Trieste weather in May

In May, Trieste sees average daytime highs of 19°C and overnight lows near 13°C, with 122 mm of rain across 13 wet days and about 14.7 hours of daylight. It is the 5th-warmest and 5th-wettest month of the year here.

Highs climb over the month, from about 18°C in the first days to 21°C by the end. The sky is clear or mostly clear about 36% of the time in May, and the air most often feels dry.

Daylight stretches from about 14 hours at the start of May to 15 h 12 min by month's end. Set against the rest of the year, May is Trieste's 5th-clearest and 9th-windiest month. For the whole year in context, see Trieste's year-round climate.

Daytime high
19°
5th warmest
Overnight low
13°
8th coldest
Rainfall
122 mm
13 wet days
Daylight
14 h 42 min
4:40 AM – 7:22 PM
Cloud cover
55%
5th clearest
Wind
9 km/h
9th windiest
Solar energy
5.68 kWh/m²
Travel score
5.8
out of 10
Air quality
Moderate
PM2.5 12 µg/m³ · 2019

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 18°C in the first days to 21°C by the end.

A typical May day in Trieste reaches about 19°C in the afternoon and slips back to 13°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 15°C and 23°C. Set against its neighbours, May runs about 5°C warmer than April and about 4°C cooler than June.

10°15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
11711
21811
31811
41812
51812
61812
71812
81812
91812
101912
111912
121913
131913
141913
151913
161913
171913
181913
192013
202013
212014
222014
232014
242014
252014
262114
272114
282115
292115
302115
312115

How May really feels in Trieste

Once humidity and wind are folded in, May averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

May sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Trieste weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 909.52.78.90.5
Feb / 978.62.910.11.1
Mar11° / 1019.71.611.62.7
Apr15° / 11012.10.513.34.2
May19° / 13°12213014.75.8
Jun23° / 17°11112.2015.46.7
Jul26° / 19°8710.7015.17.0
Aug26° / 19°11110.3013.97.0
Sep21° / 15°17011.4012.36.4
Oct16° / 11°184130.110.74.8
Nov11° / 19513.21.19.32.5
Dec / 12910.12.18.60.9

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 36% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 19% of May, with mostly cloudy or overcast conditions the remaining 46%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15149
25050
35050
45149
55149
65149
75248
85248
95248
105248
115347
125347
135347
145446
155446
165446
175545
185545
195644
205644
215743
225743
235743
245842
255842
265842
275842
285842
295743
305842
315842

Chance of precipitation in May

Any precipitation

Trieste gets around 122 mm of rain over 13 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 43% and peaks near 45% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
143
244
344
444
545
645
745
844
944
1044
1143
1243
1343
1442
1542
1642
1742
1841
1941
2041
2140
2240
2340
2440
2541
2641
2742
2842
2943
3043
3144

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

Most of May feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, May lands in the dry band about 67% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
192800
2901000
3891100
4871300
5861400
6841600
7831700
8811900
9802000
10782200
11772300
12752410
13732610
14722710
15712810
16683020
17673120
18653230
19643330
20623440
21603550
22583660
23573670
24543790
255238100
265038120
274839140
284539150
294339170
304139191
313840211

Wind in May

Winds average 9 km/h in May.

Across May, daily wind ranges from about 8 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
99calm
109calm
119calm
129calm
139calm
149calm
159calm
169calm
179calm
189calm
199calm
209calm
219calm
229calm
239calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm
318calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 14 hours at the start of May to 15 h 12 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 72 minutes over May. Sunrise moves from 5:01 AM to 4:26 AM, and sunset from 7:03 PM to 7:38 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.05:017:03
214.14:597:05
314.14:587:06
414.24:567:07
514.24:557:09
614.34:537:10
714.34:527:11
814.44:507:12
914.44:497:14
1014.54:487:15
1114.54:467:16
1214.54:457:17
1314.64:447:19
1414.64:427:20
1514.74:417:21
1614.74:407:22
1714.74:397:23
1814.84:387:25
1914.84:377:26
2014.94:367:27
2114.94:357:28
2214.94:347:29
2315.04:337:30
2415.04:327:31
2515.04:317:32
2615.14:307:33
2715.14:297:34
2815.14:287:36
2915.14:287:36
3015.24:277:37
3115.24:267:38

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.68 kWh/m².

