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HONG KONG ANNUAL REPORT
varying distances from the Colony. Gales due to typhoons occur on the average about once a year, but it is only rarely that the centre of a fully developed typhoon passes sufficiently close to Hong Kong to produce winds of hurricane force.
THE YEAR'S WEATHER
The year 1958 was drier, sunnier and slightly warmer than usual. The total rainfall for the year, 2033.6 mm. (80.06 in.), was 119.2 mm. (4.69 in.) below average while sunshine exceeded the normal by 12%.
During the first two months of the year, winter monsoon surges were frequent and the monthly mean temperatures were below normal. In March the cool monsoon conditions were interrupted by warm humid spells with extensive sea fog in the harbour and coastal areas. Unusually warm and sunny weather was experienced in April and the maximum temperature of 89.8°F recorded on the 26th was the second highest on record for the month. By the end of May Hong Kong was affected by the first tropical disturbance of the year. A tropical storm, whose centre passed about 130 miles to the south-west of the Colony, gave rise to 11 hours of gales at Waglan Island. From June onwards the temperature began to rise steadily and in July, the highest temperature of the year, 94.9°F, was reached, which is a new record for the month. August was drier than usual, but September had almost twice the normal amount of rainfall. By early October the winter monsoon began to set in, and fine and dry weather persisted until the end of the year with comparatively warm days and cool nights.
During the year six typhoons and eight less intense tropical disturbances were reported in the Hong Kong storm-warning area, but only one passed sufficiently close to cause general gales in the Colony.
GEOLOGY
Hong Kong Island and the New Territories consist of numerous rugged and irregular islands with deeply dissected peninsulas. A general picture of the area is that of an upland terrain which has been invaded by the sea.
The uplands and mountains are eroded remnants of rock formations, in which relative resistance of rock and structure