Temperatures climbed to 28.8C in Gothenburg, making public holiday Ascension Day (Kristi himmelfärdsdag) the hottest so far this year – and the second hottest in Europe yesterday.
On Thursday only Voznesensk in southern Ukraine topped Gothenburg, with 29.4C, reported regional newspaper GP.
In second place in Sweden was Kärna in Bohuslän, also on the west coast, with 26.9C.
But after several days of summer weather, temperatures are about to plummet, warned national weather institute SMHI.
“We're getting a rain front from the west and maybe also thunder. In eastern Sweden tomorrow (Friday) looks set to be decent, however,” meteorologist Lars Knutsson, told the TT newswire.
But it wasn't all good news on Thursday. A forest fire near Gothenburg's Landvetter Airport caused a two-hour closure. The blaze was extinguished by firefighters and members of staff at the airport.
And a man in his 30s died after attempting to swim across a canal in the city just after midnight, said police on Friday.
For Friday, SMHI has warned of high water levels in almost all of northern and parts of central Sweden, as snow melts in the warm weather. It has upgraded the warning to a class-three alert (the most serious on a scale from one to three) in western Jämtland, Härjedalen and Dalarna.