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Trieste weather by month: averages, rainfall & climate trends

Average temperatures in Trieste follow a clear seasonal rhythm, rising and falling by 18.8°C over the course of the year. No season stands out as markedly wetter. Precipitation arrives fairly evenly year-round. Trieste weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+5.1°Chigh well above average

22° / 18°Today
17° / 12°Average
see today in detail →

How it's changed

+2.4°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–493frost days a year now (2016–2025) · 35 in the 1940sfrost days a year · 35 in the 1940s26days above 30°C a year now (2016–2025) · 5 in the 1940sdays above 30°C · 5 in the 1940s+2.4°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 103 mmhigh 7°low 2°February, rain 100 mmhigh 8°low 3°March, rain 110 mmhigh 12°low 6°April, rain 123 mmhigh 16°low 10°May, rain 128 mmhigh 20°low 14°June, rain 127 mmhigh 24°low 18°July, rain 104 mmhigh 27°low 20°August, rain 120 mmhigh 27°low 20°September, rain 157 mmhigh 23°low 17°October, rain 172 mmhigh 18°low 12°November, rain 181 mmhigh 12°low 8°December, rain 132 mmhigh 8°low 4°wettest month November, 181 mm · 1,557 mm a yearsee month by month →

Right now

What it's doing today vs the historical average for this date.
Light rain

Right now

19.1°

19°feels like
85%humidity
17°dew point
16 km/hfrom SE
UV index0.8
sunrise07:29sunset18:09day length10h 40m
TodayOvercast22°18°
ThuOvercast18°14°
FriOvercast17°12°
SatRain15°11°
SunOvercast14°11°
MonPartly cloudy18°11°
TueClear18°12°

On this date: October 21

Today (forecast)
22° / 18°
Average for October 21
17° / 12°

High well above average · +5.1°C

  • Highest since 1940: 22.4° · 2019
  • Lowest since 1940: 5.4° · 1972
  • One year ago: 16° / 15°

Every October 21 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 21 on record (n = 86). Outlined dots are today's forecast.

Area we sample

Each city's history comes from one ERA5 grid cell, about 28 km across, shown by the dashed box. Near mountains or coasts, conditions can vary across the cell.

Location & data

Historical weather for Trieste is sampled from the ECMWF ERA5 reanalysis at 45.65°N, 13.78°E, with daily records since 1940.

Coordinates
45.65°N, 13.78°E
Time zone
Europe/Rome
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

24 of the last 30 days were warmer than the historical average for that date. Average difference: +1.4°C.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above average; cool bars ran below. The dot inside the bar is the daily mean. The shaded band is the typical 10–90% range expected for that date. Average = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

This date over the years

One dot per year, showing the mean temperature on this calendar date. Dots are warmer or cooler than the long-term average (dashed line); the shaded band is the typical 10–90% range, and the highlighted dot is today's forecast. Based on ERA5 reanalysis: modelled estimates, not station readings.

Weather by month

Average temperatures and rainfall for each month: a typical year, from the full record.

Climate overview

The warmest month is July, with typical afternoon highs of 26.8°C and nights around 20.0°C. In a typical recent year, around 25 days reach 30°C or more. At the other extreme, January brings afternoon highs of about 6.9°C and typical overnight lows of 2.5°C.

Trieste picks up roughly 1,557 mm a year, with a peak of 181 mm in November and as little as 100 mm in February.

The record here starts in 1940, and since then the annual mean in Trieste has climbed 2.4°C from the first ten years to the last ten. Where the first decade averaged 35 frost days a year, the recent one saw about 3.

Climate graph (climograph)

July is the warmest month, January the coolest: a yearly swing of 19°C. Wettest month: November (~181 mm). Whole year averages ~1,557 mm of rain.

Bars = average monthly rainfall (right axis). Lines = average daily high and low (left axis). Average = each month's value averaged across every year of record (1940–2026).

Rainy days by month

About 119 rainy days a year: most in May (~12), fewest in February (~8).

Bars = average number of days with ≥ 2 mm per month. Hover for the monthly rainfall total.

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre: the record's own proxy for how sunny the month is.

Trieste month by month: what to expect

Typical conditions for each month, averaged across the full record (since 1940). Daylight is the time from sunrise to sunset. Highest and Lowest are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainRainy daysDaylightHighestLowest
January6.9°2.5°103 mm98.9 h15.1° (1944)−17.0° (1942)
February8.4°3.2°100 mm810.1 h20.4° (2021)−18.3° (1940)
March11.9°5.9°110 mm911.6 h22.2° (2017)−10.2° (1963)
April15.9°9.6°123 mm1113.3 h25.8° (2012)0.3° (1986)
May20.4°14.1°128 mm1214.7 h30.3° (2009)4.7° (1957)
June24.3°17.9°127 mm1115.5 h34.7° (2003)9.6° (1962)
July26.8°20.0°104 mm915.2 h36.1° (2015)12.3° (1948)
August26.7°19.8°120 mm913.9 h35.4° (2017)11.5° (1940)
September22.8°16.5°157 mm912.3 h31.7° (2024)7.4° (1977)
October17.8°12.3°172 mm1110.7 h27.0° (2011)0.6° (1941)
November12.2°7.9°181 mm129.2 h21.7° (2004)−6.4° (1965)
December8.3°4.2°132 mm98.5 h18.8° (2023)−10.9° (1940)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +2.4°C.

