Interlaken weather in September

In September, Interlaken sees average daytime highs of 15°C and overnight lows near 7°C, with 145 mm of precipitation across 14.4 wet days and about 12.4 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 16°C in the first days to 13°C by the end. The sky is clear or mostly clear about 29% 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 Interlaken's 3rd-clearest and 8th-windiest month. For the whole year in context, see Interlaken's year-round climate.

Daytime high: 15°; 4th warmest
Overnight low: 7°; 9th coldest
Precipitation: 145 mm; 14.4 wet days
Daylight: 12 h 18 min; 6:13 AM – 6:33 PM
Cloud cover: 59%; 3rd clearest
Wind: 5 km/h; 8th windiest
Solar energy: 3.8 kWh/m²
Travel score: 4.0; out of 10

← August Interlaken year-round climate October →Best places to visit in September

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 16°C in the first days to 13°C by the end.

A typical September day in Interlaken reaches about 15°C in the afternoon and slips back to 7°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 10°C and 20°C. Set against its neighbours, September runs about 4°C cooler than August and about 4°C warmer than October.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Avg high (°C)	17	17	17	16	16	16	16	16	16	16	15	15	15	15	15	15	15	14	14	14	14	14	14	14	14	14	13	13	13	13
Avg low (°C)	8	8	8	8	8	8	8	7	7	7	7	7	7	7	7	6	6	6	6	6	6	6	6	6	5	5	5	5	5	5

	Avg high (°C)	Avg low (°C)
1	17	8
2	17	8
3	17	8
4	16	8
5	16	8
6	16	8
7	16	8
8	16	7
9	16	7
10	16	7
11	15	7
12	15	7
13	15	7
14	15	7
15	15	7
16	15	6
17	15	6
18	14	6
19	14	6
20	14	6
21	14	6
22	14	6
23	14	6
24	14	6
25	14	5
26	14	5
27	13	5
28	13	5
29	13	5
30	13	5

How September really feels in Interlaken

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

heat index over the day's high

Days feeling ≤ 0°C

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.

Interlaken 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.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Snow days	Daylight (hours)	Travel score
Jan	0° / -7°	119	13.6	13.3	8.8	0.0
Feb	1° / -6°	106	12.2	11.7	10	0.0
Mar	5° / -3°	114	14.5	12.4	11.6	0.3
Apr	9° / 0°	124	14.8	9.2	13.3	1.6
May	13° / 4°	193	19.1	5.4	14.8	3.0
Jun	17° / 8°	198	19.1	1.4	15.6	4.3
Jul	19° / 10°	211	19.2	0.8	15.3	5.0
Aug	19° / 10°	210	18.3	1	14	5.0
Sep	15° / 7°	145	14.4	2.1	12.4	4.0
Oct	11° / 3°	116	12.1	4.7	10.6	2.6
Nov	5° / -2°	122	13.6	10.7	9.2	0.3
Dec	1° / -5°	125	14.1	13.2	8.4	0.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 29% 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 55%. Skies tend to cloud over as the month goes on.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Clearer (%)	50	50	50	50	49	49	50	50	49	48	48	47	47	47	45	45	45	43	43	43	42	42	42	42	43	42	42	41	41	40
Cloudier (%)	50	50	50	50	51	51	50	50	51	52	52	53	53	53	55	55	55	57	57	57	58	58	58	58	57	58	58	59	59	60

	Clearer (%)	Cloudier (%)
1	50	50
2	50	50
3	50	50
4	50	50
5	49	51
6	49	51
7	50	50
8	50	50
9	49	51
10	48	52
11	48	52
12	47	53
13	47	53
14	47	53
15	45	55
16	45	55
17	45	55
18	43	57
19	43	57
20	43	57
21	42	58
22	42	58
23	42	58
24	42	58
25	43	57
26	42	58
27	42	58
28	41	59
29	41	59
30	40	60

Chance of precipitation in September

Any precipitationSnow

Interlaken gets around 145 mm of rain and snow over 14.4 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 49% and peaks near 52% on the wettest days, and about 2 days bring snow. The odds ease toward the end of the month.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Rain chance (%)	52	52	52	52	51	51	51	51	51	51	50	50	50	50	49	49	49	49	48	48	47	47	46	46	46	46	46	46	46	45
Snow chance (%)	5	5	5	5	5	6	6	6	6	7	7	7	7	8	8	8	8	9	9	9	9	9	9	9	9	9	10	10	11	11

