Trieste climate
Trieste (Friuli Venezia Giulia, Italy) has a humid subtropical climate (Köppen Cfa). The average temperature over the year is 15 °C59 °F, and about 1,026 mm40 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Trieste climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin |
|---|---|---|---|---|
| Jan | 846 | 337 | 541 | 682.7 |
| Feb | 948 | 337 | 642 | 823.2 |
| Mar | 1355 | 642 | 948 | 722.8 |
| Apr | 1763 | 1050 | 1456 | 692.7 |
| May | 2271 | 1458 | 1864 | 893.5 |
| Jun | 2679 | 1966 | 2272 | 732.9 |
| Jul | 2984 | 2170 | 2577 | 602.4 |
| Aug | 2984 | 2169 | 2577 | 793.1 |
| Sep | 2475 | 1661 | 2068 | 1134.4 |
| Oct | 1966 | 1254 | 1660 | 1024.0 |
| Nov | 1456 | 847 | 1152 | 1234.8 |
| Dec | 948 | 439 | 744 | 963.8 |
| Year | 2984 | 337 | 1559 | 1,02640 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 83% | 75% | 1.3 | 9:03 |
| Feb | 81% | 70% | 2.2 | 10:18 |
| Mar | 78% | 62% | 3.5 | 11:46 |
| Apr | 74% | 59% | 4.8 | 13:28 |
| May | 73% | 60% | 5.8 | 14:54 |
| Jun | 71% | 54% | 6.6 | 15:41 |
| Jul | 65% | 45% | 6.7 | 15:21 |
| Aug | 66% | 44% | 5.7 | 14:06 |
| Sep | 71% | 55% | 4.2 | 12:28 |
| Oct | 79% | 64% | 2.6 | 10:50 |
| Nov | 83% | 73% | 1.5 | 9:24 |
| Dec | 82% | 74% | 1.1 | 8:42 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Trieste is like
The warmest month is July, with an average high of 29 °C84 °F and a low of 21 °C70 °F. The coldest is January, when highs average 8 °C46 °F and lows 3 °C37 °F. Seasons are strongly marked: the warmest month is on average 19.8 °C35.7 °F warmer than the coldest.
It is wet, with about 1,026 mm40 in of precipitation per year. The wettest three-month stretch is September–November, which brings 33% of the annual total. The wettest month is November (123 mm4.8 in), the driest is July (60 mm2.4 in).
Relative humidity ranges from 65% in July to 83% in January. The clearest skies (lowest average cloud amount, 44%) are typical of August. Average wind speed near the ground ranges from 6 km/h (4 mph) in July to 10 km/h (6 mph) in February. Daylight lasts from about 8.7 hours in December to 15.7 hours in June.
Best time to visit Trieste
Based on these averages, the most comfortable months for sightseeing and outdoor activities are May–August: average highs of 22 °C71 °F to 29 °C84 °F with 60 mm2.4 in to 89 mm3.5 in of precipitation per month.
The most challenging month is January, which is cold, with average highs of 8 °C46 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Trieste
- Winter (December–February) — highs 846 to 9 °C48 °F, lows 337 to 4 °C39 °F, about 82 mm3.2 in of precipitation a month. Pack a warm coat, layers and closed shoes.
- Spring (March–May) — highs 1355 to 22 °C71 °F, lows 642 to 14 °C58 °F, about 77 mm3.0 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket.
- Summer (June–August) — highs 2679 to 29 °C84 °F, lows 1966 to 21 °C70 °F, about 71 mm2.8 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses.
- Autumn (September–November) — highs 1456 to 24 °C75 °F, lows 847 to 16 °C61 °F, about 113 mm4.4 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket and an umbrella or light rain jacket.
How Trieste compares
Compared with Ljubljana, about 72 km to the northeast, Trieste is on average 3.5 °C6.2 °F warmer and receives a similar amount of precipitation. The difference is largest in December (4.5 °C8.2 °F warmer).
Of the 37 places in Italy covered by World Climates, Trieste is the 23rd warmest by annual mean temperature and the 2nd wettest by annual precipitation. See all of them on the Italy climate page.
Places in other countries with the most similar temperature and rainfall pattern: Mostar (Bosnia and Herzegovina, Csa), Düzce (Turkey, Cfa) and Nîmes (France, Csa).
Nearby places
- Udine 63 km · 14 °C56 °F · 1,074 mm42 in
- Rijeka 63 km · 13 °C56 °F · 1,197 mm47 in
- Ljubljana 72 km · 11 °C52 °F · 1,051 mm41 in
- Klagenfurt am Wörthersee 116 km · 10 °C51 °F · 1,060 mm42 in
- Mestre 120 km · 15 °C59 °F · 943 mm37 in
- Padua 150 km · 15 °C58 °F · 879 mm35 in
- Zagreb 172 km · 11 °C53 °F · 906 mm36 in
- Vicenza 174 km · 15 °C58 °F · 865 mm34 in
Frequently asked questions
What is the warmest month in Trieste?
July is the warmest month in Trieste, with an average high of 29 °C (84 °F) and an average low of 21 °C (70 °F).
What is the coldest month in Trieste?
January is the coldest month, with an average high of 8 °C (46 °F) and an average low of 3 °C (37 °F).
When does it rain the most in Trieste?
November is the wettest month with about 123 mm (4.8 in) of precipitation; July is the driest with about 60 mm (2.4 in).
What is the best time to visit Trieste?
Judging by long-term averages, the most comfortable months are May–August.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 256 m, while Trieste lies at about 2 m. Temperatures on this page were therefore adjusted by +1.7 °C3 °F using the standard lapse rate of 6.5 °C per 1,000 m.