Mentana weather in September

In September, Mentana sees average daytime highs of 25°C and overnight lows near 15°C, with 85 mm of rain across 9.4 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 28°C in the first days to 23°C by the end. The sky is clear or mostly clear about 52% of the time in September, and the air most often feels comfortable.

Daylight stretches from about 13 hours at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Mentana's 4th-clearest and 9th-windiest month. For the whole year in context, see Mentana's year-round climate.

Daytime high
25°
4th warmest
Overnight low
15°
9th coldest
Rainfall
85 mm
9.4 wet days
Daylight
12 h 18 min
5:55 AM – 6:12 PM
Cloud cover
42%
4th clearest
Wind
6 km/h
9th windiest
Solar energy
4.49 kWh/m²
Travel score
7.1
out of 10

Mentana is chief town of the homonym municipality.

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 28°C in the first days to 23°C by the end.

A typical September day in Mentana reaches about 25°C in the afternoon and slips back to 15°C overnight — a 11°C spread between the day's warmth and the night's chill. On most days the high lands between 21°C and 29°C. Set against its neighbours, September runs about 5°C cooler than August and about 5°C warmer than October.

10°20°30°151015202530
Avg high (°C)Avg low (°C)
12817
22817
32816
42716
52716
62716
72716
82716
92616
102615
112615
122615
132615
142615
152515
162515
172515
182514
192514
202414
212414
222414
232414
242414
252414
262313
272313
282313
292313
302313

How September really feels in Mentana

Once humidity and wind are folded in, September 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

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

Mentana weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan10° / 698.60.69.32.6
Feb12° / 769.30.910.33.0
Mar15° / 849.90.511.74.5
Apr18° / 9412.20.113.15.5
May22° / 11°7710.4014.36.8
Jun27° / 15°467.30157.1
Jul30° / 18°284.8014.76.1
Aug30° / 18°285.5013.75.8
Sep25° / 15°859.4012.37.1
Oct21° / 11°11310.4010.96.5
Nov15° / 13212.409.64.5
Dec11° / 10410.40.392.9

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 52% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 20% of September, with mostly cloudy or overcast conditions the remaining 28%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
18218
28119
38020
47921
57822
67723
77624
87525
97525
107426
117327
127228
137228
147129
157129
167030
177030
187030
196931
206832
216832
226832
236832
246733
256733
266733
276634
286634
296634
306535

Chance of precipitation in September

Any precipitation

Mentana gets around 85 mm of rain over 9.4 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 32% and peaks near 34% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
127
228
328
429
529
630
730
831
931
1031
1132
1232
1332
1433
1533
1633
1734
1834
1934
2034
2134
2233
2333
2433
2533
2633
2733
2833
2933
3033

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the comfortable band about 39% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
11933408
22034397
32135377
42236366
52337355
62438345
72439334
82539324
92540314
102640313
112640303
122740303
132740303
142840293
152940293
163040283
173140273
183240263
193340243
203539233
213639222
223839212
233939202
244039192
254139182
264339171
274439161
284539151
294639141
304738141

Wind in September

Winds average 6 km/h in September.

Across September, daily wind ranges from about 6 km/h on the calmest days to 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 hours at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 84 minutes over September. Sunrise moves from 5:39 AM to 6:11 AM, and sunset from 6:39 PM to 5:47 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.05:396:39
212.95:406:37
312.95:416:35
412.95:436:34
512.85:446:32
612.85:456:30
712.75:466:28
812.75:476:27
912.65:486:25
1012.65:496:23
1112.55:506:21
1212.55:516:19
1312.45:526:18
1412.45:536:16
1512.35:546:14
1612.35:556:12
1712.25:566:10
1812.25:586:08
1912.15:596:07
2012.16:006:05
2112.06:016:03
2212.06:026:01
2311.96:035:59
2411.96:045:58
2511.86:055:56
2611.86:065:54
2711.76:075:52
2811.76:085:50
2911.66:105:49
3011.66:115:47

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.49 kWh/m².

For context, solar energy here swings from a low near 1.61 kWh/m² to a high of 7 kWh/m² in July across the year — September's 4.49 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.3Bright
25.3Bright
35.2Bright
45.1Bright
55.1Bright
65.0Bright
75.0Bright
84.9Bright
94.8Bright
104.8Bright
114.7Bright
124.7Bright
134.6Bright
144.5Bright
154.5Bright
164.4Bright
174.4Bright
184.3Bright
194.3Bright
204.2Bright
214.2Bright
224.1Bright
234.1Bright
244.0Bright
254.0Moderate
263.9Moderate
273.9Moderate
283.8Moderate
293.8Moderate
303.7Moderate
Planning a trip in September

Is September a good time to visit Mentana?

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

7.1
Sightseeing
1st-best month of the year
6.4
Beach & pool
4th-best month of the year

September is one of the better times to visit Mentana for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Mentana in September

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

In September, Mentana sees daytime highs around 25°C and nights near 15°C. Worth packing: light clothes and rain gear. About 9 days see rain.

light clothesrain gear

Sea temperature near Mentana in September

The nearest coast averages about 24°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 46 km away) is warmest in August at about 25°C and coldest in February near 14°C.

It's comfortable for a long swim from Jun 1 to Oct 31 — about 5 months when the water holds above 20°C.

15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan15Bracing
Feb14Bracing
Mar14Bracing
Apr15Cool
May18Cool
Jun22Refreshing
Jul25Warm
Aug25Warm
Sep24Refreshing
Oct21Refreshing
Nov19Cool
Dec16Cool

UV index in Mentana in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Mentana 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateVery highHighModerateLowJul 15UV 10Dec 22UV 1
UV index (midday)Level
Jan1Low
Feb3Moderate
Mar5High
Apr4Moderate
May7High
Jun9Very high
Jul10Very high
Aug8Very high
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low

Air quality in Mentana in September

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Mentana 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).

01020JanFebMarAprMayJunJulAugSepOctNovDecModerateModerateGoodModerateModerateApr 1117 µg/m³Sep 1812 µg/m³
PM2.5 (µg/m³)Level
Jan15Moderate
Feb15Moderate
Mar17Moderate
Apr17Moderate
May15Moderate
Jun14Moderate
Jul12Good
Aug13Moderate
Sep11Good
Oct12Moderate
Nov12Good
Dec13Moderate
Location & terrain

Where is Mentana?

Mentana sits at 42.0°N, 12.6°E, 150 m above sea level, in Italy. The nearest listed city is Monterotondo, 3.0 km away.

Topography around Mentana

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

Within 3 km, the terrain around Mentana has only modest variations in elevation — a maximum elevation change of 156 m around an average of 129 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,252 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,430 m.

The land around Mentana is covered by trees (53%) within 3 km, trees (46%) and cropland (24%) within 16 km, and trees (51%) within 80 km.

3 km
156 m
16 km
1,252 m
80 km
2,430 m
treesshrubsgrasslandcroplandartificial surfaceswater
September weather nearby: Monterotondo 3.0 km · Tor Lupara 5.0 km · Guidonia 8.0 km · Guidonia Montecelio 8.0 km · Villanova 12 km · Casal de' Pazzi 14 km · Villa Adriana 14 km · Tivoli 16 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 Mentana (42.0354°, 12.6441°, elevation 150 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).