Ascona Weather in September
With daytime temperatures of 19°C (66°F) and nighttime lows of 10°C (50°F), September in Ascona brings pleasant temperatures during the day. Do keep in mind that September is part of the rainy season, with frequent and often heavy rainfall.
Rainfall in Ascona in September
Ascona is in the rainy season in September, with rain on around 13 days and an average of 194 mm (7.6 in). Rainy season showers tend to be fairly substantial. A good rain jacket or umbrella is worth having with you most days.
Temperature in Ascona in September
September in Ascona brings typical temperatures with highs around 19°C (66°F) and lows of 10°C (50°F). Temperatures can feel cooler in the morning and evening, so layering is often the best approach. With lows around 10°C (50°F), nights are cold. The upside is that cool, crisp nights are often the best for a deep sleep.
Sunshine in Ascona in September
Expect a lot of sunshine this month, with about 199 hours of sun. Showers typically arrive in the late afternoon or evening, keeping mornings and early afternoons sunny. Even during the wet season, there's plenty of sunshine for sightseeing.
Wind Speed in Ascona in September
September has wind speeds averaging 1 m/s (2 knots). You can expect very gentle conditions with light air movement on typical days. Since this is an average, daily weather varies from perfectly still moments to some breezier days.Our weather planner can help you find worldwide destinations with pleasant weather during this period. June, July and August typically offer the best weather for Ascona.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Switzerland, check out our Ascona's climate page.
Ascona Temperature in September
Min Temperature
10°C (50°F)
Max Temperature
19°C (66°F)
Chance of Rain
43%
Precipitation
194 mm (7.6 in)
Rainy days
13 days
Humidity
72% *
Windspeed
1 m/s (2 knots) *
Sunshine
199 hours *
Percentage Sunshine
56% *
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Ascona typically drop from around 24°C (75°F) at the start of September to approximately 20°C (68°F) by the end. Nights are cool, with lows typically ranging from 11°C (52°F) to 14°C (57°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Ascona in September
Browse day-by-day weather records for Ascona spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Ascona historical weather extremes in September
Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Ascona.
- Ascona recorded its highest September temperature of 34°C (93°F) on September 25, 1983.
- Ascona experienced its chilliest September day on September 27, 2007, reaching only 9°C (48°F).
- Ascona registered its coldest September night on September 18, 1977, with temperatures dropping to -4°C (25°F).
Best Places in Switzerland in September
Find out more about the weather in Switzerland and which places have the best travel conditions in this month. See all of Switzerland in September →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Ascona in September
Comfortable temperatures call for an easy wardrobe in September. Pack summer basics like t-shirts and shorts, but include a light jacket for cooler moments. A pair of comfortable walking shoes is essential. It's going to pour! Pack a good poncho and prepare for very wet conditions. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.What To Do in Ascona in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Switzerland, check out our Ascona's climate page.
Temperature Rainfall Sunshine Humidity Wind Speed
See the full Ascona climate overview or explore weather in Switzerland.
