This summer has been warm with plenty of regional variation, especially in rainfall amounts, meteorologist Ville Siiskonen of the Finnish Meteorological Institute (FMI) said on Thursday.
This summer's highest temperature, 32.9 degrees Celsius, was measured on 28 June at Pori Airport. It was also sweltering a day later in Utsjoki, Finland's northernmost municipality at 32.5 degrees. The season's average temperature has been the highest in the Kuopio region of eastern Finland.
The heaviest rainfall was on 5 August in Seinäjoki, South Ostrobothnia, which was soaked by nearly 91 millimetres of precipitation in a day. It has been wet in the region otherwise, with the highest total summer rainfall not far away in Karijoki.
Officially, the meteorological summer ends at the end of August, but a review period of 1 June-21 August indicates that the average temperature this summer has been one to two degrees warmer than the average in the 1991–2020 period.
Exceptionally warm in Lapland
"There are regional differences, but for example it has been exceptionally warm in the northern part of the country, especially the eastern part of Lapland," Siiskonen said.
In the long-term statistics, the average summer temperature varies from 10–11 degrees in northern Lapland to just over 16 degrees in the southern part of the country.
"In the longer comparison period, the average temperature in Eastern Lapland is 11–13 degrees, but this year it's been generally 14 or even close to 15 degrees," the meteorologist told Yle.
In southern Finland, average summer temperatures rose to 18.1 degrees in several places, including Vantaa, Lapinjärvi, Iitti and Kouvola.
Latest "tropical night" on record in Helsinki
The highest summer temperatures were measured between 26 June and 2 July, with readings over 32 in places such as Pori, Utsjoki, Espoo and Kokemäki.
According to Siiskonen, thermometers in Finland don't reach 32 degrees every summer, but it has not been rare in recent decades.
"In the last four summers, the highest temperature has been over 33 degrees, and last summer's highest was 34," he said.
A day earlier, Siiskonen's colleague Mika Rantanen, a researcher at the FMI's Weather and Climate Change Impact Research unit, tweeted that Wednesday's daily minimum temperature in Helsinki was 20 degrees, the highest on record this late in the summer.
With the mercury never dropping into the teens during a 24-hour period, this was the latest so-called "tropical night" in Helsinki's Kaisaniemi Park since record-keeping began in 1844.
Earlier in August, Rantanen attracted headlines around the world as the lead author of a study (siirryt toiseen palveluun) published in the journal Nature showing the Arctic region has warmed nearly four times faster than the whole planet since 1979.