	Rain chance (%)	Snow chance (%)
1	52	5
2	52	5
3	52	5
4	52	5
5	51	5
6	51	6
7	51	6
8	51	6
9	51	6
10	51	7
11	50	7
12	50	7
13	50	7
14	50	8
15	49	8
16	49	8
17	49	8
18	49	9
19	48	9
20	48	9
21	47	9
22	47	9
23	46	9
24	46	9
25	46	9
26	46	9
27	46	10
28	46	10
29	46	11
30	45	11

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 99% of days. It rarely turns muggy — the humid and sticky bands barely register.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Dry (%)	94	95	96	96	97	97	98	98	99	99	99	99	99	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100
Comfortable (%)	6	5	4	4	3	3	2	2	1	1	1	1	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

	Dry (%)	Comfortable (%)
1	94	6
2	95	5
3	96	4
4	96	4
5	97	3
6	97	3
7	98	2
8	98	2
9	99	1
10	99	1
11	99	1
12	99	1
13	99	1
14	100	0
15	100	0
16	100	0
17	100	0
18	100	0
19	100	0
20	100	0
21	100	0
22	100	0
23	100	0
24	100	0
25	100	0
26	100	0
27	100	0
28	100	0
29	100	0
30	100	0

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.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Wind speed (km/h)	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5
Feels	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm

	Wind speed (km/h)	Feels
1	5	calm
2	5	calm
3	5	calm
4	5	calm
5	5	calm
6	5	calm
7	5	calm
8	5	calm
9	5	calm
10	5	calm
11	5	calm
12	5	calm
13	5	calm
14	5	calm
15	5	calm
16	5	calm
17	5	calm
18	5	calm
19	5	calm
20	5	calm
21	5	calm
22	5	calm
23	5	calm
24	5	calm
25	5	calm
26	5	calm
27	5	calm
28	5	calm
29	5	calm
30	5	calm

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 5:53 AM to 6:32 AM, and sunset from 7:03 PM to 6:04 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Daylight (h)	13.2	13.1	13.1	13.0	12.9	12.9	12.8	12.8	12.7	12.7	12.6	12.6	12.5	12.4	12.4	12.3	12.3	12.2	12.2	12.1	12.0	12.0	11.9	11.9	11.8	11.8	11.7	11.6	11.6	11.5
Sunrise (AM)	5:53	5:54	5:56	5:57	5:58	6:00	6:01	6:02	6:04	6:05	6:06	6:08	6:09	6:10	6:12	6:13	6:14	6:16	6:17	6:18	6:20	6:21	6:22	6:24	6:25	6:26	6:28	6:29	6:31	6:32
Sunset (PM)	7:03	7:01	6:59	6:57	6:55	6:53	6:51	6:49	6:47	6:45	6:43	6:41	6:39	6:37	6:35	6:33	6:31	6:29	6:26	6:24	6:22	6:20	6:18	6:16	6:14	6:12	6:10	6:08	6:06	6:04

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	13.2	5:53	7:03
2	13.1	5:54	7:01
3	13.1	5:56	6:59
4	13.0	5:57	6:57
5	12.9	5:58	6:55
6	12.9	6:00	6:53
7	12.8	6:01	6:51
8	12.8	6:02	6:49
9	12.7	6:04	6:47
10	12.7	6:05	6:45
11	12.6	6:06	6:43
12	12.6	6:08	6:41
13	12.5	6:09	6:39
14	12.4	6:10	6:37
15	12.4	6:12	6:35
16	12.3	6:13	6:33
17	12.3	6:14	6:31
18	12.2	6:16	6:29
19	12.2	6:17	6:26
20	12.1	6:18	6:24
21	12.0	6:20	6:22
22	12.0	6:21	6:20
23	11.9	6:22	6:18
24	11.9	6:24	6:16
25	11.8	6:25	6:14
26	11.8	6:26	6:12
27	11.7	6:28	6:10
28	11.6	6:29	6:08
29	11.6	6:31	6:06
30	11.5	6:32	6:04

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.8 kWh/m².

