2nd February 2023 – (Hong Kong) With the northeast monsoon over Guangdong generally weaker than normal for most of the time in the month, despite a few cold interludes, January 2023 was overall warmer than usual in Hong Kong. The monthly mean temperature was 17.0 degrees, 0.5 degrees above the normal of 16.5 degrees. The month was also drier than usual. The monthly total rainfall was 18.2 millimetres, about 45 per cent below the normal figure of 33.2 millimetres.
Under the influence of the northeast monsoon, the weather of Hong Kong was dry with sunny intervals on the first two days of the month. Affected by a replenishment of the northeast monsoon and a band of clouds over the coast of Guangdong, the weather turned mainly cloudy and cooler with a few rain patches on 3rd January. With the thinning out of cloud band covering the coastal areas, there were sunny periods on the afternoon of 4th January. The weather became fine and mild during the day on 5th and 6th January under the moderation of the northeast monsoon.
With the setting in of a fresh to strong easterly airstream and the influence of a broad band of clouds associated with an upper-air disturbance, the weather of Hong Kong turned cloudier on 7th January. Local weather remained cloudy with a few rain patches on 8th to 12th January. Affected by a maritime airstream, the weather became mild and foggy with a few rain patches on 13th and 14th January. The visibility at Waglan Island once fell to around 100 metres on the morning of 13th January. With sunny periods during the day, the temperatures at the Observatory rose to a maximum of 24.7 degrees on 14th January, the highest of the month.
A cold front moved across the coast of Guangdong on the morning of 15th January. Locally, it was mainly cloudy with temperature falling significantly on 15th January. There were also a few rain and fog patches at first on that day. Under the influence of the northeast monsoon, it was cloudy and cold on 16th and 17th January. While it remained cold on the morning of 18th January, the weather turned generally fine and dry on 18th and 19th January under the influence of a continental airstream. Affected by an easterly airstream and a band of clouds covering the coast of Guangdong, the weather of Hong Kong was a mixture of sunny periods and a few rain patches from 20th to 22nd January. Under light wind conditions, there were sunny periods with rather low visibility in some areas on 23rd January.
Another cold front moved across the coast of Guangdong on the morning of 24th January. With winds strengthening from the north, apart from a few rain patches at first, the weather of Hong Kong became fine, dry and significantly colder on that day. Under the influence of the associated intense northeast monsoon, it was mainly cloudy with cold mornings on 25th and 26th January. With the arrival of a replenishment of the dry northeast monsoon, the weather turned generally fine and dry on 27th January. Local weather remained fine with cold mornings in the next three days. The temperatures at the Observatory fell to a minimum of 9.8 degrees on the morning of 29th January, the lowest of the month. It was also very dry during the day on 28th and 29th January. Moreover, there were frost reports in Tai Po and parts of the northeastern New Territories respectively on the mornings of 29th and 30th January. With the northeast monsoon moderating, there were sunny periods with rising temperature on the last day of the month.
There was no tropical cyclone over the South China Sea and the western North Pacific in January 2023
