Why does it rain in Tomb-Sweeping Day almost every year? Is it a coincidence?

105 The first day after winter is Qi Tomb-Sweeping Day. Tomb-Sweeping Day gas * * * has 15 days. As it is Tomb-Sweeping Day, the time is after the vernal equinox. At this time, winter has gone, spring is full, the weather is sunny, the fields are bright and clean, and the vitality of nature is everywhere. It is an appropriate word to call this period "Qingming".

"There are many rains during the Qingming Festival" is a portrayal of the spring rain in the south of the Yangtze River by Du Mu, a famous poet in the Tang Dynasty. But in some areas, this is not the case. Especially in the western part of South China, it is often in the spring drought period, and the rainfall in early April is generally only 10 to 20 mm, which is less than half of that in the south of the Yangtze River. Although there are many spring rains in eastern South China, the rainfall in early April is generally only 20 to 40 mm, so natural precipitation is not enough for agricultural production, so it must be replenished by storing water years ago. In addition, May-June is the month with the most hail in a year, so the prevention of hail disaster should be strengthened.