Last updated: August 27, 2025
September in Lausanne, Switzerland offers a delightful blend of mild temperatures and scenic beauty. With a maximum temperature reaching 27°C (81°F) and an average of 16°C (61°F), this month perfectly balances warmth and coolness. However, the weather can be unpredictable, as 75 mm (2.9 in) of precipitation typically falls over 11 days, contributing to the region's lush landscapes. The humidity level, around 81%, adds a refreshing touch to the crisp autumn air. Whether you’re exploring local parks or savoring the vibrant cultural scene, September is a captivating time to experience Lausanne's charm.
In September, Lausanne experiences a delightful transition into autumn, showcasing mild and comfortable temperatures. With a minimum of 6°C (43°F) and a pleasant average of 16°C (61°F), residents and visitors can enjoy the great outdoors without the sweltering heat of summer. As the month progresses, temperatures peak at a cozy 27°C (81°F), perfect for leisurely strolls along the picturesque shores of Lake Geneva. This moderate climate not only invites outdoor activities but also offers a gorgeous backdrop as the foliage begins to shift into vibrant autumn hues, making September a charming time to explore this Swiss gem.
In September, Lausanne experiences a moderate dip in precipitation, with 75 mm (2.9 in) of rain spread over approximately 11 days. This trend indicates a transition from the wetter summer months, as both May and June recorded significantly higher rainfall, at 142 mm (5.6 in) and 103 mm (4.1 in) respectively. By September, the region begins to prepare for the cooler months, with falling precipitation levels that suggest a gradual shift towards autumn. This reduction not only alleviates the intense wetness felt during the summer but also paves the way for a more temperate climate in the upcoming fall season. As clouds linger, the charm of Lausanne continues to captivate, even as the rains begin to taper off.
In Lausanne, Switzerland, September brings a slight uptick in humidity to 81%, after a summer marked by a more comfortable 77% in August. This month marks a shift as the warm, dry summer transitions into the dampness of autumn. While September's levels are elevated compared to the previous month, they remain lower than the winter months, where humidity consistently hovers around 89% or higher. Notably, the overall trend indicates that humidity levels in Lausanne are at their peak in the colder months, often reaching a maximum of 91% in December and January. As the year progresses, September serves as a bridge, hinting at the forthcoming chill while still holding onto the remnants of summer warmth.
As September rolls into Lausanne, Switzerland, the UV Index reflects a shift from the peak summer levels, settling at a moderate to high rating of 7. This signifies a healthy warning for sun exposure, as individuals can expect a burn time of approximately 25 minutes under the midday sun. Notably, this month sees a decrease from the very high indices recorded in the heart of summer, with August and July both hitting 9. However, the high UV Index remains significant, underscoring the need for sun protection especially during outdoor activities. As the season transitions into autumn, awareness of these UV levels is crucial for maintaining skin health—even as the sun begins to set earlier. For detailed updates and further insights, visit the Lausanne UV Index.
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As summer gently transitions to autumn, September in Lausanne enjoys a remarkable array of 330 hours of sunshine. This month, while cooler than the peak summer days of July and August, still captures the lingering warmth of the season. The sunlight begins to mellow after July's maximum of 418 hours, but September maintains a commendable brightness that significantly surpasses the winter months, such as January's mere 167 hours. The steady decline in sunlight hours, typical as the year progresses, is evident, yet September offers a vibrant mix of warmth and light, inviting both residents and visitors to relish the beauty of the city's late summer charm before the crispness of fall fully sets in.
In Lausanne, Switzerland, the likelihood of sunny weather shows some intriguing trends as the year progresses. After a winter of low probabilities, with just 15% sunshine in January, the chances gradually increase to a peak of 51% in April. As spring transitions into summer, the likelihood stabilizes around 33% to 42% for the warmer months. However, September sees a slight dip to 36%, marking a gradual shift toward autumn. This reflects a seasonal decline in sunny days, yet the month still offers a decent opportunity to enjoy the last rays of summer before the colder weather sets in. Overall, while September may not boast the highest chances of sunshine, it maintains a relatively favorable outlook compared to the winter months.
