Last updated: August 27, 2025
September in Interlaken, Switzerland, offers a delightful blend of early autumn charm and spectacular scenery. With maximum temperatures reaching 23°C (73°F) and an average of 11°C (53°F), the weather is pleasantly mild, though it can dip to a refreshing 0°C (32°F) at night. Visitors can expect a total precipitation of 124 mm (4.9 in), spread across approximately 14 rainy days, which contributes to the lush, vibrant landscapes. The humidity levels hover around 83%, enhancing the cool mountain air and making it an ideal time for exploration and outdoor activities amidst the stunning backdrop of the Swiss Alps.
September in Interlaken, Switzerland, heralds the arrival of autumn, marked by a noticeable shift in temperatures. The minimum temperature settles around 0°C (32°F), while the average climbs to 11°C (53°F)—a gentle embrace before the winter chill sets in. With a comfortable maximum of 23°C (73°F), this month offers pleasant days ideal for exploring the stunning alpine landscapes. This transition from the warmth of summer, where August hovers around 15°C (59°F) and peaks at 28°C (82°F), lays the groundwork for the cooler days ahead. As September unfolds, the crisp air begins to hint at the changes to come, making it a perfect time for outdoor adventures amidst the breathtaking scenery.
In September, Interlaken experiences a notable shift in weather patterns, with precipitation totaling 124 mm (4.9 in) spread across 14 rainy days. This level of rainfall aligns closely with the trends observed in the summer months, maintaining a robust amount of moisture before transitioning into the drier autumn season. Notably, September's precipitation is slightly lower than that of the preceding months of July and August, which saw significant rainfall of 219 mm (8.6 in) and 203 mm (8.0 in), respectively. As autumn approaches, the days of rain begin to decrease, signaling the gradual shift toward cooler, more stable weather, which is characteristic of October. Overall, the patterns indicate a lush late summer landscape gradually making way for fall, as the vibrant colors of Interlaken's surroundings intensify with each rainfall.
As autumn begins to unfold in Interlaken, Switzerland, September brings a noticeable shift in humidity levels, settling at 83%. This figure closely mirrors the preceding months of July and August, which also hovered around the low 80s, suggesting a mild transition as summer wanes. However, this month marks a slight increase compared to August's 80%, indicating the impending dampness associated with the encroaching fall season. The trend of gradually rising humidity continues leading into October, where levels spike again to 90%. Overall, September serves as a bridge between the relatively pleasant summer months and the wetter, more humid conditions of late autumn.
As summer fades and autumn approaches, September in Interlaken, Switzerland, sees a noticeable drop in UV intensity, with the UV Index at 7, categorizing exposure as high. This is a transition from the intense highs of June and July, where the UV Index peaked at 10, demanding very short burn times of just 15 minutes. In September, while the sun still exerts a strong influence, visitors can enjoy a safer 25 minutes of sun exposure before needing protection. As the days grow shorter and the season changes, it's essential to remain mindful of UV levels. For more detailed insights into sun safety and UV trends in this picturesque region, visit Interlaken UV Index.
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As summer gracefully transitions to autumn, September in Interlaken, Switzerland, offers a delightful balance of warmth and sunlight, boasting 322 hours of sunshine. This month marks a gentle decline from the peak of 416 hours in July, illustrating the gradual ebb of summer's brilliance. Yet, September still shines brighter than the earlier months of the year, showcasing a significant leap from just 169 hours in January. As the landscape transforms with autumn hues, visitors can relish in the soft golden light that paints the Swiss Alps, making it a picturesque time for outdoor adventures before the colder days ahead. Whether hiking through vibrant trails or exploring charming local cafes, the lingering sunshine invites everyone to savor the beauty of this enchanting season.
In the picturesque locale of Interlaken, September offers a moderate chance of sunshine, sitting at around 38%. This percentage reflects a steadiness typical of late summer, as the likelihood of sunny days remains akin to the preceding months of August. As the seasons transition into the fall, the chance of sun doesn’t see significant fluctuations, suggesting that while sunshine is not guaranteed, outdoor enthusiasts can still relish in the beauty of the Alps under mostly clear skies. With October bringing a slight uptick to 43%, those visiting in September can still enjoy a vibrant mix of lush landscapes and the changing hues of autumn, making it a charming time to explore.
