Chinanews.com client, September 21. According to the Beijing Meteorological Bureau, on September 15 the daily average temperature at the Beijing Observatory dropped to 20°C, the first time it fell below 22°C since August 1, and at the same time for 5 consecutive days (9 From 16th to 20th September), the moving average temperature is lower than 22℃. According to the "Climate Seasonal Classification", September 15 is the autumn day in Beijing this year, which is 6 days later than normal.
The annual value (average from 1981 to 2010) of the time of autumn at the Beijing Representative Meteorological Observation Station (Observatory Station) is September 9.