It rains at the autumn equinox. It doesn't rain everywhere at the autumn equinox, does it?

If it rains during the autumnal equinox and solar terms, there will be a good harvest in the coming year. There are many such sayings among the people, all of which are based on many years' observation. They are catchy and easy to remember and have been passed down to this day.

The autumnal equinox is the sixteenth solar term in the twenty-four solar terms of the lunar calendar, which usually lasts from September 22nd to September 24th every year. The climate in the south began to decline from this solar term. After the autumnal equinox, the northern hemisphere has shorter days and longer nights (shorter days than nights), while the southern hemisphere has longer days and shorter nights (longer days than nights).

After the autumnal equinox, the polar night range near the North Pole and the polar sun range near the South Pole gradually expanded. According to the division of seasons in ancient China, which started with beginning of spring, Changxia, beginning of autumn and beginning of winter, the autumnal equinox is divided into 90 days in autumn and divided equally in autumn.

The autumnal equinox solar terms are influenced by the cold air mass in the north. In addition, as the sun moves south, the light intensity in the northern hemisphere weakens, the ground temperature dissipates quickly, and frost even appears prematurely in the north, while the temperature in the south is cool. When the cold air in the south meets the humid warm air in the south, it will produce rain, and then the temperature will drop sharply. As the saying goes, "an autumn rain brings a cold", but in China, there will be a strange scene of heavy snow in the northwest and continuous autumn rain in the south of the Yangtze River.