Last updated: August 27, 2025
September in Ascona, Switzerland offers a captivating blend of mild temperatures and refreshing weather. The maximum temperature reaches a pleasant 23°C (74°F), while the average settles at a cool 13°C (55°F), making it ideal for outdoor exploration. However, be prepared for the occasional chill, as minimum temperatures can dip to -1°C (31°F). This month typically sees 136 mm (5.4 in) of precipitation over approximately 14 days, so visitors should expect a fair share of rain. With a high humidity level of 83%, the air is crisp yet invigorating, perfectly complementing the stunning natural beauty of the region.
September in Ascona, Switzerland, marks a delightful transition into autumn, with temperatures reflecting a pleasant shift from the warmth of summer. The month typically begins with a minimum temperature of -1°C (31°F), rising to a comfortable average of 13°C (55°F) and peaking at a maximum of 23°C (74°F). This range creates an inviting atmosphere for outdoor enthusiasts, as the crisp air enhances the beauty of the surrounding landscapes. The gradual decline in temperature compared to the balmy August invites locals and visitors alike to embrace the changing leaves and partake in cozy activities, making September a truly enchanting time to experience Ascona's charm.
In September, Ascona experiences a balanced transition into autumn with precipitation totaling 136 mm (5.4 in), falling over approximately 14 days. This marks a noteworthy consistency in rainfall compared to the late summer months, as it mirrors August's totals while maintaining the trend of increased moisture that begins in spring. The month acts as a precursor to the more dramatic increases seen in October, which typically continues the pattern of heavier rainfall—highlighting the distinctive wet spell of northern Switzerland as summer fades. As the landscape transforms with the onset of fall, September’s rain nourishes the vibrant foliage, setting a picturesque stage for the changing season.
In September, Ascona experiences a notable shift in humidity, averaging around 83%. This marks a slight increase from the preceding summer months, where humidity dipped to a comfortable 80% in both May and August. As the season transitions towards autumn, the humidity levels in September begin to rise, echoing the trend observed in earlier months like June and July. However, this figure remains significantly lower than the winter spikes, exemplified by a high of 92% in January. Overall, September’s humidity reflects a blend of summer warmth lingering in the air, while subtly hinting at the moist, crisp conditions to come with autumn.
As September arrives in Ascona, Switzerland, residents and visitors alike can expect a high UV Index of 7, signifying a shift from the intense summer months. With a burn time of approximately 25 minutes, this month's solar exposure remains notable, although less fierce than the scorching peaks of July and June, both reaching a UV Index of 10. As autumn approaches, the UV Index gradually decreases, transitioning to a moderate level in October. This pattern highlights a trend of diminishing UV strength as the year progresses, making September an ideal time for outdoor activities while still taking necessary sun protection measures. For more detailed insights, visit Ascona UV Index.
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As summer gracefully transitions into autumn, September in Ascona, Switzerland, continues to bask in the warmth of sunshine, offering 302 hours of delightful light. This month marks a gentle decline from the sun-drenched peak of July, which boasts an impressive 404 hours. Interestingly, September keeps the spirit of summer alive, outshining both October and the cooler months ahead. With a gradual decrease in hours from the vibrant 350 hours in May to September's glow, it captures the essence of early autumn, where the lingering warmth invites both locals and visitors to savor the stunning lakeside views and charming streets before winter sets in. As the days grow shorter, September still serves as a vibrant reminder of summer's enduring beauty.
In Ascona, Switzerland, September offers a decent chance of sunny weather, with a 35% likelihood of sunshine. This month's sunshine probability sits comfortably between the summer's peak in August at 50% and the lower percentages seen in the early months of the year, like January's 31%. While September sees a slight dip from late summer, it maintains a favorable position in the annual trend of sunshine, ensuring visitors can still enjoy pleasant days. As a transition month into autumn, it presents a perfect opportunity to soak up the last rays of summer before the cooler weather sets in.
