How many days is Huangmeitian?

The start date of plum rains every year is called "entering plum" or "main plum", and the end date is called "leaving plum" or "breaking plum". According to climate statistics, the rainy season begins in the first half of June and ends in early July. In the rainy season, sometimes the rainfall process is interrupted for several days, and there will be two or more rainy days. There are two rainy days, commonly known as "Ermei". On average, the rainy season began in June 17 and ended in July 10, lasting for 24 days. However, in each year, the time of entering and leaving the plum blossom is slightly different, and the length of the plum blossom period is not exactly the same. It is found that there is a certain correspondence between the time of plum blossom entry and the duration and quantity of plum blossom, that is, in the early years of plum blossom, the duration of plum blossom is long and the quantity of plum blossom is large; On the contrary, in the years when the plum rains are late, the duration of the plum rains is short and the amount of the plum rains is small. Therefore, the year when plum blossoms are too early or too late is often a year of abnormal precipitation, either waterlogging or drought.