San Sebastiano weather in September

In September, San Sebastiano sees average daytime highs of 19°C and overnight lows near 12°C, with 129 mm of precipitation across 14.2 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 21°C in the first days to 17°C by the end. The sky is clear or mostly clear about 34% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 06 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is San Sebastiano's 6th-clearest and 7th-windiest month. For the whole year in context, see San Sebastiano's year-round climate.

Daytime high
19°
4th warmest
Overnight low
12°
9th coldest
Precipitation
129 mm
14.2 wet days
Daylight
12 h 18 min
6:04 AM – 6:23 PM
Cloud cover
55%
6th clearest
Wind
4 km/h
7th windiest
Solar energy
3.75 kWh/m²
Travel score
5.5
out of 10

San Sebastiano is settlement in Lumezzane, Italy.

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 21°C in the first days to 17°C by the end.

A typical September day in San Sebastiano reaches about 19°C in the afternoon and slips back to 12°C overnight — a 7°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, September runs about 4°C cooler than August and about 5°C warmer than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
12114
22114
32114
42113
52113
62013
72013
82013
92013
102013
112013
121912
131912
141912
151912
161912
171912
181812
191812
201812
211811
221811
231811
241811
251711
261711
271711
281711
291710
301710

How September really feels in San Sebastiano

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.

San Sebastiano 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
Jan / -3°557.15.58.90.0
Feb / -2°607.76.210.10.3
Mar10° / 8110.75.311.62.1
Apr13° / 11816.63.513.33.1
May17° / 13820.10.314.74.4
Jun21° / 13°14118.7015.45.2
Jul23° / 15°12617.8015.15.9
Aug23° / 15°12616.7013.96.0
Sep19° / 12°12914.20.112.35.5
Oct14° / 13912.30.710.73.9
Nov / 13711.53.49.31.6
Dec / -1°798.35.58.60.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 34% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 23% of September, with mostly cloudy or overcast conditions the remaining 44%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16436
26436
36436
46436
56337
66337
76337
86337
96238
106139
116139
126040
135941
145842
155743
165644
175545
185446
195446
205248
215248
225149
235149
245050
255050
265050
274753
284753
294654
304654

Chance of precipitation in September

Any precipitation

San Sebastiano gets around 129 mm of rain and snow over 14.2 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 48% and peaks near 54% on the wettest days, and about 0 day brings snow. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
154
254
353
452
552
651
750
849
949
1048
1148
1247
1347
1447
1546
1646
1746
1846
1946
2046
2146
2246
2346
2445
2545
2645
2745
2846
2946
3046

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the dry band about 61% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
1374122
2394120
3414018
4434017
5454015
6474014
7483912
8503911
9513910
1052399
1154388
1255387
1356377
1457376
1559365
1661354
1762344
1864333
1966313
2067303
2169292
2270282
2373261
2474251
2576231
2677221
2778211
2881190
2982180
3083170

Wind in September

Winds average 4 km/h in September.

Across September, daily wind ranges from about 4 km/h on the calmest days to 4 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 06 min at the start of September to 11 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 96 minutes over September. Sunrise moves from 5:45 AM to 6:22 AM, and sunset from 6:53 PM to 5:55 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.15:456:53
213.15:466:51
313.05:476:49
413.05:496:47
512.95:506:45
612.95:516:43
712.85:526:41
812.85:546:39
912.75:556:37
1012.65:566:35
1112.65:576:33
1212.55:596:31
1312.56:006:29
1412.46:016:27
1512.46:036:25
1612.36:046:23
1712.36:056:21
1812.26:066:19
1912.26:086:17
2012.16:096:15
2112.06:106:13
2212.06:116:11
2311.96:136:09
2411.96:146:07
2511.86:156:05
2611.86:176:03
2711.76:186:01
2811.76:195:59
2911.66:215:57
3011.56:225:55

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.75 kWh/m².

For context, solar energy here swings from a low near 1.34 kWh/m² to a high of 5.84 kWh/m² in July across the year — September's 3.75 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.4Bright
24.4Bright
34.3Bright
44.3Bright
54.2Bright
64.2Bright
74.2Bright
84.1Bright
94.0Bright
104.0Bright
114.0Moderate
123.9Moderate
133.9Moderate
143.8Moderate
153.8Moderate
163.7Moderate
173.7Moderate
183.6Moderate
193.6Moderate
203.5Moderate
213.5Moderate
223.4Moderate
233.4Moderate
243.3Moderate
253.3Moderate
263.2Moderate
273.2Moderate
283.1Moderate
293.1Moderate
303.0Moderate
Planning a trip in September

Is September a good time to visit San Sebastiano?

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

5.5
Sightseeing
3rd-best month of the year
2.3
Beach & pool
4th-best month of the year

September is a reasonable time to visit San Sebastiano for sightseeing.

What to pack for San Sebastiano in September

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

In September, San Sebastiano sees daytime highs around 19°C and nights near 12°C. Pack rain gear. About 14 days see rain.

rain gear

UV index in San Sebastiano in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in San Sebastiano peaks around July 15 at about 8 (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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 15UV 8Dec 22UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar4Moderate
Apr7High
May7Very high
Jun8Very high
Jul8Very high
Aug7High
Sep5Moderate
Oct3Moderate
Nov2Low
Dec1Low

Air quality in San Sebastiano 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 San Sebastiano is worst in March — around 21 µg/m³ PM2.5 (moderate), and holds fairly steady the rest of the year.

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 2021 µg/m³Nov 1514 µg/m³
PM2.5 (µg/m³)Level
Jan18Moderate
Feb17Moderate
Mar21Moderate
Apr20Moderate
May17Moderate
Jun19Moderate
Jul16Moderate
Aug14Moderate
Sep14Moderate
Oct14Moderate
Nov13Moderate
Dec15Moderate
Location & terrain

Where is San Sebastiano?

San Sebastiano sits at 45.7°N, 10.3°E, 460 m above sea level, in Italy. The nearest listed city is Lumezzane, 1.0 km away.

Topography around San Sebastiano

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

Within 3 km, the terrain around San Sebastiano has large variations in elevation — a maximum elevation change of 1,044 m around an average of 762 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,830 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,556 m.

The land around San Sebastiano is covered by trees (83%) within 3 km, trees (72%) within 16 km, and trees (40%), cropland (27%) and grassland (20%) within 80 km.

3 km
1,044 m
16 km
1,830 m
80 km
3,556 m
treesgrasslandcroplandartificial surfacesbare terrainsnow and icewatermoss and lichen
September weather nearby: Lumezzane 1.0 km · Brescia 13 km · Ghedi 28 km · Chiari 29 km · Montichiari 29 km · Palazzolo sull'Oglio 29 km · Desenzano del Garda 30 km · Castiglione delle Stiviere 34 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 San Sebastiano (45.6519°, 10.2568°, elevation 460 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. 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).