As the summer sun sets gently in September, Ascona experiences a transition, with daylight lasting approximately 12 hours. This month marks a noticeable decline from the peak of 15 hours in June and July, highlighting the gradual shift towards autumn. The days are still pleasantly long enough to enjoy outdoor activities, yet shorter than the vibrant light of May and early summer. As the seasons progress towards October, daylight continues to wane, reminding us of nature's rhythm as it prepares for the colder months ahead. The fading daylight not only captures the essence of changing seasons but also invites reflection on the beauty of time passing in this charming Swiss town.
As September arrives in Ascona, Switzerland, the gentle caress of the wind reaches an average speed of just 1.2 m/s (3 mph), marking a subtle quietude compared to the slightly more invigorating breezes of earlier summer months. This seasonal shift is part of an intriguing trend: while the wind remains relatively calm throughout the summer, it begins to pick up speed again in the following months, culminating in a brisk 2.0 m/s (5 mph) by December. The transition to autumn brings a serene atmosphere ideal for leisurely strolls along the lakeside, where nature's stillness is occasionally roused by the soft whispers of the wind, creating a picturesque backdrop for relaxation and reflection.
Weather in Ascona varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Ascona, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparison to September, January experiences significantly colder temperatures, with minimums dropping to -16°C (4°F) compared to September's mild lows of -1°C (31°F). While September boasts an average temperature of 13°C (55°F) and a maximum of 23°C (74°F), January's averages hover around -2°C (29°F) and peak at just 9°C (49°F). Additionally, precipitation is more frequent in September, occurring on 14 days and totaling 136 mm (5.4 in), whereas January sees less rain, with 10 days of precipitation amounting to 71 mm (2.8 in). Despite the lower rainfall, January's humidity levels are higher at 92%, compared to September's 83%. For more details, you can refer to Ascona weather in January.
September and February present contrasting weather conditions. In September, temperatures range from a chilly minimum of -1°C (31°F) to a pleasant maximum of 23°C (74°F), with an average of 13°C (55°F). The month experiences significant rainfall, accumulating 136 mm (5.4 in) over 14 days at a humidity level of 83%. In stark contrast, February is much colder, with temperatures dipping as low as -17°C (2°F), averaging just 1°C (34°F), and reaching a maximum of 17°C (63°F). Precipitation is lighter in February, totaling 56 mm (2.2 in) over 11 days, while humidity rises slightly to 89%. For more detailed insights, you can check Ascona weather in February.
September and March showcase contrasting weather patterns, with September exhibiting milder temperatures ranging from a minimum of -1°C (31°F) to a comfortable maximum of 23°C (74°F) and an average of 13°C (55°F). In contrast, March is considerably colder, with temperatures fluctuating between -17°C (3°F) and a maximum of 18°C (64°F), yielding an average of just 3°C (37°F). Both months experience a fair amount of precipitation, with September receiving 136 mm (5.4 in) over 14 days, while March sees slightly less rain at 106 mm (4.2 in) across 12 days. Additionally, humidity levels are relatively high in both months, with September at 83% and March reaching 87%. For a detailed look at March weather in Ascona, you can visit Ascona weather in March.
In comparing the weather of September and April, we see distinct differences in temperature and humidity levels. September boasts a milder temperature range with a minimum of -1°C (31°F), an average of 13°C (55°F), and a maximum of 23°C (74°F), while April's cooler conditions feature a minimum of -6°C (21°F), an average of 7°C (44°F), and a maximum of 20°C (68°F). Both months experience similar precipitation levels, with September seeing 136 mm (5.4 in) over 14 days and April recording 136 mm (5.3 in) over 10 days. Interestingly, September’s humidity is slightly lower at 83%, compared to April's 84%, indicating a slightly more discomforting feel in the early spring. For more insights on April weather, you can refer to Ascona weather in April.
September and May showcase distinct weather patterns, reflecting the transitions of their respective seasons. In September, temperatures range from a minimum of -1°C (31°F) to a maximum of 23°C (74°F), with an average of 13°C (55°F). The month experiences 136 mm (5.4 in) of precipitation over about 14 days, accompanied by a relatively high humidity level of 83%. In contrast, May presents slightly cooler temperatures, with a minimum of -7°C (21°F) and a maximum of 25°C (77°F), averaging 11°C (51°F). Rainfall in May is higher, totaling 176 mm (6.9 in) across roughly 19 days, while humidity hovers around 80%. For more detailed insights about the weather during this month, visit Ascona weather in May.
