Isernia weather in May

In May, Isernia sees average daytime highs of 19°C and overnight lows near 10°C, with 89 mm of rain across 12.9 wet days and about 14.3 hours of daylight. It is the 5th-warmest and 7th-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 30% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 48 min at the start of May to 14 h 48 min by month's end. Set against the rest of the year, May is Isernia's 6th-clearest and 7th-windiest month. For the whole year in context, see Isernia's year-round climate.

Daytime high
19°
5th warmest
Overnight low
10°
8th coldest
Rainfall
89 mm
12.9 wet days
Daylight
14 h 18 min
4:49 AM – 7:09 PM
Cloud cover
56%
6th clearest
Wind
5 km/h
7th windiest
Solar energy
6.11 kWh/m²
Travel score
5.8
out of 10
Air quality
Excellent
PM10 11.9 µg/m³ · 2018

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 Isernia reaches about 19°C in the afternoon and slips back to 10°C overnight — a 10°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 4°C warmer than April and about 4°C cooler than June.

10°20°30°151015202531
Avg high (°C)Avg low (°C)
1178
2178
3188
4188
5189
6189
7189
8189
9189
10199
11199
12199
13199
14199
151910
161910
171910
181910
192010
202010
212010
222010
232010
242010
252011
262011
272111
282111
292111
302111
312111

How May really feels in Isernia

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.

Isernia weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 8810.62.49.31.3
Feb / 9211.12.810.31.6
Mar12° / 10612.92.211.72.9
Apr15° / 10814.20.313.14.1
May19° / 10°8912.9014.35.8
Jun24° / 14°6210.20157.1
Jul26° / 16°438.3014.77.4
Aug27° / 16°368.3013.77.3
Sep22° / 13°7910.4012.36.8
Oct18° / 11110.40.110.95.8
Nov13° / 15012.50.89.73.4
Dec / 12112.42.491.7

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 30% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 23% of May, with mostly cloudy or overcast conditions the remaining 47%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14555
24555
34555
44753
54852
64852
75050
85050
95050
105149
115248
125149
135248
145248
155347
165347
175545
185545
195545
205644
215644
225644
235842
245842
255842
265941
275941
285941
295941
305941
315941

Chance of precipitation in May

Any precipitation

Isernia gets around 89 mm of rain over 12.9 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 42% and peaks near 47% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
147
247
347
446
546
645
745
844
943
1043
1142
1241
1341
1440
1540
1639
1739
1839
1939
2039
2139
2239
2339
2440
2540
2640
2741
2841
2941
3042
3142

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 85% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
19820
29820
39730
49730
59640
69550
79550
89460
99370
109370
119280
129190
139190
1490100
1589110
1689110
1788120
1887130
1984151
2083161
2182171
2281181
2379201
2477221
2576231
2674251
2771272
2869292
2967312
3065332
3163352

Wind in May

Winds average 5 km/h in May.

Across May, daily wind ranges from about 5 km/h on the calmest days to 5 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 48 min at the start of May to 14 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 60 minutes over May. Sunrise moves from 5:07 AM to 4:38 AM, and sunset from 6:53 PM to 7:23 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.85:076:53
213.85:066:54
313.95:046:56
413.95:036:57
513.95:026:58
614.05:016:59
714.04:597:00
814.04:587:01
914.14:577:02
1014.14:567:03
1114.24:557:04
1214.24:537:05
1314.24:527:06
1414.34:517:07
1514.34:507:08
1614.34:497:09
1714.44:487:10
1814.44:477:11
1914.44:467:12
2014.54:467:13
2114.54:457:14
2214.54:447:15
2314.64:437:16
2414.64:427:17
2514.64:417:18
2614.64:417:19
2714.74:407:20
2814.74:397:21
2914.74:397:22
3014.74:387:22
3114.84:387:23

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 6.11 kWh/m².

For context, solar energy here swings from a low near 1.66 kWh/m² to a high of 6.8 kWh/m² in July across the year — May's 6.11 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.6Bright
25.7Bright
35.7Bright
45.7Bright
55.8Bright
65.8Bright
75.8Bright
85.9Bright
95.9Bright
105.9Bright
116.0Bright
126.0Bright
136.0Intense
146.0Intense
156.1Intense
166.1Intense
176.1Intense
186.2Intense
196.2Intense
206.2Intense
216.2Intense
226.3Intense
236.3Intense
246.3Intense
256.3Intense
266.3Intense
276.3Intense
286.4Intense
296.4Intense
306.4Intense
316.4Intense
Planning a trip in May

Is May a good time to visit Isernia?

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 Isernia for sightseeing.

What to pack for Isernia in May

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

In May, Isernia sees daytime highs around 19°C and nights near 10°C. Pack sun protection. Worth having: rain gear. About 13 days see rain.

sun protectionrain gear

Sea temperature near Isernia in May

The nearest coast averages about 19°C in May — 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.

15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan15Bracing
Feb14Bracing
Mar14Bracing
Apr16Cool
May19Cool
Jun22Refreshing
Jul25Warm
Aug26Warm
Sep24Warm
Oct22Refreshing
Nov19Cool
Dec17Cool

UV index in Isernia 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 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 15UV 10Dec 21UV 1
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5High
Apr5Moderate
May7Very high
Jun9Very high
Jul10Extreme
Aug9Very high
Sep6High
Oct4Moderate
Nov2Moderate
Dec1Low

Air quality in Isernia 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 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).

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateApr 1021 µg/m³Sep 1714 µg/m³
PM2.5 (µg/m³)Level
Jan19Moderate
Feb20Moderate
Mar21Moderate
Apr22Moderate
May18Moderate
Jun16Moderate
Jul16Moderate
Aug16Moderate
Sep14Moderate
Oct16Moderate
Nov16Moderate
Dec17Moderate
Location & terrain

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.

3 km
398 m
16 km
1,340 m
80 km
2,771 m
treesshrubsgrasslandcroplandartificial surfaceswater
May weather nearby: Cassino 36 km · Campobasso 36 km · Sora 53 km · Capua 55 km · Minturno 55 km · Sulmona 57 km · Santa Maria Capua Vetere 57 km · Caserta 59 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 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. 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).