As September unfolds in Lausanne, Switzerland, the daylight begins to wane, presenting approximately 12 hours of sunlight—a gentle transition from the vibrant summer months. After basking in the 15-hour daylight of May through July, the days gradually shorten, dipping from 14 hours in August to 12 this month. This subtle decrease signals the onset of autumn, where the comforting warmth of summer gives way to cooler, crisper air. While September’s daylight is still generous compared to the winter months, which see as little as 8 hours in December, it serves as a reminder of the cyclical nature of the seasons, encouraging residents to savor the lingering sunlight before the days grow even shorter.
As September unfolds in Lausanne, Switzerland, the air begins to whisper of autumn, accompanied by a gentle breeze that sees the average wind speed dip to 1.3 m/s (3 mph). This marks a continuation of the subtle downward trend noted throughout the summer months, where winds have lingered at a consistent 3 mph since July. Although September introduces a hint of chill, its breezy temperament is not unlike the earlier months of the year, hovering around 1.7 to 1.9 m/s from January to April. The transition from summer's warmth to autumn's embrace is not just felt in the temperature but also in the air movement, setting a serene backdrop for the month ahead.
Weather in Lausanne varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Lausanne, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present notably contrasting weather conditions. In September, temperatures range from a minimum of 6°C (43°F) to a comfortable maximum of 27°C (81°F), with an average of 16°C (61°F). The month typically sees around 75 mm (2.9 in) of precipitation across 11 days, and humidity levels hover at 81%. In stark contrast, January experiences much colder temperatures, with a minimum of -7°C (20°F) and a maximum of 14°C (57°F), averaging just 3°C (37°F). Precipitation increases to 116 mm (4.6 in) over the same number of days, and humidity rises slightly to 91%. For more details on January weather in Lausanne, you can visit Lausanne weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a minimum of 6°C (43°F) to a pleasant maximum of 27°C (81°F), with an average of 16°C (61°F). The month is characterized by 75 mm (2.9 in) of precipitation over 11 days, accompanied by a relatively high humidity level of 81%. In stark contrast, February experiences colder conditions, with temperatures plunging to a minimum of -10°C (15°F) and only reaching a maximum of 16°C (61°F), averaging just 4°C (40°F). Precipitation increases to 93 mm (3.7 in) over the same 11 days, and humidity rises slightly to 89%. For more details on the chilly atmosphere of February, you can check Lausanne weather in February.
The weather in September and March displays distinct differences, reflecting the transition between late summer and early spring. In September, temperatures range from a mild 6°C (43°F) at night to a warm 27°C (81°F) during the day, with an average of 16°C (61°F). This month experiences relatively moderate precipitation levels of 75 mm (2.9 in) over 11 days, coupled with a humidity of 81%.
In contrast, March sees colder temperatures, with a minimum of -9°C (17°F) and a maximum of 20°C (68°F), resulting in an average of just 6°C (43°F). It's also wetter, with approximately 111 mm (4.4 in) of rainfall spread over 14 days and slightly higher humidity at 87%. For more detailed insights into the weather patterns for March, you can check Lausanne weather in March.
September and April present a striking contrast in weather conditions. In September, temperatures range from a minimum of 6°C (43°F) to a maximum of 27°C (81°F), with an average of 16°C (61°F), making it a generally warmer month. The average humidity is slightly lower at 81% and the month sees around 75 mm (2.9 in) of precipitation over approximately 11 days. In contrast, April experiences cooler temperatures, with a minimum of -2°C (28°F) and a maximum of 24°C (76°F), averaging just 9°C (49°F). This month has higher humidity levels at 84% and slightly less precipitation, totaling 59 mm (2.3 in) over about 9 days. For more information on the specific conditions, visit Lausanne weather in April.
September and May present distinct contrasts in weather patterns. In September, temperatures range from a minimum of 6°C (43°F) to a maximum of 27°C (81°F), with an average of 16°C (61°F). The month sees 75 mm (2.9 in) of precipitation over 11 days, accompanied by a humidity level of 81%. In comparison, May experiences slightly cooler temperatures, with a minimum of 1°C (34°F) and a maximum of 26°C (79°F), averaging around 12°C (55°F). However, it is wetter, with 142 mm (5.6 in) of precipitation spread over 15 days and a similar humidity of 80%. For more detailed insights, check out Lausanne weather in May.
