Severe thunderstorms hit southern Finland, flooding basements and felling hundreds of trees

A violent thunderstorm front swept across southern Finland late Saturday and into Sunday, triggering dozens of emergency response calls as water flooded buildings and trees fell.

In western Uusimaa alone, emergency services handled over 40 incidents overnight, while central Uusimaa reported around 30. Most calls in western Uusimaa involved flood damage control, with basements in Espoo particularly affected.

“All in all, it was a busy night, but storms are the kind of tasks we’re prepared for,” said Jesse Mikkonen, duty chief at the Western Uusimaa Emergency Services.

In central Uusimaa, incidents were concentrated along the Kerava-Vantaa axis, with isolated reports from Hyvinkää and Nurmijärvi, mostly due to fallen trees. Eastern Uusimaa also saw numerous calls for downed trees, particularly in Sipoo.

“A squall line passed over a relatively small area. Here in Sipoo, hundreds of trees are down. We’re clearing them everywhere,” said Antti Virtanen, duty fire chief for Eastern Uusimaa Emergency Services.

Helsinki reported no additional storm-related alerts. In the Turku region of Southwest Finland, a severe thunderstorm struck around midnight, flooding a railway underpass in the city center and sparking a couple of rural fires.

Kymenlaakso, Päijät-Häme, and Kanta-Häme received reports of fallen trees but no major damage, with the highest concentration of incidents in the Kotka area.