Early September 1 September
73°F
Typical afternoon high
33% historical wet-day frequency
Switzerland · Mountains
Is September a good time?
September averages 69°F afternoons, with about 10 rain days. Later September is typically cooler.
Historical Espace Mittelland regional averages, not a forecast or a measure of queues. Overnight demand compares average stays per day. Covers Interlaken, Grindelwald, Jungfrau, Bern and Lauterbrunnen; conditions vary within the region.
This weather score measures sightseeing comfort. Snow and ski conditions need a separate check.
What matters most?
Weather 50% · Crowds 30% · Cost 20%
#1 of 12 months here · Balanced mix
Overall combines weather, overnight demand and cost. It does not include sea temperature.
Plan your September
Afternoons around 69°F (21°C): light layers; nights around 49°F (10°C): a sweater and a light jacket. Bring rain gear: about 10 days with at least 1 mm of rain. About 13 hours of daylight.
The sun rises about 07:06 and sets about 19:45 (local time, mid-month). Mornings start around 49°F (10°C); afternoons reach about 69°F (21°C). Expect rain on about 10 days in a typical September.
Early, middle or late?
Early September is typically warmer. The afternoon high averages 73°F on the 1st, versus 65°F on the 30th. Historical wet-day frequency rises from 33% to 39% between those dates.
73°F
Typical afternoon high
33% historical wet-day frequency
69°F
Typical afternoon high
36% historical wet-day frequency
65°F
Typical afternoon high
39% historical wet-day frequency
Historical daily averages from 2011–2025, smoothed over two weeks. A seasonal pattern, not a forecast. This does not establish which week has the lowest prices or fewest visitors.
Weather shows historical patterns, not a forecast. Holidays and events use the dates shown for 2027.
| Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|
| 173° | 273° | 373° | 472° | 572° | ||
| 672° | 771° | 871° | 971° | 1071° | 1171° | 1270° |
| 1370° | 1470° | 1569° | 1669° | 1768° | 1868° | 1968° |
| 2067° | 2167° | 2267° | 2367° | 2466° | 2566° | 2666° |
| 2766° | 2865° | 2965° | 3065° |
Afternoon high rain likely (25%+) local school holidays public holiday event
School-holiday dates for September 2027 aren't available in our data yet. A day without a school marker doesn't mean schools are open.
Afternoons cool from about 72°F (22°C) in the first week to 66°F (19°C) in the last. The chance of a wet day runs 32–39%.
Visitor season
Busy season. September averages 70% of July's overnight stays per day. Fewer overnight stays than August.
Overnight stays across Espace Mittelland do not measure queues, day visitors or congestion at individual sights. For its size, typical for Europe this month.
Hotel price season
About usual. Estimated from national hotel prices and local visitor demand; no measured regional room rate is available.
Fewer overnight stays do not automatically mean cheaper rooms. Check actual quotes for your trip.
Year-to-year variation
In the 15 years from 2011 to 2025, the month's afternoons averaged between 64°F (18°C) and 76°F (24°C); in 9 of them they were within 3°F (1.5°C) of the typical 69°F (21°C). Rain days ranged from 6 to 16; half the years had 8–14.
Rain days in each September
| Year | Afternoon high | Rain days |
|---|---|---|
| 2011 | 72°F | 9 |
| 2012 | 67°F | 11 |
| 2013 | 68°F | 14 |
| 2014 | 69°F | 10 |
| 2015 | 64°F | 11 |
| 2016 | 71°F | 8 |
| 2017 | 64°F | 11 |
| 2018 | 73°F | 7 |
| 2019 | 69°F | 9 |
| 2020 | 70°F | 8 |
| 2021 | 71°F | 7 |
| 2022 | 67°F | 15 |
| 2023 | 76°F | 6 |
| 2024 | 66°F | 15 |
| 2025 | 67°F | 16 |
Checked against 25 local weather stations. How we check
Compare dates
| Typical conditions | Aug | Sep | Oct |
|---|---|---|---|
| Afternoons | 77°F | 69°F | 61°F |
| Rain days | 11 | 10 | 10 |
| Overnight demand | 99% | 70% | 52% |
August: Warmer afternoons than September. More overnight demand. August guide →
October: Cooler afternoons than September. Less overnight demand. October guide →
Overnight demand measures accommodation stays, not queues.
Yellow marks the top three months on the Balanced mix. September stays as your reference.
No other scored month has a Weather score at least 1.0 point higher than September.
Your comparison
Overnight stays are 99% of the busiest month.
National hotel prices and local visitor demand suggest a little above usual. No measured regional room rate is available.
