Last updated: August 27, 2025
Mendrisio, Switzerland in September offers a delightful mix of warm days and cool evenings. With maximum temperatures reaching 29°C (84°F) and an average of 19°C (66°F), the weather invites outdoor adventures. However, the charm of the month is often accompanied by occasional rainfall, totaling 146 mm (5.8 in) over approximately 11 days, contributing to the region's lush scenery. Humidity levels average around 74%, adding a touch of softness to the air. Embrace the beauty of fall as nature transitions, making September a captivating time to explore Mendrisio.
September in Mendrisio, Switzerland, marks a delightful transition into autumn, characterized by mild and comfortable temperatures. As summer fades, the minimum temperature hovers around 8°C (46°F), allowing for refreshing mornings, while the average rises to a pleasant 19°C (66°F) during the day. Highs can reach a welcoming 29°C (84°F), providing plenty of opportunities to enjoy the lush scenery. This month stands out for its balanced climate, combining the warmth of summer with the crispness of fall—ideal for outdoor activities and savoring the vibrant autumn foliage. As the days become shorter, the beauty of Mendrisio transforms, drawing visitors to experience the charm of this picturesque Swiss town.
In September, Mendrisio experiences a notable increase in precipitation, receiving 146 mm (5.8 in) over the course of the month. This uptick marks a continuation of the wet trend seen throughout the summer months, with rainfall peaking in June and July. As the days grow shorter, the precipitation is spread across 11 rainy days, slightly less than the more rain-soaked months of May and June. However, September's totals still reinforce its position as one of the wetter months of the year, creating a lush, vibrant landscape that prepares the region for the coming autumn. This consistent rainfall reflects Mendrisio's characteristic transition into the cooler seasons, where nature thrives in dramatic hues and scents.
As autumn approaches in Mendrisio, Switzerland, September sees a return to a more comfortable humidity level of 74% after the summer months. The year began with a noticeably high humidity, peaking at 88% in January and gradually decreasing to its lowest point in July with 67%. This trend of decreasing humidity continued into August, establishing a dry summer ambiance that many enjoy. However, September marks a shift, as the air becomes more humid once again, paving the way for October's return to a higher 87% humidity. This fluctuation, characteristic of the region's climate, highlights the transition into the wetter months ahead while still offering a brief respite of moderate humidity in late summer.
In September, Mendrisio experiences a notable transition in its UV Index, reflecting the approach of autumn. With a UV Index of 6, the exposure category is classified as high, requiring a burn time of 25 minutes before skin damage can occur. This marks a gradual decline from the intense values seen in the summer months, where the index peaked at 9 during July and June, demanding quick attention to sun protection. As outdoor enthusiasts savor the lingering warmth of early fall, it's essential to remain vigilant about sun safety, especially as the sun's intensity begins to taper off. For a full overview of UV levels throughout the year, check out Mendrisio UV Index.
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September in Mendrisio, Switzerland, boasts an impressive 335 hours of sunshine, marking a vibrant transition as summer draws to a close. This month continues the trend established in the summer, with sunlight peaking in July at 427 hours and gradually tapering off but still offering plenty of brightness. The slight decline from August's 391 hours highlights the seasonal shift, yet September remains significantly sunnier compared to the winter months ahead, such as November's 211 hours. Embracing the warm glow of early autumn, Mendrisio invites visitors to enjoy the breathtaking landscapes bathed in golden light, making it a perfect time to experience the town's charm before the shorter days settle in.
As summer transitions into autumn, September in Mendrisio, Switzerland experiences a notable shift in weather patterns. With a 44% chance of sun, this month showcases a blend of lingering warmth from summer and the crispness of fall. Despite a drop from the sunnier 55% in August, September maintains a respectable probability of clear skies, typical of the early autumn period. This trend highlights a gradual shift toward less sunny weather, yet still provides plenty of opportunities for enjoying the picturesque landscapes before winter sets in. Whether you’re exploring the charming streets or hiking the surrounding hills, you can expect a fair share of delightful sunshine amid the changing leaves.
