Isernia in Summer
In summer (June, July and August), Isernia sees average daytime highs around 25°C and overnight lows near 15°C, with 141 mm of rain over about 27 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 22°C in early June to 25°C by late August. The sky is clear or mostly clear about 61% of the time across summer, and the air most often feels comfortable.
Summer is Isernia's best season of the year to visit on our travel score. For the whole year in context, see Isernia's year-round climate.
- Avg daytime high
- 25°C
- warmest season of the year
- Avg overnight low
- 15°C
- Rainfall
- 141 mm
- 27 wet days
- Avg wind
- 5 km/h
- Travel score
- 7.3
- best season of the year
- Months
- Jun · Jul · Aug
Temperature in Isernia in Summer
Over the season highs climb from about 22°C in early June to 25°C by late August.
A typical summer day in Isernia reaches about 25°C and drops to 15°C overnight. The warmest of the three months is August, the coolest June.
How summer really feels in Isernia
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.
Isernia 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 | 8° / 0° | 88 | 10.6 | 2.4 | 9.3 | 1.3 |
| Feb | 9° / 1° | 92 | 11.1 | 2.8 | 10.3 | 1.6 |
| Mar | 12° / 3° | 106 | 12.9 | 2.2 | 11.7 | 2.9 |
| Apr | 15° / 6° | 108 | 14.2 | 0.3 | 13.1 | 4.1 |
| May | 19° / 10° | 89 | 12.9 | 0 | 14.3 | 5.8 |
| Jun | 24° / 14° | 62 | 10.2 | 0 | 15 | 7.1 |
| Jul | 26° / 16° | 43 | 8.3 | 0 | 14.7 | 7.4 |
| Aug | 27° / 16° | 36 | 8.3 | 0 | 13.7 | 7.3 |
| Sep | 22° / 13° | 79 | 10.4 | 0 | 12.3 | 6.8 |
| Oct | 18° / 9° | 111 | 10.4 | 0.1 | 10.9 | 5.8 |
| Nov | 13° / 5° | 150 | 12.5 | 0.8 | 9.7 | 3.4 |
| Dec | 9° / 2° | 121 | 12.4 | 2.4 | 9 | 1.7 |
Cloud cover in Summer
The sky is clear or mostly clear about 61% of the time across summer.
Chance of precipitation in Summer
Isernia gets around 141 mm of rain over 27 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels comfortable — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 5 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 6.5 kWh/m².
Is summer a good time to visit Isernia?
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 one of the better times to visit Isernia for general sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Isernia in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Isernia sees daytime highs around 25°C and nights near 15°C. Pack sun protection. Worth having: light clothes and rain gear. About 27 days see rain.
Sea temperature near Isernia 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 60 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 27 to Nov 5 — about 5.4 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 | 16 | 19 | 22 | 25 | 26 | 24 | 22 | 19 | 17 |
| Comfort | Bracing | Bracing | Bracing | Cool | Cool | Refreshing | Warm | Warm | Warm | Refreshing | Cool | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 15 | Bracing |
| Feb | 14 | Bracing |
| Mar | 14 | Bracing |
| Apr | 16 | Cool |
| May | 19 | Cool |
| Jun | 22 | Refreshing |
| Jul | 25 | Warm |
| Aug | 26 | Warm |
| Sep | 24 | Warm |
| Oct | 22 | Refreshing |
| Nov | 19 | Cool |
| Dec | 17 | Cool |
UV index in Isernia 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 Isernia peaks around July 15 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 3 | 5 | 5 | 7 | 9 | 10 | 9 | 6 | 4 | 2 | 1 |
| Level | Low | Moderate | High | Moderate | Very high | Very high | Extreme | Very high | High | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Low |
| Feb | 3 | Moderate |
| Mar | 5 | High |
| Apr | 5 | Moderate |
| May | 7 | Very high |
| Jun | 9 | Very high |
| Jul | 10 | Extreme |
| Aug | 9 | Very high |
| Sep | 6 | High |
| Oct | 4 | Moderate |
| Nov | 2 | Moderate |
| Dec | 1 | Low |
Air quality in Isernia 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 Isernia is worst in April — around 22 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) | 19 | 20 | 21 | 22 | 18 | 16 | 16 | 16 | 14 | 16 | 16 | 17 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 19 | Moderate |
| Feb | 20 | Moderate |
| Mar | 21 | Moderate |
| Apr | 22 | Moderate |
| May | 18 | Moderate |
| Jun | 16 | Moderate |
| Jul | 16 | Moderate |
| Aug | 16 | Moderate |
| Sep | 14 | Moderate |
| Oct | 16 | Moderate |
| Nov | 16 | Moderate |
| Dec | 17 | Moderate |
Where is Isernia?
Isernia sits at 41.6°N, 14.2°E, 423 m above sea level, in Italy. The nearest listed city is Cassino, 36 km away.
Topography around Isernia
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Isernia.
Within 3 km, the terrain around Isernia has significant variations in elevation — a maximum elevation change of 398 m around an average of 468 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,340 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,771 m.
The land around Isernia is covered by trees (63%) within 3 km, trees (72%) and grassland (22%) within 16 km, and trees (51%) and cropland (21%) 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 Isernia (41.596°, 14.234°, elevation 423 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.