TAIPEI (Taiwan News) — Taiwan’s Central Weather Administration said this year’s plum rain season will experience higher average temperatures and less rainfall.

CWA Weather Forecast Center Director Chen Yi-liang (陳怡良) said Taiwan’s plum rains typically occur between May and June. The rains are caused by the sudden interaction between cold and warm air masses, causing short-term heavy rainfall and rainstorms, per CNA.

Data shows that central and southern mountainous areas experience significant rainfall during the plum rain season. Typically, the plum rain season begins in central areas before affecting the north, with the first plum rains in early May.

Meanwhile, in the south, plum rains typically begin in mid-to-late May. The period when significant rainfall occurs is usually the latter half of May to the first half of June.

Chen said current forecasts indicate the plum rain fronts are likely to occur in mid-to-late May, depending on the tropical depression system in the sea east of the Philippines. 

Chen said that rainfall data during the plum rain season from 1951 to the present indicates that the highest amount of rainfall was 891 mm in 2012 and the lowest was 193.4 mm in 1980. 

In recent years, although the total rainfall in the plum rain season has not increased or decreased significantly, rainfall has become more concentrated, and the frequency of short-term heavy rainfall has increased.

According to Chen, the CWA predicts normal temperatures in May, with June and July being higher this year. As for rainfall, May is expected to be normal, while June and July are expected to be below normal.

Chen reminded the public that the plum rain season marks the beginning of Taiwan's flood season. Plum rain fronts are often accompanied by thunder and lightning, and even hail or tornadoes.