September and June exhibit notable differences in weather characteristics. In September, minimum temperatures drop to around 6°C (43°F), with an average of 16°C (61°F) and a maximum reaching 27°C (81°F). The month experiences about 75 mm (2.9 in) of precipitation over 11 days, with relative humidity at 81%. In contrast, June tends to be warmer, with minimum temperatures around 8°C (47°F), an average of 17°C (64°F), and highs soaring up to 33°C (91°F). The total precipitation in June is higher at 103 mm (4.1 in) over 13 days, along with a slightly elevated humidity level of 82%. For more details about June weather, you can check Lausanne weather in June.
When comparing the weather in September to that of July, notable differences emerge. September features cooler temperatures, ranging from a minimum of 6°C (43°F) to a maximum of 27°C (81°F), with an average of 16°C (61°F). In contrast, July is significantly warmer, with temperatures fluctuating between 11°C (53°F) and 34°C (94°F), resulting in a higher average of 19°C (67°F). Additionally, September experiences less precipitation at 75 mm (2.9 in) over 11 days, while July sees more rainfall at 106 mm (4.2 in) over 13 days. Humidity levels remain similar, with September at 81% and July slightly higher at 82%. For more detailed insights, you can check Lausanne weather in July.
In comparing the weather of September and August, September presents cooler temperatures, with a minimum of 6°C (43°F) and a maximum of 27°C (81°F), as opposed to August's milder range, which features a minimum of 9°C (48°F) and a peak of 31°C (89°F). While both months see precipitation on 11 days, September experiences less overall rainfall at 75 mm (2.9 in) compared to August's 101 mm (4.0 in). Additionally, September's higher humidity at 81% contrasts with August's 77%, contributing to a more noticeable sense of dampness as summer wanes. For more detailed insights, you can refer to Lausanne weather in August.
September offers a more temperate climate with an average temperature of 16°C, peaking at 27°C, while October sees a noticeable drop with an average of 12°C and a maximum of 23°C. Precipitation increases from 75 mm in September to 104 mm in October, contributing to a wetter month with one additional day of rain. The humidity also rises from 81% in September to 89% in October, making the air feel even more crisp. For a closer look at what to expect, check out Lausanne weather in October.
September boasts a milder climate with average temperatures around 16°C (61°F), peaking at 27°C (81°F), making it ideal for enjoying the last days of warm weather. In contrast, November sees a significant drop in temperatures, with an average of just 7°C (45°F) and chilly lows of -2°C (29°F). While both months experience a similar number of rainy days, November is wetter overall, receiving 98 mm (3.8 in) of precipitation compared to September's 75 mm (2.9 in). Additionally, humidity levels increase in November to 89%, creating a more brisk atmosphere. For those interested in detailed November weather trends, check out Lausanne weather in November.
September and December present contrasting weather patterns. In September, temperatures range from a mild minimum of 6°C (43°F) to a pleasant maximum of 27°C (81°F), with an average of 16°C (61°F). The month experiences a total precipitation of 75 mm (2.9 in) over 11 days, accompanied by relatively high humidity at 81%. In stark contrast, December sees much colder temperatures, with a minimum of -4°C (25°F) and a maximum of 13°C (55°F), averaging just 4°C (39°F). Rainfall significantly increases to 186 mm (7.3 in) across 17 days, and humidity rises slightly to 91%. Those interested in learning more about December weather can visit Lausanne weather in December.
As September arrives in Lausanne, the weather begins to transition, offering a delightful blend of warm days and cool nights. With maximum temperatures reaching a comfortable 27°C and an average of 16°C, this month stands out with its inviting climate, perfect for enjoying the outdoors. Although rainfall is common, with about 11 days experiencing precipitation, the humidity levels at 81% create a refreshing atmosphere. Unlike the scorching summer months, September provides a more moderate experience, allowing visitors and locals alike to relish in the stunning autumnal scenery. For more insights on what to expect from Lausanne's weather throughout the year, check out Lausanne Climate.