Trieste, Italy Climate & Monthly Averages
Trieste has a humid subtropical climate. July is the hottest month, averaging 85° by day; January is the coldest at 47°.
Sunshine is a defining feature of Trieste's climate
Trieste records 127 wet days and 9.1 hours of daily sunshine in an average year. Temperatures follow a humid subtropical pattern, running 47°F (9°C) in January up to 85°F (29°C) in July.
How sun, temperature and rain fit together
January is the coolest month, with highs of 47°F (9°C) and lows near 36°F (2°C). At its warmest, in July, Trieste runs to 85°F (29°C) in the afternoon and back to 69°F (21°C) by dawn. Snow falls on roughly 4 days a year, mostly January through March.
The wettest month is September (7.4 inches (189 mm) across 11 days) and the driest April. Three of the twelve months pair mild highs with fewer than twelve wet days; the longest unbroken run is September through October. Days and nights are about 7°C apart on average - narrower than about 76% of the cities we track. Across the gridded 2015-2024 daily record, the highest daily maximum for this location was 98°F (36°C) and the lowest daily minimum 20°F (-7°C).
More climate facts for Trieste
- Hottest month: July - highs near 85°F (29°C)
- Coldest month: January - highs near 47°F (9°C)
- Decade extremes (2015-2024): 98°F (36°C) high · 20°F (-7°C) low
- Wettest month: September (11 rainy days) · Sunniest: July (13.2 h sun/day)
- Climate type: humid subtropical
- Annual swing: 20°C between the average warmest and coolest month · day to night: 7°C
- Snow: about 4 days a year
- Average humidity: 71%
The most comfortable sunny-weather window
Best time to visit Trieste
September to October and April is the sweet spot for Trieste - warm days, manageable rainfall and plenty of daylight line up. Expect 71°F (22°C) in the afternoon and around 10 days of rain in a typical month of it. For the same question asked the other way round, see where else is warm in September.
What to pack
Pack for Trieste with light clothing for the warm months, a warm jacket and layers for the cooler season and a compact umbrella or rain shell. July nights average 69°F (21°C), so evenings rarely match the afternoons.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Daylight | Wet-day chance | Humidity |
|---|---|---|---|---|---|---|---|---|
| January | 47° | 36° | 10 | 3.8 in | 5.8 h/day | 9.1 h | 31% | 74% |
| February | 51° | 39° | 11 | 4.3 in | 6.6 h/day | 10.3 h | 38% | 73% |
| March | 56° | 42° | 10 | 3.6 in | 8.9 h/day | 11.8 h | 31% | 68% |
| April | 63° | 48° | 9 | 3.4 in | 10.3 h/day | 13.5 h | 31% | 67% |
| May | 70° | 56° | 15 | 5.9 in | 10.8 h/day | 14.9 h | 50% | 72% |
| June | 79° | 65° | 10 | 4.0 in | 12.8 h/day | 15.7 h | 32% | 69% |
| July | 85° | 69° | 8 | 3.6 in | 13.2 h/day | 15.4 h | 27% | 64% |
| August | 85° | 69° | 8 | 3.7 in | 12.2 h/day | 14.1 h | 26% | 64% |
| September | 75° | 62° | 11 | 7.4 in | 10.0 h/day | 12.5 h | 37% | 69% |
| October | 67° | 55° | 12 | 6.7 in | 7.8 h/day | 10.8 h | 38% | 75% |
| November | 56° | 46° | 13 | 6.6 in | 5.8 h/day | 9.4 h | 42% | 76% |
| December | 50° | 39° | 11 | 4.8 in | 5.1 h/day | 8.7 h | 35% | 76% |
Trieste month by month
Each card shows the average high and low. The bar places that month between Trieste's coldest night and warmest afternoon.
January
- Rain
- 10 days
- Sunshine
- 5.8 h
- Daylight
- 9.1 h
- Snow
- 1 day
February
- Rain
- 11 days
- Sunshine
- 6.6 h
- Daylight
- 10.3 h
- Snow
- 1 day
March
- Rain
- 10 days
- Sunshine
- 8.9 h
- Daylight
- 11.8 h
April
- Rain
- 9 days
- Sunshine
- 10.3 h
- Daylight
- 13.5 h
May
- Rain
- 15 days
- Sunshine
- 10.8 h
- Daylight
- 14.9 h
June
- Rain
- 10 days
- Sunshine
- 12.8 h
- Daylight
- 15.7 h
July
- Rain
- 8 days
- Sunshine
- 13.2 h
- Daylight
- 15.4 h
August
- Rain
- 8 days
- Sunshine
- 12.2 h
- Daylight
- 14.1 h
September
- Rain
- 11 days
- Sunshine
- 10.0 h
- Daylight
- 12.5 h
October
- Rain
- 12 days
- Sunshine
- 7.8 h
- Daylight
- 10.8 h
November
- Rain
- 13 days
- Sunshine
- 5.8 h
- Daylight
- 9.4 h
December
- Rain
- 11 days
- Sunshine
- 5.1 h
- Daylight
- 8.7 h
Looking for warmer alternatives? Browse warm places by month, or compare Trieste's coolest part of the year: January, December, February.
Seasonal weather under Trieste's sunnier skies
Spring (March through May)
Through spring, Trieste is crisp but comfortable: 63°F (17°C) by day, 49°F (9°C) after dark, and rain falls on around 34 of the 90 days. Daylight is generous - around 10.0 hours of sun a day.
Summer (June through August)
Summer sits firmly in the heat here - highs near 83°F (28°C), nights near 68°F (20°C), and expect showers on roughly 26 days across the season. Daylight is generous - around 12.7 hours of sun a day. With the moisture factored in, afternoons feel hotter than the reading suggests - the humidity and dew point converter shows why.
Fall (September through November)
Through fall, Trieste runs cool rather than cold: 66°F (19°C) by day, 54°F (12°C) after dark, and rain falls on around 35 of the 90 days.
Winter (December through February)
Winter is brisk and cold here - highs near 50°F (10°C), nights near 38°F (3°C), and rain falls on around 31 of the 90 days, plus about 3 snowy days.
How unusual is Trieste?
- Trieste sits close to the middle of our dataset on most measures: 58°F (15°C) as an annual average, 58.0 inches (1473 mm) of precipitation and 9.1 hours of sun a day.
These comparisons use the same ten-year window for every city in the dataset.
Trieste temperature extremes in the 2015–2024 dataset
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ. Need another precipitation unit? Use the rainfall converter.