Why is there so much rain in spring?

Let me explain it from astronomical geography.

From the winter solstice, the direct point of the sun moves from the Tropic of Cancer to the Tropic of Cancer, that is, the daytime sunshine time in the northern hemisphere increases, and the sunshine and temperature rise again. After that, China began to enter the solar terms of fright, rain and Qingming.

During the rainy season, due to the rising temperature in the Pacific Ocean, the warm air flow began to move to the northern hemisphere under the action of the earth's rotation, especially in China, which is adjacent to the Pacific Ocean in the east, and naturally moved northward from the eastern coast of China. However, because the cold air flow in the north (Siberia) is still very strong, the two air flows are evenly matched and move back and forth along the Yangtze River and Huaihe River in China, resulting in an increase in rain in the Jianghuai area.

In summer, the warm air flow in the Pacific Ocean is strengthened, the cold air in the north is weakened, and China begins to enter the summer drought season again.