Extended drought conditions in several Mediterranean countries, a heat wave last week that reached northern Germany and high fuel costs for aircraft needed to fight wildfires have heightened concerns across Europe this summer.

And it’s only June.

“Much of the continent is in drought,” said Cathelijne Stoof, an environmental science professor at the Netherlands’ Wageningen University, who called the wildfire outlook “very challenging across Europe.”

Fires last summer blackened more than 11,000 square kilometers (4,250 square miles) of land — an area more than four times the size of Luxembourg. About half of the damage was in the European Union.

And, experts say, Europe’s wildfires aren’t just a problem for the southern, hotter countries.

“What scientists are warning us is that (fires) are obviously going north and in countries such as the U.K., in countries such as Germany as well as in Scandinavian countries, in the future, we need to expect wildfires to happen more often,” said Catherine Gamper, a climate change adaptation specialist at the Organization for Economic Cooperation and Development.

Wildfires across Spain have destroyed tens of thousands of acres of wooded land, though a recent sharp drop in temperatures is helping firefighters contain them.