Arosa weather in September
Temperature, rain and sunshine in September: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in September
Fair
Best time to visit: July – August
Best for skiing: November – April
What is the weather like in Arosa in September?
In September, Arosa is cool: daytime highs average 13 °C, and nights cool down to about 4 °C. Expect around 5 hours of sunshine a day. Rain is frequent, with about 13 rainy days and 118 mm in total. Snow falls on about 3 days. All in all, September is a so-so month for a holiday in Arosa.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 64 | 52 | 31 |
| Day | 17° | 13° | 9° |
| Night | 8° | 4° | 0° |
| Sun | 6 h | 5 h | 4 h |
| Rain days | 16 | 13 | 12 |
More details for September
- Daylight
- 12 h 38 min06:58 – 19:36
- UV index
- 5 · moderateclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or moreAll months
- Wind
- 7 km/haverage daily peakAll months
- Cloud cover
- 70 %on averageAll months
- Hot days
- 0 days30 °C or more
- Snow days
- 3 days1 cm or more of fresh snowAll months
- Time zone
- UTC+2Europe/Zurich
How the score comes together
- Temperatureweight 50 %71 %
- Sunshineweight 20 %35 %
- Few rainy daysweight 30 %33 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Mountain air”.
What to pack in September
- Sunscreen
- A jumper for the evenings
- Hat, scarf & gloves
- Rain jacket or umbrella
Arosa in September: quick answers
Is Arosa hot in September?
No. In September, Arosa is cool: daytime highs average 13 °C and nights drop to about 4 °C.
Does it rain much in Arosa in September?
Rain is frequent, with about 13 rainy days and 118 mm in total.
Arosa month by month
The whole year in ArosaAll destinations: SwitzerlandWhere to go in September
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences