Copernicus Earth Observation Programme said 60 fires are burning in Sweden, while further fires have also been reported in Norway, Finland and Russia.
Several of those fires are burning inside the Arctic Circle and national authorities have been forced to call for international aid from the EU.
Threat of further fire is “extremely high” Swedish authorities said, with temperatures expected to reach higher than 30 degrees in the coming days.
Thousands of residents have been warned to remain inside to protect themselves from smoke inhalation, while others have been evacuated from their homes.
Last year was the worst year in European history for wildfire outbreaks and similar hot conditions and drought across the region have sparked the latest blazes.
“What we’re seeing with this global heatwave is that these areas of fire susceptibility are now broadening, with the moors in north-west England and now these Swedish fires a consequence of that,” Vincent Gauci, professor of global change ecology at the Open University told Guardian Australia.