🇫🇮Finland

Finland extends from 59°30′ to 70°05′N across the Fennoscandian Shield, a Nordic country stretching approximately 1,160 km north to south from the Gulf of Finland to the Lapland Arctic. The Baltic Sea and Sweden lie to the west, Norway to the north, and Russia to the east. The landscape consists mostly of low forested rolling lowland dotted with around 188,000 lakes and shaped by glacial moraines.

The highest point is Halti at 1,324 m on the Norwegian border in northwest Lapland. The climate transitions from humid continental Dfb in the south (encompassing Helsinki and Turku) through subarctic Dfc across most of the country, covering Jyväskylä, Oulu, and Rovaniemi and reaching Utsjoki and Kilpisjärvi in northern Lapland, with Tampere and Kuopio near the boundary between the two.

Helsinki sees January highs around −1°C and lows around −6°C and July highs around 22°C with 660 mm of precipitation, featuring cold, often snowy winters. Tampere shows a similar pattern but slightly more continental character. Oulu on the Bothnian Bay experiences January highs around −5°C and lows around −12°C. Rovaniemi at the Arctic Circle sees winter highs around −7°C and lows around −14°C and summer highs around 20°C with a heavy, reliable winter snow cover.

Sodankylä in central Lapland can see winter lows below −40°C, and the national all-time record of −51.5°C was set at Kittilä in 1999. Summer maxima can reach 32°C or higher even in Lapland during heatwaves, with the national record of 37.2°C set at Liperi in 2010. The Bothnian Bay, the northern part of the Gulf of Bothnia, freezes over every winter.

Finland has experienced several notable climate and weather events in recent decades. The 2010 Asta–Veera–Lahja storm cluster caused significant impacts on infrastructure and forests. Finland's 2022 summer was one to two degrees warmer than the 1991–2020 average, and exceptionally warm in eastern Lapland. The Gulf of Bothnia has been losing winter ice cover, altering traditional seasonal patterns.

Meanwhile, spruce bark beetle outbreaks have become more frequent in Finnish spruce forests as conditions warm. These events (storms, heat extremes, ecological shifts, and reduced ice cover) reflect broader changes in Finland's climate system.

Our archive covers 10 Finnish cities with daily ERA5 reanalysis data going back to 1940. The hottest July afternoons are in Turku, with average highs around 21.2°C, while Oulu has the coldest January nights, with average lows near −12.7°C. Comparing the last decade against the 1940–1970 baseline, mean temperatures across these cities have risen by about 2.1°C.