September hotter than usual, reports weather watchdog

The Hong Kong Observatory (HKO) reported today that September was significantly hotter than usual, primarily due to a weaker northeast monsoon over southern China.

The monthly mean temperature reached 29.2 degrees Celsius, with the mean maximum temperature at 32 degrees Celsius, and the mean minimum temperature at 26.8 degrees Celsius. These figures represent the third highest, fourth highest, and seventh highest records for September, respectively.

Additionally, the month experienced more cloud cover and precipitation due to a stronger than normal troughing flow in the lower atmosphere over the coast of southern China and the northern part of the South China Sea.

The total rainfall for September was 520.9 mm, which is approximately 62 percent above average. However, the accumulated rainfall for the first nine months of the year totaled 2104.3 mm, about 6 percent below the norm for the same period.

Weather conditions were generally fine and very hot from September 17 to 19. On September 17, temperatures soared to a maximum of 35.7 degrees Celsius, marking the highest temperature of the month and setting a record for the hottest Mid-Autumn Festival ever recorded.

On the morning of September 23, influenced by the rain and the northeast monsoon, temperatures dropped to a monthly low of 23.4 degrees Celsius.

Furthermore, a waterspout was reported over the sea area off Hung Hom on September 28, marking the first occurrence in Victoria Harbour since records began in 1959, according to the HKO.