Read the August guide →| Typical conditions | September | August |
|---|---|---|
| Afternoons | 69°F | 77°F |
| Nights | 49°F | 56°F |
| Rain days | 10 | 11 |
| Visitor season | Busy season | Peak season |
| Overall / 10 | 6.3 | 5.5 |
| Month rank | #1 | #9 |
| Month | Overall | Rank | High | Low | Rain days | Weather | Visitor season |
|---|---|---|---|---|---|---|---|
| January | 4.8 | #12 | 42°F | 28°F | 15 | 3.9 | Moderate season |
| February | 5.0 | #11 | 46°F | 28°F | 9 | 4.7 | Moderate season |
| March | 5.9 | #6 | 53°F | 33°F | 11 | 5.8 | Moderate season |
| April | 6.1 | #2 | 60°F | 39°F | 10 | 6.6 | Moderate season |
| May | 5.9 | #5 | 65°F | 46°F | 14 | 7.0 | Busy season |
| June | 6.0 | #3 | 74°F | 54°F | 11 | 8.1 | Busy season |
| July | 5.6 | #8 | 77°F | 56°F | 12 | 8.3 | Peak season |
| August | 5.5 | #9 | 77°F | 56°F | 11 | 8.2 | Peak season |
| September | 6.3 | #1 | 69°F | 49°F | 10 | 8.2 | Busy season |
| October | 6.0 | #4 | 61°F | 42°F | 10 | 6.7 | Moderate season |
| November | 5.8 | #7 | 50°F | 35°F | 11 | 4.8 | Low season |
| December | 5.2 | #10 | 44°F | 30°F | 15 | 4.0 | Moderate season |
Near here
Nearby regions, nearest first. Distances are centre to centre, as the crow flies; they are not road distances or journey times.
Lake Geneva & ValaisSwitzerland · about 40 miles
Balanced Overall 6.4 · Very good weather, 71°F (22°C) · Busy season · Cost expensive
Basel & northwest Switzerlandabout 50 miles
Balanced Overall 6.5 · Very good weather, 71°F (22°C) · Steady all year · Cost expensive
Lyon & the French AlpsRhône-Alpes · France · about 140 miles
Balanced Overall 8.2 · Very good weather, 74°F (23°C) · Moderate season · Cost pricey
Milan, Lake Como & LombardyItaly · about 140 miles
Balanced Overall 7.2 · Excellent weather, 76°F (25°C) · Busy season · Cost pricey
TrentinoItaly · about 180 miles
Balanced Overall 7.8 · Excellent weather, 73°F (23°C) · Moderate season · Cost pricey
Elsewhere in Europe
Bern & the Bernese Oberland's weather ranks 18 of 28 mountain regions this month. These mountain regions outside Switzerland have clearly better weather on your dates, nearest first, each compared with Bern & the Bernese Oberland.
La RiojaSpain · about 580 miles
Excellent weather (9.2): 10°F warmer afternoons, 6 fewer rain days, cheaper
Brașov, Sibiu & central TransylvaniaRomania · about 830 miles
Excellent weather (9.2): 3°F warmer afternoons, 4 fewer rain days, cheaper
Western MacedoniaGreece · about 830 miles
Excellent weather (9.6): 10°F warmer afternoons, 6 fewer rain days, quieter for its season (moderate season), cheaper
Sofia & the southwestBulgaria · about 840 miles
Excellent weather (9.8): 7°F warmer afternoons, 6 fewer rain days, cheaper
It's busy season, 70% of the busiest month and 20% above its average month. That means about 38,000 overnight visitors on a typical September night across the region, 48% of them from Switzerland itself. Rentals booked through Airbnb, Booking, Expedia and Tripadvisor add up to 8,600 more: 23 for every 100 counted above. Some are the same properties counted twice.
| Climate suitability (HCI:Urban, 0–100) | 76 |
| How our weather was checked | 25 open weather stations in this region, January and July: afternoon highs typically within 1°F (0.8°C), night lows within 1°F (0.2°C). |
| Tourist nights per 1,000 residents per day | 19 |
| Busiest month here | July · 27 |
| Visitors as share of people present | 1.9% |
| Rank among Europe's regions this month | 62nd percentile |
| Domestic share of nights | 48% |
| Platform rental nights per 100 counted nights | 23 |
| Visitor share if every platform night were extra | 2.3% |
| National hotel-price season | Switzerland historical 2024–2025 index: About usual (+2% vs its average month). Not a local room quote. |
| Population used | 2.0 million |
| Statistical region | CH02 · Espace Mittelland |
Crowds: Eurostat nights spent at tourist accommodation, by month and NUTS 2 region, 2024–2025 average. Overnight visitors per night is the month's nights divided by its days; the per-1,000 figure is Eurostat's, against each year's population. Platform rentals: Eurostat nights booked via Airbnb, Booking, Expedia and Tripadvisor, 2024–2025 average, shown separately because some properties are in both counts. Weather: Holiday Climate Index computed from ERA5 reanalysis with daily highs, night lows and rain days corrected from open national weather-service station records, 2011–2025, population-weighted to the region; day-by-day figures are the same data averaged by date. Heat and rain odds are counted across those years. Sunrise and sunset: NOAA solar equations, local time. Prices: Eurostat price level index and HICP, national. Full method · this region's data.