Each vertical stripe is one year. Color encodes how much that year's annual mean differed from the long-term average. Average = each year's annual mean compared to the average of all years (1940–2026). cooler ← → warmer

Annual mean temperature

Long-term trend: +0.28°C per decade.

One point per year, showing the temperature averaged across the whole year. The dashed line is the least-squares long-term trend. Based on ERA5 reanalysis: modelled estimates, not station readings.

Seasonal warming

Dec–Feb is warming fastest: +0.39°C per decade.

Each faint line is one three-month period's average per year; the bold dashed line is its long-term trend. Different parts of the year often warm at different rates. Based on ERA5 reanalysis: modelled estimates, not station readings.

Hot days vs frost days

Days ≥ 30°C per year: 5.2 early in the record → 26.2 recently. Frost days: 35 → 3.

Thin lines are raw yearly counts; thick lines are the smoothed trend that removes year-to-year noise. The hot-day threshold is auto-picked per city so the line actually moves. Average = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

Hottest day since 1940 in 2015, coldest in 1940: 36.1°C / −18.3°C.

One point per year: the single hottest and coldest day recorded that year.

Annual rainfall

~1,557 mm/year on average. Last decade: +2% vs that average. Long-term trend: +22 mm per decade.

One bar per year of total rainfall. Dashed line is the long-term average. Average = the average annual rainfall across every year of record (1940–2026).

Day-by-day grid

Each tiny square is one calendar day across the full record, about 30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical average for that date (red = warmer, blue = cooler), Daily mean temp shows the absolute mean temperature for the day (useful to see seasons and heatwaves), and Precipitation shows daily rainfall (useful to spot wet/dry seasons and droughts). Average = the long-term average for that calendar date (1940–2026).

Frequently asked questions about Trieste

Which is the warmest month in Trieste?
On long-term average, the warmest month in Trieste is July (mean daily temperature of about 23.4°C) and the coolest is January (about 4.6°C).
How does today's temperature in Trieste compare to the historical average?
On October 21, 2026, Trieste is forecast to reach a high of 21.8°C and a low of 18.0°C. The long-term average for this date (the full record since 1940) is a high of 16.7°C and a low of 11.7°C, so today's high is 5.1°C warmer than that average.
How much has Trieste warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Trieste is about 2.4°C warmer.
How much does it rain in Trieste?
Trieste receives about 1,557 mm of precipitation per year on long-term average, with November typically the wettest month.
What is the average temperature in Trieste?
Over the full record (since 1940), the annual mean temperature in Trieste is about 14.0°C. The warmest month is July and the coolest is January.
What are the average temperatures in Trieste by month?
Average daily highs and lows for each month in Trieste (°C, full record since 1940): January 7°/2°, February 8°/3°, March 12°/6°, April 16°/10°, May 20°/14°, June 24°/18°, July 27°/20°, August 27°/20°, September 23°/17°, October 18°/12°, November 12°/8°, December 8°/4°.
What is the weather like in Trieste in summer?
In summer, June through August, Trieste is wet and pleasantly warm. Afternoons run 24–27°C and nights 18–20°C; July is the warmest month. Rain is steady at around 117 mm a month, spread over roughly 10 days.
What is the weather like in Trieste in winter?
December to February is winter in Trieste, and it is wet and cold. Expect 7–8°C by day and 2–4°C at night, with January the coldest month. Rain falls on about 9 days a month, adding up to around 112 mm.
What is the weather like in Trieste in spring?
Spring in Trieste (March to May) is wet and fairly mild. March is still 12°C in the afternoon and 6°C at night, May already 20°C and 14°C. Rain is steady at around 121 mm a month, spread over roughly 11 days.
What is the weather like in Trieste in autumn?
September to November is autumn in Trieste, and it is wet and fairly mild. It cools from 23°C by day and 17°C at night in September to 12°C and 8°C in November. Rain falls on about 10 days a month, adding up to around 170 mm. It is the wettest season of the year.
How many days a year does it rain in Trieste?
On long-term average, Trieste has about 119 days a year with at least 2 mm of rain or snow. The annual total is roughly 1,557 mm.

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