For context, solar energy here swings from a low near 1.22 kWh/m² to a high of 5.71 kWh/m² in June across the year — September's 3.8 kWh/m² falls in the middle.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Solar energy (kWh/m²)	4.3	4.3	4.3	4.2	4.2	4.2	4.1	4.1	4.1	4.0	4.0	3.9	3.9	3.9	3.8	3.8	3.7	3.7	3.6	3.6	3.6	3.5	3.5	3.4	3.4	3.4	3.3	3.3	3.2	3.2
Level	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate

	Solar energy (kWh/m²)	Level
1	4.3	Bright
2	4.3	Bright
3	4.3	Bright
4	4.2	Bright
5	4.2	Bright
6	4.2	Bright
7	4.1	Bright
8	4.1	Bright
9	4.1	Bright
10	4.0	Bright
11	4.0	Moderate
12	3.9	Moderate
13	3.9	Moderate
14	3.9	Moderate
15	3.8	Moderate
16	3.8	Moderate
17	3.7	Moderate
18	3.7	Moderate
19	3.6	Moderate
20	3.6	Moderate
21	3.6	Moderate
22	3.5	Moderate
23	3.5	Moderate
24	3.4	Moderate
25	3.4	Moderate
26	3.4	Moderate
27	3.3	Moderate
28	3.3	Moderate
29	3.2	Moderate
30	3.2	Moderate

Planning a trip in September

Is September a good time to visit Interlaken?

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

4.0

Sightseeing

4th-best month of the year

0.3

Beach & pool

4th-best month of the year

September is a reasonable time to visit Interlaken for sightseeing.

What to pack for Interlaken in September

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

In September, Interlaken sees daytime highs around 15°C and nights near 7°C. Pack rain gear. Worth having: a warm layer. About 14 days see rain.

rain geara warm layer

UV index in Interlaken 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 Interlaken peaks around July 15 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	1	2	5	6	8	8	9	7	5	3	2	1
Level	Low	Moderate	Moderate	High	Very high	Very high	Very high	Very high	High	Moderate	Low	Low

	UV index (midday)	Level
Jan	1	Low
Feb	2	Moderate
Mar	5	Moderate
Apr	6	High
May	8	Very high
Jun	8	Very high
Jul	9	Very high
Aug	7	Very high
Sep	5	High
Oct	3	Moderate
Nov	2	Low
Dec	1	Low

Location & terrain

Where is Interlaken?

Interlaken sits at 46.7°N, 7.9°E, 0 m above sea level, in Switzerland. The nearest listed city is Lauterbrunnen, 11 km away.

Topography around Interlaken

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

Within 3 km, the terrain around Interlaken has large variations in elevation — a maximum elevation change of 1,058 m around an average of 749 m above sea level; within 16 km, extreme variations in elevation — a maximum elevation change of 3,389 m; within 80 km, extreme variations in elevation — a maximum elevation change of 4,230 m.

The land around Interlaken is covered by trees (54%) and grassland (24%) within 3 km, grassland (43%) and trees (42%) within 16 km, and trees (38%) and grassland (37%) within 80 km.

3 km

1,058 m

trees 54%

16 km

3,389 m

grassland 43%

80 km

4,230 m

trees 38%

treesgrasslandcroplandartificial surfacesbare terrainsnow and icewatermoss and lichen

← August Interlaken year-round climate October →Best places to visit in September

September weather nearby: Lauterbrunnen 11 km · Grindelwald 15 km · Thun 20 km · Steffisburg 21 km · Bern 43 km · Köniz 44 km · Burgdorf 45 km · Kriens 50 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

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 Interlaken (46.6839°, 7.8664°, 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).

	Avg high (°C)	Avg low (°C)
1	17	8
2	17	8
3	17	8
4	16	8
5	16	8
6	16	8
7	16	8
8	16	7
9	16	7
10	16	7
11	15	7
12	15	7
13	15	7
14	15	7
15	15	7
16	15	6
17	15	6
18	14	6
19	14	6
20	14	6
21	14	6
22	14	6
23	14	6
24	14	6
25	14	5
26	14	5
27	13	5
28	13	5
29	13	5
30	13	5

	Clearer (%)	Cloudier (%)
1	50	50
2	50	50
3	50	50
4	50	50
5	49	51
6	49	51
7	50	50
8	50	50
9	49	51
10	48	52
11	48	52
12	47	53
13	47	53
14	47	53
15	45	55
16	45	55
17	45	55
18	43	57
19	43	57
20	43	57
21	42	58
22	42	58
23	42	58
24	42	58
25	43	57
26	42	58
27	42	58
28	41	59
29	41	59
30	40	60

	Rain chance (%)	Snow chance (%)
1	52	5
2	52	5
3	52	5
4	52	5
5	51	5
6	51	6
7	51	6
8	51	6
9	51	6
10	51	7
11	50	7
12	50	7
13	50	7
14	50	8
15	49	8
16	49	8
17	49	8
18	49	9
19	48	9
20	48	9
21	47	9
22	47	9
23	46	9
24	46	9
25	46	9
26	46	9
27	46	10
28	46	10
29	46	11
30	45	11

