An “exceptionally powerful” low pressure system is bringing potentially dangerous gusts and rough seas to western parts of Finland.
Strong southerly gale-force winds are set to lash much of the country on Saturday evening and Sunday. The Finnish Meteorological Institute (FMI) warns of severe gale force winds of 21 metres per second on Sunday afternoon on the Northern Bay of Bothnia, with Significant wave height exceeding 2.5 metres.
The FMI's warning maps are virtually covered with warning symbols, including wind advisories and forest fire alerts over much of the country.
There are wind advisories nearly throughout Finland, with warnings of strong winds with gusts of up to 20 metres per second in Ostrobothnia, Kainuu and most of Lapland on Sunday.
Briefly calmer during short night
Yle meteorologist Matti Huutonen said on Saturday afternoon that an "exceptionally powerful" low pressure system was moving along Finland’s western flank from the south to southern Lapland.
"The winds are blowing on southern maritime areas and in western Finland this evening. The gustiness will let up a bit when the sun sets but will pick up again when it rises – and after all, the sun rises quite early now," Huutonen said.
Just two weeks before summer solstice, the sun sets in Helsinki at 10.38pm and rises again at 4.03am. In northernmost Finland the sun is now below the horizon for less than two hours each night.
Rough seas for boaters
The FMI said on Saturday afternooon that strong winds had hit the south coast earlier than expected, knocking out electricity to some 12,000 households just after 4pm. An hour later that number was down to around 7,000, but by 7pm had risen again to nearly 13,000, mostly in the south west and on the west coast.
A gust of 23.9 metres per second was recorded at Tampere-Pirkkala Airport, and train service was halted between Hämeenlinna and Toijala when a tree fell onto the tracks.
On Sunday morning the strongest winds are likely to be in Southern Ostrobothnia, the FMI says, followed later in the day by Southern Lapland and Kainuu.
With the summer boating season underway, there is a small craft advisory of significant wave height exceeding four metres, especially on the Northern Baltic from Saturday evening through Sunday morning.