Weather in CROATIA

Croatia has a mixed climate, with continental climate conditions in the north and Mediterranean ones on the Adriatic.The climate is generally moderate but there is considerable difference between the Mediterranean climate of the Dalmatian coast (Zadar, Split, Dubrovnik, etc.,) and the Central European continental climatecharacterised by long, dry summers and cold winters in the inland regions (Zagreb, Osijek etc.,).

Croatia’s coast and islands up through Dalmatia to Istria and Kvarner in the north enjoy a Mediterranean climate although it’s usually several degrees cooler in the northern Adriatic than in the south. It is one of the sunniest and warmest coasts in Europe with an average of 2600 hours of sunshine yearly.

In summer, the mean temperature along the coast is between 24°C and 26°C. The warmest months are July and August, when the air temperature reaches up to 35°C. June, despite the frequent showers, and September are also very warm months, with average air temperature around 25°C and the sea temperature between 20°C and 25°C.

Sea temperatures never fall below 10 degrees in the winter and in August it can be as high as 26 degrees, due to warm currents flowing north up the Adriatic coast. The most unpleasant feature of the coastal Croatia’s winter weather is a cold and brisk wind, the Bura. This is a cold, dry wind which blows from the mainland in sudden, powerful gusts bringing dry air and cooler temperatures.

That’s why the most popular times for a yacht charter in Croatia is in the summer months between May and September, when gentle prevailing northerly winds provide easy-going sailing.

The Croatian interior which includes Zagreb and Slavonia is separated from the coast by the Dinaric mountains and has a completely different climate. In Zagreb, the average annual temperature is 12°C (53°F) with average highs of 2°C (35°F) in January and 27°C (80°F) in July.

The central mountain regions of Lika and Krbava have warm summers and cold winters, with a milder climate in the valleys. In the plains, temperatures average 20° to 24°C (68° to 75°F) in June and -2° to 2°C (28° to 36°F) in January—although they range from a low of -20°C (-4°F) in the winter to as high as 40°C (104°F) in the summer!

Temperatures
The warmest months are July and August when the air temperature is between 25° C and 35° C (77° F - 95° F) and the sea temperature reaches up to 28° C (83° F). The rain is very rare. This is the time when most of the tourists come. 
If you're for a quieter time at the beach and not so many tourists, maybe June and September are months for you. They are also very warm months with average temperatures around 25° C (77° F) and the sea surface temps between 20° C and 25° C (68° F - 77° F). 
Sunbathing and swimming is also possible in April, May and October, but it really depends on the weather and chances are that you'll get more sunshine in the southern Adriatic. In that period expect temperature between 15° C and 25° C ( 59° F - 77° F) and the sea temperature between 16 and 21° C (61 - 70° F). This is a period with more rain and windy days. 
The air temperature in winter months is between 5 and 10° C (41-50° F) and the sea temperature are in average 12 ° C (54 ° C).