Weather and climate in the northern Adriatic

Weather forecast

There's a simple forecast on the left. For a forecast of wind and wave conditions in the northern Adriatic, click the link. This information is also displayed in the marina office.

Climate overview

Located between the Adriatic Sea in the south and mountains to the north, Trieste enjoys a climate that is quite different from other parts of northern Italy.

Visitors can expect Mediterranean-style weather in the summer, with plenty of sunshine and high temperatures, as well as mild winters. Trieste does experience a fair amount of rainfall throughout the year, so both summer and winter visitors should come prepared with appropriate gear. Trieste records the smallest temperature differences between winter and summer and between day and night.

Temperature

The warm season lasts from June to early September with an average daily high temperature above 25°C. The hottest time of the year is July, with an average high of 29°C and low of 18°C.
The cold season lasts from November to March with an average daily high temperature below 12°C. The coldest time of the year is January, with an average low of -0°C and high of 8°C.

Sunshine

The length of the day varies significantly over the course of the year. The shortest day is December 21 with 8:28 hours of sunlight; the longest day is June 20 with 15:33 hours of sunlight.

Rainfall

The probability of rain varies throughout the year. Over the entire year, the most common forms of precipitation are thunderstorms, moderate rain, and light rain. Thunderstorms are most likely in July; moderate rain and light rain are most likely in April. During the warm season, there is a 44% average chance that precipitation (often in the form of thunderstorms) will be observed at some point during a given day.

Humidity

The relative humidity typically ranges from 44% (comfortable) to 96% (very humid) over the course of the year, rarely dropping below 30% (dry) and reaching as high as 100% (very humid). The air is driest in July, and most humid in September, exceeding 94% (very humid) three days out of four.

Wind

Over the course of the sailing season, typical wind speeds are in the 10 to 20 knot range (5 to 10m/s). Most of the time the wind blows from the east, and least often from the west.
In the winter months, the winds are mostly light to moderate, but the katabatic bora can sometimes blow at gale force for several days.