The Weather of November 1999

    November was warmer and drier than normal. The monthly mean temperature of 22.2 degrees was 0.8 degrees higher than normal. There were only 15.7 millimetres of rainfall in the month, less than half of the normal. However, the accumulated rainfall of 2 096.2 millimetres since 1 January was just about four percent below normal.

    A cold front crossed the south China coastal areas on the morning of 1 November. It brought a few rain patches to the New Territories. Winds strengthened from the north and the weather was mainly cloudy. Northerly winds moderated the next day and it became sunny on 3 November under the influence of a dry northeast monsoon.

    Winds turned to easterlies gradually and cloud amount increased on 4 November. Apart from some light rain patches, it was mainly fine for the next few days and temperatures climbed up to 27.7 degrees on 8 November, the highest in the month. The weather became cloudy on 9 November. Although there were sunny periods on 10 November, it remained mainly cloudy with some light rain patches during the next couple of days.

    A rainband affected the coastal areas of Guangdong on 12 November and more than 15 millimetres of rainfall were recorded in most parts of Hong Kong. It remained cloudy with light rain the following day.

    Fine weather returned on 14 November with long sunny periods as a dry northeast monsoon reached the south China coastal areas. Although sunny weather persisted during the day, there were light rain patches during the night hours on 16 and 18 November. It became hazy on 19 and 20 November.

    Visibility improved on 21 November under the influence of a dry continental airstream. Fine and sunny weather persisted the next few days. Hazy conditions returned on 25 and 26 November.

    A cold front moved southwards across the coast of Guangdong early on 28 November. An intense northeast monsoon brought appreciably cooler weather to Hong Kong with strong northerly winds affecting the offshore areas. Temperatures dropped to 13.7 degrees on the morning of 29 November, the lowest in the month. The weather remained mainly fine and sunny till the end of the month.

    Two tropical cyclones occurred in the western North Pacific in the month.

    During the month, no aircraft was diverted due to adverse weather.