Why does it rain all the year round in Hunan?
Hunan is located in the transition zone from Yunnan-Guizhou Plateau to Jiangnan hills and Nanling Mountains to Jianghan Plain. It is a horseshoe-shaped landform surrounded by mountains on three sides and open to the north. It is composed of plains, basins, hills, mountains and lakes, spanning the Yangtze River and the Pearl River, and belongs to the subtropical monsoon climate.
In Hunan, spring is warm and cold, and the weather changes dramatically. Although the temperature gradually warms up in spring, cold air from north to south can still invade Hunan frequently, resulting in a sudden drop in temperature, accompanied by strong convective weather processes such as strong winds, hail and heavy rain. After the cold air, the rain turned fine and the temperature rose quickly.
Generally speaking, there are 3-4 cold air intrusions every month from March to April, and the average daily temperature generally drops by more than 10℃, and sometimes even exceeds 15℃. There are 2-3 cold air intrusions in May, and the daily average temperature can drop by more than 7℃.
There is little rain in summer and autumn in Hunan, and there is drought almost every year, but the influence scope and severity are different. From late June to early July, the rainy season ended in most parts of Hunan except northwest Hunan, and the number of rainy days and rainfall decreased significantly.