September · France
Best time to visit Mont Blanc in September Weather, crowds & prices
Weather in Mont Blanc in September
Average temperature 10°C, 139 mm of rain, about 13 days with 6+ hours of sunshine and 75% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
September score
6.7/10
Ranked #5 of 12 months
- Avg temp
- 10°C
- Rainfall
- 139 mm
- Humidity
- 75%
- Days with 6h+ sun
- 13
- Crowd Density
- Moderate Crowds
- Average Expenses
- $$ · Moderate Cost ($$)
September in Mont Blanc scores 6.7/10 for nature and wildlife travel - an above-average month (#5 of 12). Expect around 10°C, 139 mm of rain, and roughly 13 days with 6+ hours of sunshine this month.
Mont Blanc's massif rises above Chamonix and Courmayeur, with glaciers, cable cars and alpine trails.
September in Mont Blanc — workable with trade-offs
Expect 10°C (50°F) in September. A good month for city streets, viewpoints and long meals; leave swimming for another season.
139 mm of rain signals a properly wet month, with only about 13 days with 6+ hours of sunshine to count on — build indoor options into the schedule.
That is 6.7/10 on the same scale — 5th of 12 months, versus 9.2/10 for the best month here.
Pack a mid-weight jacket, long sleeves and shoes you can walk 15 km in, a proper rain shell rather than an umbrella, footwear you can get muddy.
Budget for mid-season pricing, and crowds are moderate.
If your dates are flexible, July is materially better in Mont Blanc — 2.5 points higher on the same scale.
Frequently asked
- What is the weather like in Mont Blanc in September?
- In September, Mont Blanc averages 10°C, 139 mm of rain, and about 13 days with 6+ hours of sunshine. Its climate-comfort score is 6.7/10.
- Is September a good time to visit Mont Blanc?
- September earns a 6.7/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Mont Blanc in September?
- Expect about 139 mm of rain in September. Average humidity is 75% and there are about 13 days with 6+ hours of sunshine.
Curated in Mont Blanc
Tickets & experiences
Things to do in Mont Blanc
Mont Blanc, France. Live activities and tours from GetYourGuide, matched to this destination.