Autumn, as defined by meteorologists, arrived late in Kyiv
The average monthly air temperature in Kyiv in September was +16.3°C, which is 1.4°C above the climatic norm. In addition, according to observations on Nauky Avenue, the first month of fall turned out to be quite rainy—the capital received 86 mm of precipitation, which is 148% of the monthly average.
The coldest day of September was the 23rd, when the temperature dropped to +5.9°C in the early morning, and the warmest was September 10, with a high of +29.7°C. Meteorological autumn, which is defined as the point at which the average daily temperature consistently falls below +15°C, began in the capital on September 21, five days later than the long-term average.

Source: Boris Sreznevsky Central Geophysical Observatory
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