Guidonia Montecelio in Summer
In summer (June, July and August), Guidonia Montecelio sees average daytime highs around 29°C and overnight lows near 17°C, with 102 mm of rain over about 18 wet days across the season. It is the warmest season of the year and the driest season of the year.
Over the season highs climb from about 25°C in early June to 29°C by late August. The sky is clear or mostly clear about 72% of the time across summer, and the air most often feels humid.
Summer is Guidonia Montecelio's best season of the year to visit on our travel score. For the whole year in context, see Guidonia Montecelio's year-round climate.
- Avg daytime high
- 29°C
- warmest season of the year
- Avg overnight low
- 17°C
- Rainfall
- 102 mm
- 18 wet days
- Avg wind
- 6 km/h
- Travel score
- 6.3
- best season of the year
- Months
- Jun · Jul · Aug
Temperature in Guidonia Montecelio in Summer
Over the season highs climb from about 25°C in early June to 29°C by late August.
A typical summer day in Guidonia Montecelio reaches about 29°C and drops to 17°C overnight. The warmest of the three months is August, the coolest June.
How summer really feels in Guidonia Montecelio
Once humidity and wind are folded in, summer brings about 0 days that feel above 32°C and 0 that feel at or below 0°C.
summer sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Guidonia Montecelio weather by month
How the three summer months (June, July and August) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 10° / 2° | 69 | 8.6 | 0.6 | 9.3 | 2.6 |
| Feb | 12° / 2° | 76 | 9.3 | 0.9 | 10.3 | 3.0 |
| Mar | 15° / 5° | 84 | 9.9 | 0.5 | 11.7 | 4.5 |
| Apr | 18° / 7° | 94 | 12.2 | 0.1 | 13.1 | 5.5 |
| May | 22° / 11° | 77 | 10.4 | 0 | 14.3 | 6.8 |
| Jun | 27° / 15° | 46 | 7.3 | 0 | 15 | 7.1 |
| Jul | 30° / 18° | 28 | 4.8 | 0 | 14.7 | 6.1 |
| Aug | 30° / 18° | 28 | 5.5 | 0 | 13.7 | 5.8 |
| Sep | 25° / 15° | 85 | 9.4 | 0 | 12.3 | 7.1 |
| Oct | 21° / 11° | 113 | 10.4 | 0 | 10.9 | 6.5 |
| Nov | 15° / 7° | 132 | 12.4 | 0 | 9.6 | 4.5 |
| Dec | 11° / 3° | 104 | 10.4 | 0.3 | 9 | 2.9 |
Cloud cover in Summer
The sky is clear or mostly clear about 72% of the time across summer.
Chance of precipitation in Summer
Guidonia Montecelio gets around 102 mm of rain over 18 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels humid — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 6 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 14 h 48 min in early June to 13 hours by late August. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 6.7 kWh/m².
Is summer a good time to visit Guidonia Montecelio?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a reasonable time to visit Guidonia Montecelio for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Guidonia Montecelio in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Guidonia Montecelio sees daytime highs around 29°C and nights near 17°C. Pack light clothes and sun protection. About 18 days see rain.
Sea temperature near Guidonia Montecelio in Summer
The nearest coast averages about 24°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 50 km away) is warmest in August at about 26°C and coldest in February near 14°C.
It's comfortable for a long swim from May 31 to Nov 1 — about 5.1 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 15 | 14 | 14 | 15 | 18 | 22 | 25 | 26 | 24 | 21 | 19 | 16 |
| Comfort | Bracing | Bracing | Bracing | Cool | Cool | Refreshing | Warm | Warm | Refreshing | Refreshing | Cool | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 15 | Bracing |
| Feb | 14 | Bracing |
| Mar | 14 | Bracing |
| Apr | 15 | Cool |
| May | 18 | Cool |
| Jun | 22 | Refreshing |
| Jul | 25 | Warm |
| Aug | 26 | Warm |
| Sep | 24 | Refreshing |
| Oct | 21 | Refreshing |
| Nov | 19 | Cool |
| Dec | 16 | Cool |
UV index in Guidonia Montecelio in Summer
Clear-sky midday UV across summer averages around 9 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Guidonia Montecelio peaks around July 15 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 3 | 5 | 4 | 7 | 9 | 10 | 8 | 6 | 3 | 2 | 1 |
| Level | Low | Moderate | High | Moderate | High | Very high | Very high | Very high | High | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 3 | Moderate |
| Mar | 5 | High |
| Apr | 4 | Moderate |
| May | 7 | High |
| Jun | 9 | Very high |
| Jul | 10 | Very high |
| Aug | 8 | Very high |
| Sep | 6 | High |
| Oct | 3 | Moderate |
| Nov | 2 | Moderate |
| Dec | 1 | Low |
Air quality in Guidonia Montecelio in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Guidonia Montecelio is worst in April — around 17 µg/m³ PM2.5 (moderate), and holds fairly steady the rest of the year.
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 15 | 15 | 17 | 17 | 15 | 14 | 12 | 13 | 11 | 12 | 12 | 13 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Moderate | Good | Moderate | Good | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 15 | Moderate |
| Feb | 15 | Moderate |
| Mar | 17 | Moderate |
| Apr | 17 | Moderate |
| May | 15 | Moderate |
| Jun | 14 | Moderate |
| Jul | 12 | Good |
| Aug | 13 | Moderate |
| Sep | 11 | Good |
| Oct | 12 | Moderate |
| Nov | 12 | Good |
| Dec | 13 | Moderate |
Where is Guidonia Montecelio?
Guidonia Montecelio sits at 42.0°N, 12.7°E, 92 m above sea level, in Italy. The nearest listed city is Guidonia, 0.0 km away.
Topography around Guidonia Montecelio
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Guidonia Montecelio.
Within 3 km, the terrain around Guidonia Montecelio has significant variations in elevation — a maximum elevation change of 308 m around an average of 105 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,260 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,441 m.
The land around Guidonia Montecelio is covered by cropland (31%) and trees (26%) within 3 km, trees (53%) and cropland (21%) within 16 km, and trees (51%) within 80 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
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 Guidonia Montecelio (41.9936°, 12.7224°, elevation 92 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.