Sion weather in August
Temperature, rain and sunshine in August: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in August
Good
Best time to visit: May – October
What is the weather like in Sion in August?
In August, Sion is warm: daytime highs average 25 °C, and nights cool down to about 14 °C. The sun shines for around 8 hours a day. It rains often – on about 16 days, adding up to 163 mm. All in all, August is a good month for a holiday in Sion.
August compared
How the weather changes from July to September. Tap a month to open it.
| JulyJul | AugustAug | SeptemberSep | |
|---|---|---|---|
| Score | 71 | 72 | 73 |
| Day | 25° | 25° | 21° |
| Night | 14° | 14° | 11° |
| Sun | 9 h | 8 h | 7 h |
| Rain days | 17 | 16 | 13 |
More details for August
- Daylight
- 14 h 14 min06:29 – 20:42
- UV index
- 7 · highclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or moreAll months
- Wind
- 8 km/haverage daily peakAll months
- Cloud cover
- 58 %on averageAll months
- Hot days
- 3 days30 °C or moreAll months
- Snow days
- 0 days1 cm or more of fresh snowAll months
- Time zone
- UTC+2Europe/Zurich
How the score comes together
- Temperatureweight 50 %100 %
- Sunshineweight 20 %85 %
- Few rainy daysweight 30 %15 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Mountain air”.
What to pack in August
- Sunscreen
- Sunglasses & sun hat
- A jumper for the evenings
- Rain jacket or umbrella
Sion in August: quick answers
Is Sion hot in August?
Warm rather than hot: in August, daytime highs in Sion average 25 °C and nights cool to about 14 °C. On about 3 days the thermometer climbs to 30 °C or more.
Does it rain much in Sion in August?
It rains often – on about 16 days, adding up to 163 mm.
Sion month by month
The whole year in SionAll destinations: SwitzerlandWhere to go in August
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