THE ENVIRONMENT
372
Sunnier and warmer weather was observed in March and the total sunshine duration amounted to 129.3 hours, 32.9 hours more than normal. As a result, the monthly mean temperature reached 20.1 degrees, the seventh-highest for March.
Cloudy conditions prevailed for most of April. The total bright sunshine duration was only 73.6 hours, the tenth-lowest April record. The month was also characterised by misty weather.
The weather in May was typical of the season in terms of precipitation. Heavy rain occurred on May 8, necessitating the issuance of the first Rainstorm Red Warning and Landslip Warning in the year.
Active troughs of low pressure brought a total rainfall of 783.6 millimetres in June making it the seventh-wettest June on record. There were four days with rainfall exceeding 100 millimetres recorded at the Observatory.
Exceptionally heavy rain associated with low pressure troughs continued in July. The month's total rainfall of 746.0 millimetres made it the fourth-highest for the month of July and the accumulated rainfall since January 1 of 2 154.7 millimetres was 64 per cent above normal. A Rainstorm Black Warning was issued on July 1 and Rainstorm Red Warnings were required on the first three days of the month. Landslip and Flood Warnings were also issued on two and eight occasions respectively. Furthermore, the month's total bright sunshine duration of 125.1 hours was the lowest on record. Tropical Cyclones came unusually late. The first Tropical Cyclone Warning Signal of the year was hoisted on the last day of the month due to the approach of Typhoon Victor. It was the latest first tropical cyclone on record.
The approach of Typhoon Victor in the late afternoon on August 2 necessitated the hoisting of the Increasing Gale or Storm Signal No. 9, the highest tropical cyclone warning signal since Typhoon Ellen in 1983. Victor then weakened into a Severe Tropical Storm, but it still brought cyclonic, storm-force winds before it made landfall over the western part of Hong Kong that evening. During the passage of Victor, a man was drowned near Stanley as he tried to rescue two people swept away by high seas. About 60 people were injured in other storm-related incidents. Torrential rain and thunderstorms caused three reported cases of landslips and 20 of flooding. In late August, Typhoon Zita brought more heavy rain to Hong Kong. A total of 829.0 millimetres of rainfall was recorded, making this August the fourth-wettest on record.
September was cooler than normal and the mean temperature of 26.4 degrees was the eighth-lowest for the month. With no tropical cyclones in Hong Kong's vicinity, the monthly mean pressure reached 1 012.1 hetopascals, the highest on record for September.
Rainfall in October amounted to only 112.8 millimetres or 32 millimetres below average. However, the accumulated rainfall since January 1 of 3 329.4 millimetres was 55 per cent above the normal figure, surpassing the previous record maximum annual rainfall of 3 247.5 millimetres set in 1982.
A weak north-east monsoon coupled with an unseasonal southerly airstream gave rise to the warmest November on record. The mean temperature of 23.1 degrees equalled the previous record set in 1966. The mean minimum temperature of 21.2 degrees ranked highest for November.