Why does it rain every day in Dongguan this summer?

Because it is the rainy season, here are some information about the rainy season: 1. Meiyu In the middle and lower reaches of the Yangtze River in China, it is usually the rainy season from mid-June to early July every year. The sky has been gloomy for days, and the precipitation is continuous, sometimes big and sometimes small. Therefore, there is a popular proverb in southern China: "When the rain hits the plum blossom, there will be no sun for forty-five days". Continuous rain, high temperature and high humidity are the main characteristics of plum rain. Very different from the climate in the same latitude area, Meiyu refers to the weather and climate phenomenon that occurs in a certain area and a certain season. It is found that Eurasia is between 2N and 4N, which is controlled by subtropical high and westerly belt alternately. The west coast of the mainland is controlled by the downward flow on the east side of the subtropical south pressure in summer, with sunny weather and hot and dry climate in partly cloudy; In winter, under the influence of westerlies, warm and humid air is brought from the Atlantic Ocean, resulting in more precipitation, which makes the climate mild and rainy. That is, the subtropical Mediterranean climate is dry in summer and wet in winter. The east coast of the mainland is controlled by the west side of the subtropical high in summer, and the sinking air is dry, but it absorbs a lot of water vapor from the warm and humid sea surface, which brings abundant precipitation and produces a subtropical humid climate. Because of the strong contrast between land and sea, a unique monsoon climate is formed here, which is characterized by rainy summer and dry winter, and the rainfall is concentrated in summer, which is just the opposite of Mediterranean climate. If compared with the east coast of Britain at the same latitude, it is also very different. There will be no long-term rainy weather before and after the summer monsoon in the mid-latitude zone on the east coast of the United States, and people have never felt the feeling of long-term sultry weather, so it is difficult to appear moldy. It can be seen that the precipitation seasons are very different at the same latitude. Therefore, in the world, there are only Huangmei in the middle and lower reaches of the Yangtze River in China, starting from the area east of Yichang and 29-33 degrees north latitude, as well as in southeastern Japan and the southernmost part of the Korean Peninsula. In other words, Meiyu is a unique weather and climate phenomenon in East Asia, and it is a unique weather and climate phenomenon in the middle and lower reaches of the Yangtze River in China. 2. Rain belt Although Meiyu is a unique weather and climate in the middle and lower reaches of the Yangtze River, its appearance is not isolated, but closely linked to the north-south displacement of a large-scale rain belt. In the east of China, from mid-May to early June in the flood season, the main rain belt swings in the Nanling Mountains and the south of Nanling Mountains. In a few years, although it moved to the north of Nanling within a certain period of time, from the multi-year average of a waiting period (five days) or a ten-day period, it often remained at the south of 28N and 29N. This period is called "rainy season in the south of the Yangtze River" or "pre-flood season in South China". In the middle and late June, the main rain belt moved northward within the range of 29N-33N (that is, from Yichang in China in the west, the Yangtze River estuary in the east longitude, and then across the sea to Japan; From the south of China's two lakes basin to the south bank of Huaihe River), it is stable and less moving. At this time, the area south of Nanling is outside the rain belt, and the rainy weather is over; The middle and lower reaches of the Yangtze River bid farewell to the sunny early summer and ushered in a rainy season, with heavy rain and rainstorm appearing from time to time until early July, which is the famous rainy season in the middle and lower reaches of the Yangtze River. Beginning in mid-July, the rain belt moved northward again, reaching the area north of 33N. Stagnation and wandering in the Yellow River, Huaihe River Basin, North China, Northeast China and other places have caused heavy rainfall again and again, which are called "Huanghuai rainy season" and "North China rainy season" respectively. At this time, the plum rains in the middle and lower reaches of the Yangtze River ended and the sun hung high, entering the hot summer season. This kind of weather will last until the end of August, and then the rain belt will quickly retreat southward with the gradual activity of cold air. In less than a month, the rain belt will always retreat to the coastal areas of South China. This regular change of rain belt shows that the plum rain in the middle and lower reaches of the Yangtze River is not an isolated and local weather and climate phenomenon, but an integral part of the main rainy season activities in eastern China and a reflection of the stagnation of the main rain belt in the middle and lower reaches of the Yangtze River during its northward movement.