Meiyu, also known as mildew rain and Huang Meiyu, is a warm and humid air current in the Pacific Ocean brought by the southeast monsoon in June and July every year. The climate phenomenon of continuous rainy days in the middle and lower reaches of the Yangtze River in China, south-central Japan, South Korea and other places is called "Meiyu", because this is the mature period of plums in the south of the Yangtze River, and this period is called Meiyu season.

Academics believe that the East Asian summer monsoon began with the onset of the South China Sea summer monsoon (in late May on average), which belongs to the category of tropical southwest monsoon, and the South China Sea summer monsoon gradually strengthened and moved northward. During the Meiyu period, it was carried northward to the middle and lower reaches of the Yangtze River, and merged with the subtropical southwest monsoon on the northwest side of the subtropical high, cold air and wind speed to form the Meiyu belt.

Introduction of early spring plum rain

In some years, the rainy season starts very early and suddenly comes at the end of May and the beginning of June. Meteorologically, the plum rain that began before "Mangzi" is generally called "early plum rain". The early Meiyu will bring some abnormal phenomena, for example, because in the atmosphere near the ground, the cold air from north to south is still very frequent in the early Meiyu.

So after the rainy day, the temperature is still relatively low, and there is even a chilly feeling. The agricultural proverb says, "Eat Dragon Boat Festival brown, freeze it three times", which means there is no obvious damp phenomenon. Farmers in some areas in the middle and lower reaches of the Yangtze River refer to Huang Meiyu, where the temperature is relatively low, as "cold water Huangmei".

Refer to the above content: Baidu Encyclopedia-Meiyu Season