Southern parts of the country were first to feel the change as heavy showers and thunderstorms struck early on Saturday morning.
Götaland and western Svealand are expected to bear the brunt of the thunder and lightning, with meteorological agency SMHI issuing a Class 1 weather warning for the south – the lowest level on a scale from 1 to 3.
The stormy weather will later northwards across the country as Norrland prepares to face on onslaught of thundery showers on Sunday.
Anybody currently out at sea is being advised to seek out a safe haven to avoid being caught up in the gathering storm.
“It’s important to choose places for boats that are well protected. Winds may become strong for a short period overnight in connection with the thunderstorms,” said meteorologist Sten Laurin.
He was however quick to underline that Sweden has not seen the last of the current heatwave.
“It’s going to remain warm over the coming days and temperatures could climb back up to 30 degrees in Småland, for example, towards the end of the week. The weather will be a bit more unsettled in general.”