Why has it rained in Shanghai for two weeks?

Shanghai generally enters Mei in the middle and late June, and does not leave Mei for more than 20 days. Meiyu is divided into dry plums and wet plums. Dried plums don't rain very much, even if it does, it will soon stop, and it's sultry. Wet plums keep raining and the temperature is not high. In the middle and lower reaches of the Yangtze River in China, the rainy season usually lasts from mid-June to early July every year. In the past few days, the sky has been gloomy and the precipitation has been constant, sometimes big and sometimes small. Therefore, there is a popular proverb in southern China: "Rain hits plum blossoms, and there is no sun for forty-five days". Continuous rain, high temperature and high humidity are the main characteristics of plum rain. According to the forecast of Shanghai Central Meteorological Observatory, this year's rainy season will end on July 13.