As summer transitions into autumn, September in Mendrisio, Switzerland, brings a gentle decline in daylight, offering about 12 hours of sun—a noteworthy shift from the peak summer months. This gradual reduction in daylight follows a pattern established through the year, starting with shorter days in January that span just 9 hours, increasing steadily until June and July’s glorious 15 hours. Following the summer solstice, daylight begins to taper off, with August dropping to 14 hours and September marking a more significant change as evening shadows grow longer. This trend showcases not only the rhythm of the seasons but also invites residents and visitors alike to savor the warmth of the fading summer sun before the crispness of fall sets in.
As summer gives way to autumn, September's winds in Mendrisio, Switzerland, reflect a gentle shift, with average wind speeds dipping to 1.5 m/s (3 mph). This marks the month's status as the calmest of the year, following a slight decline from the preceding months. The trend showcases a gradual cooling as the seasons change: from the lively breezes of spring and the mild currents of summer, the winds soften in September, hinting at the peaceful and serene atmosphere that characterizes the onset of fall. With the leaves beginning to shift colors, the tranquil winds become a perfect companion for leisurely strolls through the picturesque streets of Mendrisio.
Weather in Mendrisio varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Mendrisio, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather. September typically enjoys milder temperatures, with averages around 19°C (66°F) and highs reaching up to 29°C (84°F), making it a warm and pleasant month. However, it also sees substantial rainfall, averaging 146 mm (5.8 in) over 11 days, coupled with a humidity level of 74%. In comparison, January is much cooler, with average temperatures dropping to 4°C (39°F) and maximums only reaching 16°C (60°F). This winter month experiences significantly less precipitation, with only 42 mm (1.7 in) over just 6 days, though humidity is higher at 88%. For a closer look at January weather specifics, you can refer to Mendrisio weather in January.
September and February present starkly contrasting weather experiences. In September, temperatures range from a mild 8°C (46°F) at night to a warm 29°C (84°F) during the day, with an average of 19°C (66°F). The month sees a fair amount of rain, with 146 mm (5.8 in) spread over 11 days, and humidity sits at a comfortable 74%. In contrast, February is much cooler, with temperatures dipping as low as -7°C (19°F) at night and peaking at 20°C (68°F) during the day, averaging only 6°C (43°F). Precipitation is significantly lower at 46 mm (1.8 in) over just 7 days, but humidity is slightly higher at 81%. For a more detailed look at February weather, check out Mendrisio weather in February.
In comparing the weather of September and March, September tends to be significantly warmer, with average temperatures ranging from a minimum of 8°C (46°F) to a maximum of 29°C (84°F). In contrast, March experiences cooler conditions, with temperatures ranging from -5°C (23°F) to a maximum of 23°C (74°F). Precipitation is also more abundant in September, totaling 146 mm (5.8 in) over 11 days, while March sees less rain at 88 mm (3.5 in) across 9 days. Despite the difference in precipitation, humidity levels remain relatively similar, with September at 74% and March slightly higher at 76%. For more detailed insights, you can check Mendrisio weather in March.
The weather in September is generally warmer than in April, with average temperatures ranging from a minimum of 8°C (46°F) to a maximum of 29°C (84°F), compared to April's 0°C (33°F) minimum and 25°C (78°F) maximum. September also experiences higher average temperatures, making it feel more like the tail end of summer, while April has cooler temperatures that signify the arrival of spring. In terms of precipitation, September has slightly more rainfall, totaling 146 mm (5.8 in) over 11 days, compared to April's 124 mm (4.9 in) over the same number of days. Humidity levels are similar, with September at 74% and April slightly higher at 77%. For specific insights into April weather, you can check out Mendrisio weather in April.
When comparing the weather in September and May, both months showcase similar humidity levels at 74%, but the temperatures tell a different story. September enjoys an average temperature of 19°C (66°F) with highs reaching 29°C (84°F), while May has a slightly cooler average of 17°C (63°F), peaking at 32°C (89°F). Precipitation is relatively consistent, with September receiving 146 mm (5.8 in) over 11 days and May slightly less at 143 mm (5.6 in) across 16 days. For a closer look at May's conditions, you can refer to Mendrisio weather in May.
