Is September autumn or summer?

Autumn is a transitional season from summer to winter. The lunar calendar is from beginning of autumn to beginning of winter from July to September, the solar calendar is from 9: 00 to165438+1October, and the astronomical cycle is from the autumnal equinox to the winter solstice.

The phenological criteria studied by meteorologists are: after the summer heat, it is considered as autumn when the average temperature for five days is stable below 22 degrees, and it ends when it is below 10 degrees.

As can be seen from the date distribution map of beginning of autumn in China, Northeast China is the earliest place in beginning of autumn in eastern China. In autumn, the cold air in the north is constantly invading, but its power is not very strong. Autumn weather often forms in northern China, and continuous autumn rain often appears in West China.

The main meteorological disasters in autumn are: autumn rain in West China, cold dew wind in the south, frost and chilling injury at low temperature. Generally speaking, in autumn, the solar altitude angle decreases and the temperature decreases; The autumn wind is cool, the summer heat is gone, the fruits are covered with branches, and the fields are golden.

solar term

August 7-9 is the beginning of autumn Festival.

August 22-24 in summer.

Celebrate the Millennium from September 7 to 9.

The autumnal equinox is on September 22-24.

Cold dew 65438+1October 8-9 Festival

The first frost is 65438+1October 23-24.