As summer transitions into autumn, September in Interlaken, Switzerland experiences a noticeable shift in daylight, with approximately 12 hours of sunlight each day. This month marks a gradual decrease from the 15 hours enjoyed in the peak of summer, signaling the onset of shorter days. Following a vibrant summer, where daylight was abundant in the months of June, July, and August, the descent into September retains a lingering warmth while foreshadowing the shorter daylight hours of fall. As nature begins its transition into the rich colors of autumn, visitors can still revel in a generous amount of daylight, making it an ideal time for outdoor adventures and breathtaking scenic views.
As summer transitions to autumn in Interlaken, September brings a gentle breeze, with an average wind speed of 1.3 m/s (3 mph), often mirroring the calmness of the preceding months. This slight dip in wind speed reflects a trend seen throughout the summer, where July and August maintain similar whisper-like currents. Interestingly, while spring months like April and May show slightly higher gusts, they are still relatively mild compared to the brisker winds of late autumn and winter. As temperatures begin to cool, the soft September winds offer a perfect backdrop for those exploring the stunning landscapes of the Swiss Alps, evoking a serene and inviting atmosphere for both adventure and relaxation.
Weather in Interlaken varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Interlaken, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January offer starkly contrasting weather conditions. In September, temperatures range from a minimum of 0°C (32°F) to a pleasant maximum of 23°C (73°F), with an average of 11°C (53°F). The month experiences around 124 mm (4.9 in) of precipitation over 14 days and has a humidity level of 83%. Conversely, January is much colder, with temperatures dropping significantly, from a minimum of -19°C (-1°F) to a maximum of 9°C (48°F), averaging -3°C (26°F). Despite similar precipitation levels of 123 mm (4.9 in) over 12 days, January's humidity is slightly higher at 92%. For a detailed look at January's conditions, you can explore Interlaken weather in January.
September and February present starkly contrasting weather patterns. In September, temperatures range from a minimum of 0°C (32°F) to a pleasant maximum of 23°C (73°F), with an average of 11°C (53°F). This month also experiences 124 mm (4.9 in) of precipitation over 14 days, coupled with a humidity level of 83%. In contrast, February is much colder, with temperatures dipping to a minimum of -18°C (-1°F) and only reaching up to 14°C (58°F), resulting in an average of -1°C (31°F). Precipitation is slightly lower at 103 mm (4.0 in) over 11 days, and humidity is higher at 89%. For more details on winter conditions, check out Interlaken weather in February.
In comparing the weather between September and March, we can see notable differences in temperature and conditions. September features a minimum temperature of 0°C (32°F) and an average of 11°C (53°F), peaking at 23°C (73°F), while March is significantly colder, with minimum temperatures dropping to -23°C (-9°F) and an average of only 2°C (36°F), maxing out at 16°C (60°F). Despite both months receiving similar amounts of precipitation—124 mm (4.9 in) in September and 125 mm (4.9 in) in March—the number of rainy days is slightly higher in March, with precipitation occurring on 15 days compared to 14 days in September. Additionally, March tends to be more humid, with relative humidity at 87% versus 83% in September. For a detailed look at what to expect, check Interlaken weather in March.
September and April exhibit distinct differences in weather patterns. September typically experiences milder temperatures, with minimums around 0°C (32°F) and averages of 11°C (53°F), while April can be chillier, with minimums dropping to -12°C (10°F) and an average of only 5°C (42°F). Both months see considerable precipitation, with September averaging 124 mm (4.9 in) over 14 days compared to April's 94 mm (3.7 in) over 12 days. Additionally, humidity remains high in both months, at 83% in September and slightly higher at 84% in April. For a closer look at the specific conditions, check out Interlaken weather in April.
In comparing the weather of September and May, it is evident that both months present a range of temperatures but with notable differences. September typically experiences milder temperatures, with averages around 11°C (53°F) and maximums reaching up to 23°C (73°F), while May has a colder average of 9°C (48°F) but can peak at a warmer 25°C (78°F). Additionally, May tends to be rainier, with a higher precipitation level of 182 mm (7.2 in) over 19 days compared to September's 124 mm (4.9 in) over 14 days. Both months have relatively high humidity, but September is marginally more humid at 83% compared to May's 80%. For a closer look at May's weather, you can check out Interlaken weather in May.
