St. Moritz weather in September

In September, St. Moritz sees average daytime highs of 10°C and overnight lows near 1°C, with 108 mm of precipitation across 13.4 wet days and about 12.4 hours of daylight. It is the 4th-warmest and 7th-wettest month of the year here.

Highs ease over the month, from about 12°C in the first days to 8°C by the end. The sky is clear or mostly clear about 22% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 12 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is St. Moritz's 7th-clearest and 10th-windiest month. For the whole year in context, see St. Moritz's year-round climate.

Daytime high
10°
4th warmest
Overnight low
9th coldest
Precipitation
108 mm
13.4 wet days
Daylight
12 h 18 min
6:05 AM – 6:25 PM
Cloud cover
65%
7th clearest
Wind
5 km/h
10th windiest
Solar energy
3.9 kWh/m²
Travel score
2.0
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 12°C in the first days to 8°C by the end.

A typical September day in St. Moritz reaches about 10°C in the afternoon and slips back to 1°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 4°C and 15°C. Set against its neighbours, September runs about 4°C cooler than August and about 5°C warmer than October.

-5°10°15°20°151015202530
Avg high (°C)Avg low (°C)
1123
2123
3123
4123
5123
6113
7112
8112
9112
10112
11112
12112
13102
14102
15101
16101
17101
18101
19101
2091
2191
2291
2391
2490
2590
2690
2780
2880
2980
3080

How September really feels in St. Moritz

Once humidity and wind are folded in, September averages 0 days that feel above 32°C and 17 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
17
wind chill below the day's low

The story in September is cold — wind chill drags the overnight "feels like" below the raw low.

St. Moritz weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-7° / -15°751112.68.80.0
Feb-5° / -14°6110.411.6100.0
Mar-1° / -10°741213.711.60.0
Apr / -5°10614.714.113.30.0
May / -1°13318.510.614.80.7
Jun12° / 15619.13.715.52.6
Jul14° / 15819.41.215.23.4
Aug14° / 16118.21.4143.3
Sep10° / 10813.44.112.42.0
Oct / -2°11911.98.110.70.4
Nov-1° / -8°14313.714.19.20.0
Dec-6° / -13°8312.213.48.40.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 62%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14258
24258
34159
44159
54258
64060
73961
84060
93961
103961
113862
123862
133862
143862
153862
163862
173862
183862
193862
203862
213763
223763
233763
243763
253763
263763
273763
283664
293664
303664

Chance of precipitation in September

Any precipitationSnow

St. Moritz gets around 108 mm of rain and snow over 13.4 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 46% and peaks near 53% on the wettest days, and about 4 days bring snow. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)Snow chance (%)
15311
25211
35211
45112
55112
65012
75013
85013
94913
104914
114814
124814
134714
144615
154615
164515
174415
184415
194315
204215
214215
224115
234115
244115
254115
264116
274116
284117
294117
304118

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 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100

Wind in September

Winds average 5 km/h in September.

Across September, 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.

0246810151015202530
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

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 12 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 102 minutes over September. Sunrise moves from 5:45 AM to 6:24 AM, and sunset from 6:55 PM to 5:56 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.25:456:55
213.15:476:53
313.15:486:51
413.05:496:49
512.95:516:47
612.95:526:45
712.85:536:43
812.85:556:41
912.75:566:39
1012.75:576:37
1112.65:596:35
1212.66:006:33
1312.56:016:31
1412.46:036:29
1512.46:046:27
1612.36:056:25
1712.36:076:23
1812.26:086:21
1912.26:096:19
2012.16:106:16
2112.06:126:14
2212.06:136:12
2311.96:146:10
2411.96:166:08
2511.86:176:06
2611.86:196:04
2711.76:206:02
2811.66:216:00
2911.66:235:58
3011.56:245:56

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.9 kWh/m².

For context, solar energy here swings from a low near 1.49 kWh/m² to a high of 5.98 kWh/m² in May across the year — September's 3.9 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.4Bright
24.4Bright
34.4Bright
44.3Bright
54.3Bright
64.3Bright
74.2Bright
84.2Bright
94.2Bright
104.1Bright
114.1Bright
124.0Bright
134.0Moderate
144.0Moderate
153.9Moderate
163.9Moderate
173.8Moderate
183.8Moderate
193.8Moderate
203.7Moderate
213.7Moderate
223.6Moderate
233.6Moderate
243.6Moderate
253.5Moderate
263.5Moderate
273.4Moderate
283.4Moderate
293.4Moderate
303.3Moderate
Planning a trip in September

Is September a good time to visit St. Moritz?

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

2.0
Sightseeing
4th-best month of the year
Beach & pool
never really warm enough

September is a weaker month for outdoor sightseeing in St. Moritz.

What to pack for St. Moritz in September

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

In September, St. Moritz sees daytime highs around 10°C and nights near 1°C. Pack a warm layer and rain gear. About 13 days see rain.

a warm layerrain gear

UV index in St. Moritz 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 St. Moritz peaks around July 15 at about 9 (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 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 15UV 9Dec 22UV 1
UV index (midday)Level
Jan1Low
Feb3Moderate
Mar6High
Apr8Very high
May9Very high
Jun9Very high
Jul10Very high
Aug8Very high
Sep6High
Oct4Moderate
Nov2Low
Dec1Low
Location & terrain

Where is St. Moritz?

St. Moritz sits at 46.5°N, 9.8°E, 0 m above sea level, in Switzerland. The nearest listed city is Davos, 34 km away.

DavosSondrioChurBellinzonaBludenzVaduzLeccoFeldkirch

Topography around St. Moritz

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

Within 3 km, the terrain around St. Moritz has large variations in elevation — a maximum elevation change of 1,149 m around an average of 2,048 m above sea level; within 16 km, extreme variations in elevation — a maximum elevation change of 2,603 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,753 m.

The land around St. Moritz is covered by trees (43%) and grassland (43%) within 3 km, grassland (37%) and bare terrain (21%) within 16 km, and trees (43%) and grassland (35%) within 80 km.

3 km
1,149 m
16 km
2,603 m
80 km
3,753 m
treesgrasslandartificial surfacesbare terrainsnow and icewatermoss and lichen
September weather nearby: Davos 34 km · Sondrio 37 km · Chur 46 km · Bellinzona 72 km · Bludenz 73 km · Vaduz 75 km · Lecco 79 km · Feldkirch 84 km

Switzerland travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / J
230 V · 50 Hz
Prices
≈ 112% of US
price level, 2025
GDP per capita
$114,769
2025
Happiness
7.0 / 10
World Happiness, 2025
Safe drinking water
97%
of population, 2024
Homicide rate
0.6
per 100k, 2023
Road deaths
2.2
per 100k/yr, 2019
Income group
High
World Bank
English
High
EF EPI 564
Religion
Roman Catholic 34%none 29%Protestant 23%other Christian 6%

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 St. Moritz (46.4994°, 9.8433°, elevation 0 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).