Greek authorities are warning of extreme heat in the midst of the tourist season, with a high risk of fires. Parts of southern and central Europe are plagued by high temperatures.
Southwesterly winds from Africa are bringing temperatures above 40 degrees, at least until July 19, warns the department for civil protection and climate change in Greece.
The new heatwave comes shortly after Greece experienced its hottest June month ever.
People are being advised to wear light clothing, drink plenty of water, and avoid long walks during the hottest part of the day. In June, several tourists were found dead on Greek islands after embarking on longer treks on foot.
Neighboring North Macedonia has also issued a heat warning, effective from Friday.
In Hungary, a heat warning is in effect until July 18. An airport in eastern Hungary has been closed since a runway was damaged by the heat. Flights are being diverted to Budapest at least until Sunday.
On the Spanish sun coast, the country's weather agency has issued a heat warning at the yellow level, ahead of what is expected to be the summer's first heatwave, according to regional media. In Málaga, the temperature rose to 36 degrees on Friday.