AnnualReport-1927 — Page 162

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III. METEOROLOGICAL OBSERVATIONS AT THE OBSERVATORY.

Automatic records of the temperature of the air and evaporation were obtained with a Richard dry and wet bulb thermograph, and of the direction and velocity of the wind with a Beckley and a Dines-Baxendell anemograph, modified as described in the report for 1912. The amount of rain is re- corded automatically by a Nakamura pluviograph and the amount of sunshine by two Campbell-Stokes universal sunshine recorders. Eye observations of barometric pressure, temperature of the air and of evaporation and the amount of cloud are made at each hour of Hong Kong Standard time. The character and direction of the motion of the clouds are observed every three hours. Daily readings are taken of self-registering maximum and minimum thermometers.

Principal features of the Weather.-The principal features of the weather in 1927 were:-

(a) Rainfall very considerably above normal in May and considerably above normal in July and August. 6.01 inches fell from May 6 to 8 and 15.75 inches from May 17 to 24.

(b) Temperature considerably below normal in March and April and considerably above in November and December.

(c) A typhoon which passed a few miles to the South of Hong Kong in the morning of July 25, causing a moderate gale. Another typhoon which passed a few miles to the South of Gap Rock in the morning of August 20, causing a violent gale at Hong Kong.

Barometric Pressure was persistently below normal from January to August, and again in November and December. In September it was considerably above normal and in October moderately above. The mean pressure for the year at station level (109 feet above sea level) was 29.830 ins. as against 29.857 ins. in 1926 and 29.842 for the past 44 years. The highest pressure was 30.305 ins. on February 7 as against 30.384 ins. in 1926 and 30.509 ins. for the past 44 years. The lowest pressure was 28.927 ins. on July 25 as against 29.229 ins. in 1926 and 28.590 ins. for the past 44 years.

The temperature of the air was considerably below normal in March and April and considerably above in November and December. The mean temperature for the year was 71°.4 as against 71°.6 in 1926 and 71°.8 for the past 44 years.

The highest temperature was 93°.1 on August 19, as against 92°.5 in 1926 and 97°.0 for the past 44 years. The lowest temperature was 45°.9 on February 7, as against 43°.2 in 1926 and 32°.0 for the past 44 years.