Sion Weather in September

Sion in September averages 15°C (59°F) during the day and 3°C (37°F) at night. Keep in mind that quite a bit of rainfall is expected this month.

Rainfall in Sion in September

Climate statistics over the past 30 years suggest around 14 days of rain, with 127 mm (5 in) average for the month. The rain this month tends to fall in heavier spells rather than light drizzle. When it rains, showers can be significant.

Temperature in Sion in September

In September, Sion sees moderate temperatures, with highs of 15°C (59°F). Nights drop to around 3°C (37°F). Conditions are often most pleasant around the middle of the day. Nights drop to 3°C (37°F). Cold nights like these are actually great for sleeping well, as long as you have a warm enough duvet.

Sunshine in Sion in September

Expect a lot of sunshine this month, with about 210 hours of sun. These sunny conditions help offset the cool temperatures, making it a pleasant month to explore outdoors.

Wind Speed in Sion in September

Average wind conditions reach 2 m/s (4 knots) in September. This creates comfortable weather with light winds that gently move vegetation. Keep in mind this is an average. Daily conditions range from near-calm to more noticeable wind.

If you prefer dry days with pleasant temperatures, July and August typically offer the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.

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• January
• February
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• May
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• October
• November
• December

For a detailed overview over the year and the best time to visit Switzerland, check out our Sion's climate page.

Sion Temperature in September

Min Temperature 3°C (37°F)  

Max Temperature 15°C (59°F)  

Chance of Rain 47%  

Precipitation 127 mm (5 in)  

Rainy days 14 days  

Humidity 71%  

Windspeed 2 m/s (4 knots)  

Sunshine 210 hours  

Percentage Sunshine 65%  

What to Wear in Sion in September

Pack for changing conditions in Sion in September. Bring a mix of short and long sleeves, a warm layer like a hoodie or light jacket, and comfortable pants. The key is being able to add or remove layers as the days goes by. Prepare for significant rainfall with proper waterproof clothing and shoes. And with plenty of sunshine hours, don’t forget sunglasses, sunscreen, and maybe a sun hat.

What To Do in Sion in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

4/10

Cycling

5/10

Walking

5/10

Camping

3/10

Outdoor sports

9/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Switzerland, check out our Sion's climate page.

More climate data for Sion

Temperature Rainfall Sunshine Humidity Wind Speed

See the full Sion climate overview or explore weather in Switzerland.