In comparing the weather of September and June, we observe notable differences in temperature and precipitation. September brings a milder climate with average temperatures ranging from a minimum of 8°C (46°F) to a maximum of 29°C (84°F) and an average of 19°C (66°F). In contrast, June experiences warmer conditions, with temperatures reaching a minimum of 12°C (55°F) and soaring up to 37°C (100°F), averaging around 22°C (72°F). Both months see a fair amount of rainfall, with September receiving 146 mm (5.8 in) over 11 days and June experiencing slightly more precipitation at 161 mm (6.4 in) over 12 days. Humidity levels are similar, with September at 74% and June at 71%. For more detailed insights about June weather in Mendrisio, check out Mendrisio weather in June.
In comparing the weather of September and July, September tends to be cooler, with average temperatures ranging from a minimum of 8°C (46°F) to a maximum of 29°C (84°F), while July boasts warmer temperatures, with averages between 14°C (57°F) and 34°C (94°F). Additionally, September experiences more precipitation, with 146 mm (5.8 in) over 11 days, compared to July's 164 mm (6.5 in) over 14 days. Humidity levels are slightly higher in September at 74%, while July maintains a more comfortable 67%. For more detailed insights into July weather in Mendrisio, you can check Mendrisio weather in July.
In comparing the weather between August and September, we see a noticeable shift towards cooler temperatures and increased precipitation. August experiences warmer conditions with temperatures ranging from a minimum of 14°C (58°F) to a maximum of 34°C (93°F), boasting an average of 24°C (75°F). In contrast, September's temperatures dip to a minimum of 8°C (46°F) and maximum of 29°C (84°F), with an average of 19°C (66°F). Additionally, September has slightly higher precipitation at 146 mm (5.8 in) over 11 days compared to August's 136 mm (5.3 in) over 13 days, while September also features higher humidity at 74%, compared to August's 64%. For more details on August weather, you can visit Mendrisio weather in August.
September and October present noticeable shifts in weather patterns. In September, temperatures range from a minimum of 8°C (46°F) to a maximum of 29°C (84°F), with an average of 19°C (66°F). The month sees approximately 146 mm (5.8 in) of precipitation over 11 days, accompanied by a humidity level of 74%. In contrast, October experiences slightly cooler temperatures, with a minimum of 6°C (43°F) and a maximum of 26°C (80°F), leading to an average temperature of 14°C (58°F). Moreover, October has slightly more precipitation at 152 mm (6.0 in) but over fewer days (8), and humidity rises to 87%. For more details on October weather, you can check Mendrisio weather in October.
September and November present contrasting weather patterns. September enjoys milder temperatures, ranging from a minimum of 8°C (46°F) to a maximum of 29°C (84°F), with an average of 19°C (66°F). In contrast, November sees much cooler conditions, with temperatures dipping to a minimum of 0°C (32°F) and an average of only 9°C (49°F). Precipitation is relatively high in both months, with September receiving 146 mm (5.8 in) over 11 days and November slightly wetter at 169 mm (6.7 in) over 12 days. Additionally, November's humidity climbs to 88%, compared to September's 74%, contributing to a distinctly chillier feel as autumn sets in. For more details, check out Mendrisio weather in November.
September and December present contrasting weather patterns. In September, temperatures range from a milder minimum of 8°C (46°F) to a warm maximum of 29°C (84°F), with an average of 19°C (66°F). The month sees considerable precipitation, totaling 146 mm (5.8 in) over about 11 days and a relatively comfortable humidity level of 74%. In stark contrast, December experiences much colder conditions, with temperatures dropping to a minimum of -3°C (28°F) and an average of just 5°C (41°F), peaking at 14°C (58°F). Precipitation is lower at 94 mm (3.7 in) spread over 8 days, but the humidity is higher at 85%. To explore more about December's weather, check out Mendrisio weather in December.
As September rolls in, Mendrisio experiences a delightful transition from the warmth of summer to the crisp embrace of autumn. The temperatures are moderate, striking a harmonious balance that makes outdoor activities enjoyable. While the maximum warmth is still reminiscent of summer, the evenings dip noticeably cooler—ushering in a refreshing chill. September also sees an increase in precipitation with around eleven rainy days, contributing to the region's lush landscapes. This month is characterized by a comfortable humidity level, creating a unique blend of freshness that's distinct from the hotter summer months. To learn more about what to expect throughout the year, visit Mendrisio Climate.