3 March 2020

February 2020 was much warmer than usual. The monthly mean maximum temperature was 21.4 degrees, 2.5 degrees above the normal figure of 18.9 degrees and the sixth highest on record for February. The monthly mean temperature of 18.5 degrees and mean minimum temperature of 16.6 degrees were respectively 1.7 degrees and 1.6 degrees above their corresponding normal figures. Both were one of the eighth highest on record for February. Moreover, the winter from December 2019 to February 2020 was exceptionally warm in Hong Kong. The mean maximum temperature of 21.5 degrees was the highest on record for the same period. The mean temperature of 18.7 degrees and mean minimum temperature of 16.8 degrees were both the second highest on record for the same period. February 2020 was also wetter than normal with the monthly rainfall of 79.8 millimetres, about 47 percent above the normal of 54.4 millimetres. The accumulated rainfall recorded in the first two months of the year was 94.6 millimetres, about 20 percent above the normal figure of 79.1 millimetres for the same period.

Under the influence of the northeast monsoon, it was cool in the morning with sunny periods during the day on 1 February. Affected by the cloud band spreading over southern China, local weather turned cloudier with rain patches on 2 – 4 February. With the strengthening of an easterly airstream on 5 February and the subsequent replenishment of the northeast monsoon on 7 February, mainly cloudy weather with rain patches and cool mornings persisted during 5 – 11 February. The northeast monsoon affecting southern China was gradually replaced by a maritime airstream on 12 February and local weather became warm with sunny periods and coastal mist. The visibility at Chek Lap Kok once fell to around 1000 metres on that day.

Affected by an upper-air disturbance, the weather of Hong Kong turned cloudy with thundery showers on 13 – 14 February. The showers were particularly heavy on the morning of 13 February which necessitated the issuance of the first Amber Rainstorm Warning in the year. This was also the second earliest Amber Rainstorm Warning since the rainstorm warning system commenced operation in 1992. More than 30 millimetres of rainfall were recorded over Hong Kong Island, Kowloon, Lantau Island and Sai Kung. Under the influence of a humid maritime airstream, it was cloudy and foggy in Hong Kong on 15 February with the visibility at Waglan Island falling below 200 metres.

A cold front moved across the coast of Guangdong on the night of 15 February. Locally, it was mainly cloudy with occasional rain and became appreciably colder on 16 February. The associated intense but dry winter monsoon brought generally fine weather to the territory with cold mornings on 17 – 18 February. Under clear sky, the temperatures at the Hong Kong Observatory fell to a minimum of 10.3 degrees on the morning of 17 February, the lowest of the month.

The dry northeast monsoon continued to bring generally fine weather to Hong Kong during 19 – 23 February. With the moderation of the northeast monsoon, local weather became mainly cloudy with sunny intervals during the day on 24 February. Under the influence of a maritime airstream, it became warm with sunny periods on 25 February. With plenty of sunshine on 26 February, temperatures at the Hong Kong Observatory rose to the month’s highest of 28.1 degrees in the afternoon, the second highest on record for February. Under the influence of a fresh to strong easterly airstream, the weather of Hong Kong became cloudier and slightly cooler on 27 February. With the easterlies moderating and gradually replacing by a maritime airstream, it became warmer with sunny periods in Hong Kong on 28 – 29 February.

There was no tropical cyclone over the South China Sea and the western North Pacific in February 2020.

Details of issuance and cancellation of various warnings/signals in the month are summarized in Tables 1.1 to 1.6.  Monthly meteorological figures and departures from normal for February are tabulated in Table 2.