September temperatures lower than normal
According to statistics of the Finnish Meteorological Institute, the average temperature for September varied between about 5 degrees Celsius in the northwest of Finnish Lapland and about 11 degrees in the southwest of Finland. September was cooler than usual in all parts of Finland. The deviation from the average for the new normal period, 1991-2020, was 1-3 degrees. September was unusually chilly in some areas in southern and central parts of the country, with temperatures that occur less frequently than once every ten years. Compared with the average, temperatures in the coolest areas in September were the lowest they had been since 1993.
September's highest temperature, 22.8 degrees, was measured on 9 September in Jomala in the Åland Islands. The lowest temperature was -6.8 degrees, recorded at Ylivieska Airport on 22 September.
September mostly cloudy and dry
Precipitation in September was significantly below the long-term average, with some areas getting only half of the normal amount of rainfall. The long-term average in the 1991-2020 normal period was mostly 50-70 mm.
Both the driest and rainiest areas in September were in Finnish Lapland. The greatest amount of precipitation was 80.1 mm. in Näkkilä in Enontekiö. Precipitation was lowest in Kirkkajärvi in Inari, 8.6 mm. The greatest amount of precipitation in a single day, 35.7 mm. was recorded at the Parainen Fagerholm observation station on 23 September.
The statistical first snow came down in mid-September at Värriötunturi in Salla on 14 September. On the following day 5 cm of snow was measured in Tornio and other locations, which is an exceptional amount on such an early date.
Most areas got 10-30 % fewer hours of sunshine than average. Only 37 cloud-to-ground discharges were observed in September, well below the average of 4 400 for the whole month.
Weather statistics from the Climate Service, tel. + 358 600 1 0601 (€ 4,01/min + local network fee)