When comparing the weather in September and June, it's clear that June is generally warmer and wetter. In June, temperatures range from a minimum of 1°C (34°F) to a maximum of 29°C (85°F), with an average of 14°C (57°F). In contrast, September sees cooler temperatures, with a minimum of 0°C (32°F) and a maximum of 23°C (73°F), averaging 11°C (53°F). Additionally, June experiences higher precipitation, totaling 225 mm (8.9 in) over 18 days, compared to September's 124 mm (4.9 in) over 14 days. Humidity levels remain similar, with June at 82% and September at 83%. For more detailed insights, you can visit Interlaken weather in June.
In comparing the weather between September and July, it is clear that July typically experiences warmer temperatures, with a minimum of 5°C (41°F) and a maximum of 29°C (84°F), contrasted with September’s cooler range of 0°C (32°F) to 23°C (73°F). While the average temperature in July is 15°C (60°F), September's average is considerably lower at 11°C (53°F). Additionally, July sees more precipitation, averaging 219 mm (8.6 in) over 18 days, compared to September's 124 mm (4.9 in) over 14 days. Despite the increased rainfall in July, both months maintain the same humidity level of 83%. For a detailed exploration of July's weather in particular, check out Interlaken weather in July.
In comparing the weather patterns of September and August, it is clear that September tends to be cooler and wetter. September experiences a minimum temperature of 0°C (32°F), with an average of 11°C (53°F) and a maximum of 23°C (73°F). In contrast, August sees milder temperatures, ranging from a minimum of 5°C (41°F) to a maximum of 28°C (82°F), with an average of 15°C (59°F). Precipitation levels are also noteworthy, as September has 124 mm (4.9 in) over 14 days, while August receives a heavier rainfall of 203 mm (8.0 in) across 18 days. Humidity levels remain relatively similar, with September at 83% and August at 80%. For more specific weather details, you can check Interlaken weather in August.
In September, the weather begins to cool down as autumn sets in, with temperatures ranging from a minimum of 0°C (32°F) to a maximum of 23°C (73°F) and an average of 11°C (53°F). The month sees considerable precipitation, totaling 124 mm (4.9 in) over 14 days, while the humidity hovers around a relatively high 83%.
As October arrives, temperatures drop further, with minimums dipping to -4°C (26°F) and an average temperature of 7°C (45°F). The maximum temperature is slightly lower at 19°C (67°F). Rainfall increases slightly to 138 mm (5.4 in) across 13 days, and humidity rises to 90%. This shift hints at the deepening transition into winter. For more information, you can check Interlaken weather in October.
In comparing the weather of September and November, September boasts milder temperatures with average highs reaching 23°C (73°F), while November presents a notable drop in temperatures, averaging around 2°C (35°F) with a maximum of 18°C (64°F). Additionally, September experiences more precipitation, totaling 124 mm (4.9 in) over 14 days, compared to November’s 97 mm (3.8 in) across 13 days. Humidity levels are slightly higher in November at 88%, compared to September's 83%. For a more detailed look at November weather in Interlaken, you can visit Interlaken weather in November.
September and December present stark contrasts in weather characteristics. In September, temperatures range from a minimum of 0°C (32°F) to a maximum of 23°C (73°F), with an average of 11°C (53°F). The month experiences 124 mm (4.9 in) of precipitation over 14 days, while humidity is relatively high at 83%. In contrast, December brings much colder conditions, with temperatures dipping as low as -13°C (8°F) and averaging around -2°C (29°F), peaking at 9°C (49°F). This month sees increased precipitation, totaling 175 mm (6.9 in) over 17 days, and humidity rises slightly to 90%. For a closer look at December's weather specifics, you can refer to Interlaken weather in December.
As September unfolds in Interlaken, it brings a distinct shift in weather patterns compared to the summer months. With temperatures gradually cooling, the warmth of earlier months gives way to crisp mornings and mild afternoons, making it an ideal time for outdoor adventures. However, be prepared for a fair bit of rain, as this month sees increased precipitation and high humidity levels, adding to the freshness in the air. Whether you're enjoying the vibrant autumn foliage or exploring the scenic landscapes, September offers a unique charm that sets it apart from the rest of the year. For a deeper understanding of what to expect, check out Interlaken Climate.