For context, solar energy here swings from a low near 1.14 kWh/m² to a high of 6.28 kWh/m² in July across the year — May's 5.68 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.3Bright
25.3Bright
35.3Bright
45.3Bright
55.3Bright
65.4Bright
75.4Bright
85.4Bright
95.5Bright
105.5Bright
115.5Bright
125.5Bright
135.5Bright
145.6Bright
155.6Bright
165.6Bright
175.7Bright
185.7Bright
195.7Bright
205.8Bright
215.8Bright
225.8Bright
235.8Bright
245.9Bright
255.9Bright
265.9Bright
276.0Bright
286.0Bright
296.0Bright
306.0Intense
316.0Intense
Planning a trip in May

Is May a good time to visit Trieste?

Our two travel scores rate May for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.8
Sightseeing
5th-best month of the year
2.7
Beach & pool
5th-best month of the year

May is a reasonable time to visit Trieste for sightseeing.

What to pack for Trieste in May

From May's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In May, Trieste sees daytime highs around 19°C and nights near 13°C. Worth packing: rain gear and sun protection. About 13 days see rain.

rain gearsun protection

Sea temperature near Trieste in May

The nearest coast averages about 18°C in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 25°C and coldest in February near 10°C.

It's comfortable for a long swim from May 31 to Oct 9 — about 4.3 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan11Bracing
Feb10Bracing
Mar10Bracing
Apr13Bracing
May18Cool
Jun23Refreshing
Jul25Warm
Aug25Warm
Sep23Refreshing
Oct19Cool
Nov16Cool
Dec13Bracing

UV index in Trieste in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Trieste peaks around July 15 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 15UV 8Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar4Moderate
Apr7High
May7High
Jun8Very high
Jul8Very high
Aug7Very high
Sep5Moderate
Oct3Moderate
Nov2Low
Dec1Low

Air quality in Trieste in May

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where May falls, not just the annual average.

Air quality in Trieste is worst in January — around 16 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (September, 9 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Trieste's WHO annual average of 12 µg/m³.

01020JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateJan 1816 µg/m³Sep 149 µg/m³
PM2.5 (µg/m³)Level
Jan16Moderate
Feb14Moderate
Mar14Moderate
Apr13Moderate
May11Good
Jun12Good
Jul12Good
Aug10Good
Sep9Good
Oct10Good
Nov10Good
Dec13Moderate
Location & terrain

Where is Trieste?

Trieste sits at 45.6°N, 13.8°E, 2 m above sea level, in Italy. The nearest listed city is Koper, 12 km away.

Topography around Trieste

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Trieste.

Within 3 km, the terrain around Trieste has significant variations in elevation — a maximum elevation change of 451 m around an average of 72 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 779 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,524 m.

The land around Trieste is covered by artificial surfaces (41%), trees (31%) and water (27%) within 3 km, trees (50%) and water (32%) within 16 km, and trees (52%) and water (23%) within 80 km.

3 km
451 m
16 km
779 m
80 km
2,524 m
treesshrubsgrasslandcroplandartificial surfaceswater
May weather nearby: Koper 12 km · Divača 16 km · Piran 21 km · Monfalcone 26 km · Gorizia 35 km · Nova Gorica 36 km · Postojna 37 km · Udine 63 km

Italy travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / F / L
230 V · 50 Hz
Prices
≈ 69% of US
price level, 2025
GDP per capita
$43,309
2025
Happiness
6.6 / 10
World Happiness, 2025
Safe drinking water
97%
of population, 2024
Homicide rate
0.6
per 100k, 2023
Road deaths
5.3
per 100k/yr, 2019
Income group
High
World Bank
English
Moderate
EF EPI 513
Religion
Christian 81%unaffiliated 13%Muslim 5%other 1%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Trieste (45.6495°, 13.7768°, elevation 2 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).