One lightning bolt hit a fridge in a grocery store in Färjestaden on the island of Öland.
There was a brief power cut and the customers got frightened, staff member Malin Skoglund told Swedish Radio.
Most of the thunder storms happened over the sea but also inland on Friday morning, with the Kalmar region experiencing the most dramatic weather.
Målilla in the municipality of Hultsfred saw the biggest downpour of Midsummer Eve. According to SMHI, 12 millimetres of rain fell in the area.