Origin of the name "Plum Rain

Plum rain is a unique weather phenomenon in East Asia, its name originates from the ripening season of plums in the Jiangnan region of China during June and July, due to the stagnant front wandering, resulting in cloudy and rainy, long rains do not clear up and so on, the main distribution area from the Guangdong coast to the north extends to the Yangtze River Basin and the area.

Reasons for the Formation of the Plum Rain] How is the Plum Rain formed? As the northeast monsoon prevails in Taiwan in winter and the southwest monsoon prevails in summer, when the northeast monsoon gradually weakens in May and June, the southwest monsoon, which originates from the southern tropical oceans, gradually strengthens and pushes northward. At this time, cold and warm air masses of comparable strength will meet in the area between southern China and Taiwan to form a nearly stalled frontal system hovering around Taiwan due to the instability of the airflow over the frontal zone and the abundant moisture, which can easily trigger small- to medium-scale convection. Due to the instability of the airflow over the frontal zone and the abundance of moisture, small to medium scale convection will easily be triggered, resulting in continuous rainfall and localized heavy rain or downpours.

The Central Weather Bureau (CWB) defines May and June as the rainy season in Taiwan, and on average, rainfall is more likely to occur from mid-May to mid-June. This continuous rainfall is the main cause of disasters, but the rainy season does not mean that it rains every day or continuously.

The Plum Rain is not just a nuisance. About 30% of Taiwan's annual rainfall is concentrated during the Plum Rain season, and the abundant rainfall it brings is the second most important source of precipitation in Taiwan after typhoons. May and June are the rainy seasons in Taiwan, which are often characterized by sudden and intense downpours or days of torrential rains that can lead to rockfalls, landslides, mudslides, flash floods, and transportation inconveniences. During the rainy season, please pay attention to the heavy rainfall and heavy rainfall advisories issued by the Central Weather Bureau to prevent disasters caused by heavy rainfall.