China News Service, Beijing, September 27 (Reporter Chen Hang) The reporter learned from the Beijing Meteorological Department that this year's Beijing Meteorological Observation Representative Station Observatory will enter the autumn on September 19, and the annual (1991-2020 average) will enter the autumn time. for September 13.

Due to the weak cold air force in mid-September, the temperature in Beijing continued to be high, so autumn entered later than usual.

  The Chinese meteorological industry standard - "Climate Seasonal Division" stipulates that the 5-day sliding average temperature is calculated based on the current year's temperature series to form a sliding average temperature series. When the five-day sliding average temperature series is less than 22°C for 5 consecutive days, the corresponding The first date in the temperature sequence that is less than 22°C is the start date of autumn. If the start date of the initial judgment is more than 15 days earlier than normal, a second judgment of the start date is required.

  According to the meteorological department, this year, the sliding average temperature series began to be less than 22 °C since September 22, and reached a temperature of less than 22 °C for 5 consecutive days on September 26. The corresponding date in the temperature sequence is September 19 (21.5 ℃), the annual fall entry date is September 13, and there is no need to make a second judgment. Therefore, the autumn entry date this year is determined to be September 19.

  The meteorological department said that from the 27th to the 30th, Beijing will be dominated by sunny to cloudy weather. The highest temperature during the day is between 29 and 30 degrees Celsius, and the lowest temperature at night is between 17 and 18 degrees Celsius. The temperature difference between day and night is large, and the morning and evening are full of coolness. It is hot in the afternoon, please add or remove clothes in time according to the temperature change.

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