ENG-1967 — Page 316

GEOGRAPHY AND CLIMATE

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several parts of the Colony. The sky became so dark that cars had to use their headlights at 3 p.m. Hail is rare in Hong Kong and the last authenticated case on record was more than 27 years ago on March 4, 1940.

Another event of note was typhoon Violet, the first storm to enter the South China Sea in April since 1940. Violet formed near the Caroline Islands on the first, moved steadily west-north-west, but recurved just to the east of Pratas Island on the ninth and did not affect the Colony.

May was warm and very dry. Although several troughs of low pressure formed over central China and moved southwards into the South China Sea, they did not bring any appreciable rain to the Colony and the rainfall recorded was the second lowest for the month.

Several records were broken in June and July. The mean relative humidity for June was the lowest on record for the month, while the mean temperature for July was the highest ever recorded at the Royal Observatory.

In June, only one tropical cyclone came close enough to Hong Kong to necessitate the hoisting of local storm signals. Severe tropical storm Anita formed over the Pacific to the east of the Philippines on the 26th and passed about 140 miles east-north-east of the Colony four days later. Anita brought more than two inches of rain to Hong Kong, but did not cause gales or strong winds.

July was exceptionally dry and hot as all the tropical cyclones which developed over the Pacific recurved towards the north-east before entering the South China Sea. The rainfall during the month was largely due to an intense upper-air disturbance which brought thunderstorms and heavy rain on the 13th and 14th. During these two days, a total of 126.0 mm (4.96 inches) of rain was recorded at the Royal Observatory but more than 10 inches of rain fell over the Plover Cove and Tai Lam Chung catchments. On the 29th, tropical storm Fran formed over the South China Sea about 450 miles south-south-east of Hong Kong. Fran moved west-north-west and then north-west and local storm signals were hoisted twice, on July 30 and again on August 2.