	Dry (%)	Comfortable (%)
1	94	6
2	95	5
3	96	4
4	96	4
5	97	3
6	97	3
7	98	2
8	98	2
9	99	1
10	99	1
11	99	1
12	99	1
13	99	1
14	100	0
15	100	0
16	100	0
17	100	0
18	100	0
19	100	0
20	100	0
21	100	0
22	100	0
23	100	0
24	100	0
25	100	0
26	100	0
27	100	0
28	100	0
29	100	0
30	100	0

	Avg high (°C)	Avg low (°C)
1	17	8
2	17	8
3	17	8
4	16	8
5	16	8
6	16	8
7	16	8
8	16	7
9	16	7
10	16	7
11	15	7
12	15	7
13	15	7
14	15	7
15	15	7
16	15	6
17	15	6
18	14	6
19	14	6
20	14	6
21	14	6
22	14	6
23	14	6
24	14	6
25	14	5
26	14	5
27	13	5
28	13	5
29	13	5
30	13	5

	Clearer (%)	Cloudier (%)
1	50	50
2	50	50
3	50	50
4	50	50
5	49	51
6	49	51
7	50	50
8	50	50
9	49	51
10	48	52
11	48	52
12	47	53
13	47	53
14	47	53
15	45	55
16	45	55
17	45	55
18	43	57
19	43	57
20	43	57
21	42	58
22	42	58
23	42	58
24	42	58
25	43	57
26	42	58
27	42	58
28	41	59
29	41	59
30	40	60

	Rain chance (%)	Snow chance (%)
1	52	5
2	52	5
3	52	5
4	52	5
5	51	5
6	51	6
7	51	6
8	51	6
9	51	6
10	51	7
11	50	7
12	50	7
13	50	7
14	50	8
15	49	8
16	49	8
17	49	8
18	49	9
19	48	9
20	48	9
21	47	9
22	47	9
23	46	9
24	46	9
25	46	9
26	46	9
27	46	10
28	46	10
29	46	11
30	45	11

	Dry (%)	Comfortable (%)
1	94	6
2	95	5
3	96	4
4	96	4
5	97	3
6	97	3
7	98	2
8	98	2
9	99	1
10	99	1
11	99	1
12	99	1
13	99	1
14	100	0
15	100	0
16	100	0
17	100	0
18	100	0
19	100	0
20	100	0
21	100	0
22	100	0
23	100	0
24	100	0
25	100	0
26	100	0
27	100	0
28	100	0
29	100	0
30	100	0

	Avg high (°C)	Avg low (°C)
1	17	8
2	17	8
3	17	8
4	16	8
5	16	8
6	16	8
7	16	8
8	16	7
9	16	7
10	16	7
11	15	7
12	15	7
13	15	7
14	15	7
15	15	7
16	15	6
17	15	6
18	14	6
19	14	6
20	14	6
21	14	6
22	14	6
23	14	6
24	14	6
25	14	5
26	14	5
27	13	5
28	13	5
29	13	5
30	13	5

	Clearer (%)	Cloudier (%)
1	50	50
2	50	50
3	50	50
4	50	50
5	49	51
6	49	51
7	50	50
8	50	50
9	49	51
10	48	52
11	48	52
12	47	53
13	47	53
14	47	53
15	45	55
16	45	55
17	45	55
18	43	57
19	43	57
20	43	57
21	42	58
22	42	58
23	42	58
24	42	58
25	43	57
26	42	58
27	42	58
28	41	59
29	41	59
30	40	60

	Rain chance (%)	Snow chance (%)
1	52	5
2	52	5
3	52	5
4	52	5
5	51	5
6	51	6
7	51	6
8	51	6
9	51	6
10	51	7
11	50	7
12	50	7
13	50	7
14	50	8
15	49	8
16	49	8
17	49	8
18	49	9
19	48	9
20	48	9
21	47	9
22	47	9
23	46	9
24	46	9
25	46	9
26	46	9
27	46	10
28	46	10
29	46	11
30	45	11

	Dry (%)	Comfortable (%)
1	94	6
2	95	5
3	96	4
4	96	4
5	97	3
6	97	3
7	98	2
8	98	2
9	99	1
10	99	1
11	99	1
12	99	1
13	99	1
14	100	0
15	100	0
16	100	0
17	100	0
18	100	0
19	100	0
20	100	0
21	100	0
22	100	0
23	100	0
24	100	0
25	100	0
26	100	0
27	100	0
28	100	0
29	100	0
30	100	0