The Weather of February 2017

    February 2017 was brighter than usual, with the duration of sunshine in the month more than 40 percent above normal. The month was also relatively mild with a mean temperature of 17.0 degrees, 0.2 degree above the normal of 16.8 degrees. The monthly total rainfall was 19.9 millimetres, less than half of the normal of 54.4 millimetres. The accumulated rainfall of 27.7 millimetres in the first two months of the year was about 65 percent below the normal of 78.9 millimetres for the same period.

    The month had a mild start with sunny periods on the first day. A freshening easterly airstream brought cloudier conditions and slightly cooler weather over the next couple of days. With the northeast monsoon moderating and humid maritime air moving in towards the coast of Guangdong, the weather was a mixture of sunshine, haze, mist and some rain patches on 4 and 5 February. Easterly winds strengthened on 6 February and once again brought cloudier and slightly cooler weather to Hong Kong over the next couple of days.

    With a cold front moving across the coastal areas of Guangdong on the night of 8 February, local winds strengthened from the north and temperatures fell significantly overnight. Under the influence of an intense winter monsoon following the passage of the cold front, the weather became cold and dry in the next three days. After a chilly morning on 11 February, the lingering clouds were finally cleared away and a spell of sunny weather lasted for more than a week till 18 February. With plenty of sunshine and the northeast monsoon subsiding, the weather became rather warm on 16 – 18 February as daytime temperatures climbed to the mid-twenties.

    Affected by a moist maritime airstream, the weather turned generally cloudy with a few rain patches and relatively low visibility on 19 February. Warm conditions returned the next day as the clouds thinned out and temperatures at the Hong Kong Observatory rose to a maximum of 25.5 degrees, the highest of the month. The maritime airstream also brought foggy weather to Hong Kong on the morning of 21 February with visibility at Waglan Island falling below 200 metres. With the setting in of a fresh to strong easterly airstream that day, the weather turned cooler and cloudy with rain patches, and a few thunderstorms also affected Hong Kong on the morning of 22 February.

    Following the passage of a cold front early on 23 February, an intense northeast monsoon brought overcast sky, light rain patches and cold mornings that persisted for the next three days. Temperatures at the Hong Kong Observatory fell to a minimum of 10.6 degrees on the morning of 26 February, the lowest of the month. Under the influence of a dry continental airstream, there were sunny periods with cool mornings towards the end of the month.