🇫🇷 Weather in Chamonix in September
This is what the weather in Chamonix (Haute-Savoie, France) was like in September in 2017–2026.
Key facts at a glance
Avg. daytime high
15.9 °C
11.9 °C – 20.3 °C
Avg. night-time low
5.5 °C
2.6 °C – 7.7 °C
Avg. rain days in period
12.9
43 % of days · ≥ 1.0 mm
Avg. precipitation in period
89.2 mm
15.4 mm – 214 mm
Avg. sunshine per day
n/a
Sunshine duration is not available from this data source.
Avg. sea temperature
–
No sea nearby – no sea temperature.
Extremes: Highest temperature 26.6 °C (4 Sep 2026) · Lowest temperature -4.5 °C (27 Sep 2020) · Avg. daily peak wind 9 km/h
Weather mix of all days
- 51Sunny
- 74Partly cloudy
- 18Cloudy
- 77Light rain
- 52Rain
Summary
- On average 15.9 °C during the day and 5.5 °C at night.
- On average 12.9 rain days (Rain day = at least 1.0 mm of precipitation) with 89.2 mm of precipitation in total.
- Prevailing: Light rain.
- Warmest year: 2026 (avg. 20.3 °C), coolest: 2017 (avg. 11.9 °C).
- Wettest year: 2024 (214 mm), driest: 2026 (15.4 mm).
- Extremes: 26.6 °C on 4 Sep 2026 and -4.5 °C on 27 Sep 2020.
Overall values from all 10 years. How is this calculated?
Charts
Temperatures per year
Average over your travel period
Precipitation & rain days
Year by year
2026
Avg. max20.3°Avg. min7.6°- Rain days
- 2 Rain days
- Precipitation
- 15.4 mm
- Avg. sunshine per day
- n/a
- Sea temperature
- –
Max 26.6 °C · Min 3.2 °C
2025
Avg. max14.7°Avg. min4.7°- Rain days
- 18 Rain days
- Precipitation
- 133 mm
- Avg. cloud cover
- 65 % cloudy
- Sea temperature
- –
Max 24.5 °C · Min 0.0 °C
2024
Avg. max13.1°Avg. min3.8°- Rain days
- 18 Rain days
- Precipitation
- 214 mm
- Avg. cloud cover
- 77 % cloudy
- Sea temperature
- –
Max 20.8 °C · Min -3.3 °C
2023
Avg. max19.4°Avg. min7.7°- Rain days
- 10 Rain days
- Precipitation
- 66.4 mm
- Avg. cloud cover
- 51 % cloudy
- Sea temperature
- –
Max 25.5 °C · Min -1.1 °C
2022
Avg. max14.5°Avg. min4.6°- Rain days
- 21 Rain days
- Precipitation
- 136 mm
- Avg. cloud cover
- 64 % cloudy
- Sea temperature
- –
Max 24.8 °C · Min -2.1 °C
2021
Avg. max15.9°Avg. min6.4°- Rain days
- 12 Rain days
- Precipitation
- 70.4 mm
- Avg. cloud cover
- 59 % cloudy
- Sea temperature
- –
Max 19.2 °C · Min -0.6 °C
2020
Avg. max15.6°Avg. min5.7°- Rain days
- 15 Rain days
- Precipitation
- 103 mm
- Avg. cloud cover
- 54 % cloudy
- Sea temperature
- –
Max 22.9 °C · Min -4.5 °C
2019
Avg. max15.8°Avg. min5.5°- Rain days
- 10 Rain days
- Precipitation
- 51.0 mm
- Avg. cloud cover
- 54 % cloudy
- Sea temperature
- –
Max 22.2 °C · Min 1.0 °C
2018
Avg. max17.6°Avg. min6.3°- Rain days
- 10 Rain days
- Precipitation
- 47.5 mm
- Avg. cloud cover
- 46 % cloudy
- Sea temperature
- –
Max 22.4 °C · Min -0.4 °C
2017
Avg. max11.9°Avg. min2.6°- Rain days
- 13 Rain days
- Precipitation
- 55.0 mm
- Avg. cloud cover
- 64 % cloudy
- Sea temperature
- –
Max 18.4 °C · Min -1.7 °C
Frequently asked questions
- How warm is it in Chamonix in September?
- Daytime highs averaged 15.9 °C, night-time lows 5.5 °C. The highest value of the past 10 years was 26.6 °C (4 Sep 2026), the lowest -4.5 °C (27 Sep 2020).
- How often does it rain in Chamonix in September?
- On average there were 12.9 rain days (at least 1 mm) with 89.2 mm of precipitation in total.
Check your exact travel dates
Choose your travel period – we show the weather for exactly those days.
Other destinations in September
Data sources
- Weather data
- Data obtained from the NASA Langley Research Center (LaRC) POWER Project funded through the NASA Earth Science/Applied Science Program
Reanalysis (weather model constrained by observations) on a coarse grid of about 50 km. Values represent a large area and can differ from local conditions, especially on islands, coasts and in mountains. Snow depth is the model value for the grid cell, not the depth on the slopes. No sunshine duration.
Reanalysis (weather model constrained by observations)
Reanalysis values represent a grid cell (approx. 25–50 km) and may differ from local measurements on coasts, islands and in mountains. - Sea temperature
- MUR SST data were provided by JPL under support by NASA MEaSUREs program; accessed via NOAA CoastWatch ERDDAP
Daily multi-scale ultra-high resolution (≈ 1 km) analysis of satellite measurements (infrared, microwave) and in-situ data. Represents the foundation temperature below the daily warm surface layer. (Satellite and in-situ analysis) - Place search
- Natural Earth (public domain) · GeoNames (CC BY 4.0) / OpenStreetMap (ODbL)