Finland sees record high temperature in September

The average temperature in September was record-high everywhere in Finland, according to the Finnish Meteorological Institute (FMI).

The average temperature of the month was 12.2 degrees, which shares the record with last year’s September, said the FMI in a press release on Friday.

“It is unprecedented that the average temperature is record high during the same month in consecutive years in Finland,” said Meteorologist Pauli Jokinen of FMI.

September was record warm at observation stations in the eastern and northern parts of the country. For example, the average temperature in Tähtelä, Sodankylä was 10.3 degrees Celsius in September, which is the new record for September in the measuring history spanning over 110 years, breaking the old records from 1934 and 2023 by 0.3 degrees Celsius.

Climate change made the September in Sodankylä about 1.7 degrees warmer than what it would have been without the impact of climate change. The probability of a September this warm is about 23 times higher in the current climate than without climate change, according to a peer-reviewed method by researchers at the FMI and the University of Helsinki.

The average temperature in September varied between approximately 15 degrees Celsius on the southern coast to about 8 degrees in north-western Lapland.

The deviation from the comparison period 1991–2020 was generally 2–4 degrees, with the largest deviation in eastern Finland.

The highest temperature in September, 28 degrees Celsius was recorded on the fifth day of the month in Yltöinen in Kaarina and Turku Airport, which is the highest September temperature since 1968, when the record temperature was 28.8 degrees Celsius.

The lowest temperature of the month, minus 9.8 degrees Celsius, was recorded in Vuotso, Sodankylä, on 23 September.

There were as many as eight hot days in September, which is a new record for hot days in September. The previous record - five hot days - was from 1968.

According to preliminary data, the highest amount of precipitation was recorded in Lamminkäyrä, Lapinlahti (141.1 mm).

The lowest precipitation levels were recorded in Pyhäselkä, Joensuu where the monthly precipitation was only 12.9 mm.

The greatest precipitation in a single day, 57.4 mm, was recorded at the Jaurakkajärvi observation station in Pudasjärvi on 13 September.

The first snow was recorded in Kilpisjärvi, Enontekiö on the morning of 24 September with snow depth measured at three centimetres.

First snow came a few days earlier than the median time of the comparison period 1991–2020.

At the end of the month, there was only snow at the Inari Angeli Lintupuoliselkä observation station, where the snow depth was 11 centimetres.

In September, there were 130‒200 hours of sunshine. In both the south and the north, the sun shone 20‒40 hours more than usual.

A total of 3,641 cloud-to-ground lighting strikes were observed in September, below the average of 2,800.