The Kornati Islands is meteorologically located between two quite different areas: the northern Adriatic which is under the influence of Genua depressions in spring and autumn, and the southern Adriatic which is under a strong influence of the subtropical high pressure belt during the summer. Because of its comparatively small area and low elevation, the whole area of the Kornati has almost the same climate. Due to the scarcity of land vegetation, dew is usually abundant and somewhat replaces rain. According to the Köppen climate classification, the Kornati have the olive climate, Csa (moderately warm, with hot and dry summers, most of the rain falls in autumn).
The temperature varies from the average low of 8 °C in February to the average high of 25 °C in July and August. The average annual temperature is around 16 °C. The record high at the Vela Sestrica weather station was 36.4 °C while the record low was -3,8 °C. 270 days during the year are warmer than 10 °C. There is an average of 4.2 cold days (temperature lower than 0 °C) during the year. There are at least 90 warm days (temperature at least 25 °C) during the year and they start in May and last till October. Finally, there are around 40 hot days (temperature at least 30 °C) in the year – they start in May and last till September (most of them are in August, 16.9).
Cloud cover is not large: during the cloudest winter months, clouds cover just above a half of the sky on the average and only a quarter of the sky during the summer. August has 2 cloudy days on the average and 22 sunny ones. There is two times more sunny days during the year than cloudy ones, 151 against 74. Interestingly, almost every cloudy day brings rain. Maximum rainfall happens in October, while it's November in the other parts of Croatia.
The most frequent wind in the Kornati is bura (north-easterner) -– 19,4% of the year, while the strongest one is jugo (south-easterner). The dominant wind during the summer is maestral (north-westerner). In general, the flow of air from the sea to the land is dominant. Winds from 1 to 3 Beauforts, in 70% cases (from light air to gentle breeze). Strong winds (6 or more Beauforts) blow for about 37 days during the year. On the other hand, not even in December, when they are the most frequent, there is no more than 5 days of strong winds. Storm winds blow 5.8 days in the year, most often in December. Calm occurs in 15.4% of cases during the year.
There is between 2600 and 2700 sunshine hours annually. Daily insolation in winter is around 4 hours and 11 hours in summer. The ultraviolet radiation in the Kornati is only about 5% of the total solar radiation.