record for consecutive days of fog set in March 1980. The fog caused 21 aircraft to be diverted and there were several accidents at sea. On March 13, a jetfoil ran aground shortly after leaving Macau for Hong Kong. Later that day, a fishing boat sank after being in collision with a 2 686-ton Chinese cargo ship about three kilometres southeast of Nam Kok Tsui. The next day, a Macau-bound jetcat ferry and a launch collided off Tsing Yi Island. On March 15, a Marine Police launch and a cargo vessel were in collision off Cheung Chau. The first thunderstorm of the year occurred on March 19.
April was extremely cloudy. The mean amount of cloud, 94 per cent, equalled the record set in April 1934. Only 38.6 hours of sunshine were recorded, the lowest figure ever for the month. Rain was recorded on 20 days, the highest number for the month since 1926 and the second highest since 1906. Fog occurred occasionally in the early part of April, and there were two serious accidents at sea. On April 1, a 10 000-ton Panamanian cargo vessel ran aground at Lei Yue Mun. On April 5, a 9 292-ton Panamanian container ship and a 3 503-ton Korean vessel were in collision about five kilometres southeast of Waglan Island. The larger vessel sank soon afterwards. Thunderstorms and heavy showers were reported occasionally from mid-April, bringing total rainfall for the month to 215 mm, which was 54 per cent above average. The heaviest downpour was on April 17, causing two fatalities: a 27-year-old woman was swept away by a torrent in Tuen Mun and a 59-year-old man was buried by a mudslip at a construction site in Tai Po.