Firefighters are struggling with several forest fires, while some houses near Montenegro's coastal city of Herceg Novi were evacuated.
Croatian and Montenegrin firefighters were tackling several forest fires along the Adriatic coast on Sunday, some of which forced people to evacuate their homes, local media reported.
Fires were reported near the northern city of Pula and as far south as around Sibenik, as well as on the islands of Pag and Vir and northeast of the biggest coastal city, Split.
Croatia's coast, always packed with tourists in the summer, often suffers forest fires during the holiday season and these are the fiercest so far this year.
Strong northerly winds have made putting the fires out more difficult, and authorities have issued a warning about using naked flames in the open air.
Two firefighting planes managed to stop the blaze reaching houses in the village of Brodarica near Sibenik, and a local road near the village of Sestanovac, inland from Split, was closed due to the smoke.
To the south of Croatia, people were forced to evacuate some houses near Montenegro's coastal city of Herceg Novi, Montenegrin state television said. Fires were also reported around the capital of Podgorica.
Further inland, in neighbouring Bosnia, firefighters are also struggling to get fires near the southern cities of Mostar and Trebinje under control.