In September, temperatures range from a chilly minimum of -1°C (31°F) to a mild maximum of 23°C (74°F), with an average of 13°C (55°F). The month sees substantial rainfall, with 136 mm (5.4 in) over approximately 14 days and a humidity level of 83%. In contrast, June experiences warmer temperatures, with a minimum of 5°C (41°F) and a maximum of 34°C (93°F), averaging around 15°C (60°F). Despite June receiving slightly higher precipitation at 159 mm (6.3 in) over 18 days, humidity is marginally lower at 82%. For a closer look at June weather patterns, check out Ascona weather in June.
In comparing the weather between September and July, we see notable differences in temperature and precipitation. September experiences cooler temperatures, with a minimum of -1°C (31°F) and an average of 13°C (55°F), compared to July's milder minimum of 6°C (44°F) and average of 17°C (63°F). The maximum temperature in September reaches 23°C (74°F), while July typically peaks at a warmer 27°C (80°F). Precipitation in September is slightly higher at 136 mm (5.4 in) over 14 days, while July sees 123 mm (4.9 in) spread across 18 days, making both months relatively wet with consistent humidity levels around 83%. For more details on the climate during July, you can check Ascona weather in July.
In comparing the weather between September and August, it is evident that September experiences significantly cooler temperatures, with a minimum of -1°C (31°F) and a maximum of 23°C (74°F), compared to August's cooler minimum of 7°C (45°F) and a warmer maximum of 28°C (82°F). While both months receive substantial rainfall, September has slightly less precipitation at 136 mm (5.4 in) over 14 days, compared to August's 169 mm (6.6 in) over 13 days. Additionally, September's humidity is slightly higher at 83%, while August remains at a lower 80%. For more detailed insights, you can check Ascona weather in August.
In September, temperatures generally range from a minimum of -1°C (31°F) to a pleasant maximum of 23°C (74°F), with an average of 13°C (55°F). The month experiences 136 mm (5.4 in) of precipitation over 14 days, accompanied by a relative humidity of 83%. In contrast, October sees a slight decrease in maximum temperatures, with values reaching up to 21°C (69°F) and an average of 8°C (47°F). However, it experiences significantly higher precipitation at 242 mm (9.5 in) over just 12 days and a rise in humidity to 90%. For more detailed information on October weather, visit Ascona weather in October.
As September transitions into November, the weather exhibits a notable shift. September typically boasts milder temperatures, with averages around 13°C (55°F) and maximums reaching up to 23°C (74°F), while November brings a significant drop, with averages plummeting to 3°C (38°F) and max temperatures capping at 15°C (59°F). Additionally, precipitation increases in November, totaling 168 mm (6.6 in) over 13 days, compared to September's 136 mm (5.4 in) across 14 days. Humidity rises as well, reaching 88% in November, compared to 83% in September. For more specific insights, check out Ascona weather in November.
In September, the weather is typically milder, with temperatures ranging from a minimum of -1°C (31°F) to a comfortable maximum of 23°C (74°F), and an average of 13°C (55°F). The month experiences significant rainfall, with about 136 mm (5.4 in) spread over 14 days, and humidity levels at 83%. In contrast, December brings colder conditions, with temperatures dropping to a minimum of -13°C (10°F), averaging around -1°C (31°F), and peaking at only 9°C (49°F). Precipitation decreases slightly to 119 mm (4.7 in) over 12 days, accompanied by higher humidity at 90%. For more details on what to expect, check Ascona weather in December.
As September unfolds in Ascona, the weather presents a notable shift from the summer heat, with temperatures ranging from mild to cool. The month often greets visitors with refreshing breezes and an occasional chill, particularly in the early mornings and late evenings. Although rainfall increases with about half the month experiencing precipitation, it offers a much-needed contrast to the summer dryness, contributing to the lush landscapes of the area. The high humidity can make the air feel heavier, but it also infuses the scenery with a vibrant life. Overall, September is a transitional period, making it an ideal time for those who appreciate a blend of autumn's subtle beauty and lingering warmth. To explore further insights about the weather, visit Ascona Climate.