What to expect in Swiss Alps (Interlaken) in September
September is one of the best times to visit Swiss Alps (Interlaken). Expect 19° / 10°, manageable crowds at the big attractions and prices close to the yearly average.
Swiss Alps (Interlaken) weather in September
Typical conditions in Swiss Alps (Interlaken) during September, based on long-run climate normals rather than any single year. Treat it as a planning guide, not a forecast.
| Average high | 19°C 66°F |
|---|---|
| Average low | 10°C 50°F |
| Rainfall | Moderate 40/100 |
| How it feels | Mild — layers weather |
Average highs sit around 19°C with lows near 10°C. Rainfall is moderate; the odd shower is likely.
Crowds & demand
Crowd levels are Moderate for Swiss Alps (Interlaken) — manageable crowds at the big attractions.
Prices & value
Prices run mid-range this month: prices close to the yearly average.
What to pack
Layers you can shed: 19°C by day and about 10°C after dark is a two-jacket kind of month.
What it costs
Costs in September sit around the yearly average for Swiss Alps (Interlaken) — neither a bargain nor a squeeze. Booking a few weeks out is usually enough. Compared with the most expensive month of the year, you are looking at roughly 35% less.
Who this month suits
- Travellers who want the most reliable weather
- Anyone travelling on a budget
- Visitors who want to catch a festival
Events & what’s on
Look out for Jungfrau Marathon, Alpabzug (Alpine Cattle Descent) while you’re there.
- Jungfrau Marathon — Runners climb over 1,800 meters from Interlaken to Kleine Scheidegg beneath three of the Alps' most famous peaks.
- Alpabzug (Alpine Cattle Descent) — Flower-crowned cows parade down from high summer pastures into valley villages to mark the end of the grazing season.
Swiss Alps (Interlaken) in September compared with nearby months
If your dates are flexible by a few weeks, this is what shifting them actually buys you.
| Month | Temp | Crowds | Price | Score |
|---|---|---|---|---|
| July | 24° / 13° | High | $$$ | 49 |
| August | 23° / 13° | High | $$$ | 46 |
| September · This month | 19° / 10° | Moderate | $$ | 58 |
| October | 13° / 5° | Low | $ | 61 |
| November | 7° / 1° | Low | $ | 62 |
These months score higher for Swiss Alps (Interlaken) on the same blend of weather, crowds and price. Same destination, better odds.
Or go somewhere else in September
If the destination is negotiable but the month is not, these places are at their best in September.
Figures are climate normals and modelled estimates — a planning guide, not a forecast. We separate fact, estimate and recommendation. Updated August 2026
