Mean temperature change

Updated: 1 Jun 2018
Next update: 3 Sep 2018

Following the evolution of mean temperatures gives information on the progress of climate change. There are many factors that affect the temperatures. Annual and decadal temperature oscillations are related to changes in different weather types. Occasionally we get mild weather from southerly and westerly flows and occasionally colder weather from the north.

Finnish temperatures have risen approximately one degree Celsius since early 20th century. In Helsinki the urban heat island effect amplifies the warming trend. The temperature rise is not constant and it is partly obscured by the large natural variability which is characteristic for Finland. Globally however the temperature rise of over half a degree Celsius in the 20th century is statistically significant.


Spring ended with many warm days

The average temperature in Finland during spring months (from March to May) was close to long term average or slightly above it. Rather cold March
compensated the record high temperatures in May. According to Finnish meteorological institute’s statistics May was record warm.
Average temperature in Finland was 11.6 °C which is 0,5 °C warmer than the earlier record from 1963.

Minimum temperature in spring was -35,7 °C and it was measured in Utsjoki Kevojärvi March 7th. The maximum temperature was 29,6 °C and it was measured
in Kemiö, Helsinki-Vantaa airport and Kouvola Utti May 15th.

There was also record high number of hot days during spring months. The definition of hot day is that daily maximum temperature exceeds 25 °C.
The number of hot days in Finland during spring 2018 was 14 when for example in spring 2017 there was only one hot day.