September Weather in Grindelwald, Switzerland

Last updated: August 27, 2025

September in Grindelwald, Switzerland offers a captivating tapestry of weather, marked by a maximum temperature of 18°C (65°F) and a cooler average of 6°C (44°F). As autumn begins to settle in, temperatures can dip as low as -8°C (17°F), bringing a crispness to the air. This month sees approximately 122 mm (4.8 in) of precipitation, spread over 16 days, creating a lush and vibrant landscape but also prompting visitors to be prepared for rain. The humidity hovers around 83%, enhancing the refreshing mountain atmosphere and offering a unique experience for those exploring this picturesque alpine village.

September Temperature in Grindelwald

In September, Grindelwald begins to transition from the warmth of summer to the chill of autumn. With temperatures ranging from a minimum of -8°C (17°F) to a maximum of 18°C (65°F), the average hovers around 6°C (44°F), marking a notable drop from the peak summer months. This cooling trend signals the impending change in seasons, offering a crispness in the air that is invigorating for outdoor enthusiasts. As the stunning landscapes begin to take on fall colors, visitors can enjoy mild days and cool evenings, making September a delightful time to explore this picturesque Swiss village before winter's chill sets in.

September Weather in Grindelwald: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Grindelwald, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Grindelwald, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec141923303748515044352517
Data source: Temperature data for Grindelwald generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Grindelwald

In September, Grindelwald experiences a transition into autumn, marked by a precipitation total of 122 mm (4.8 in) over 16 days. This amount is notably lower than the summer's peak rainfall in July and August, yet it remains consistent with the more moderate wetness seen in the spring months. While the precipitation tends to diminish as the region prepares for the colder months ahead, September still brings enough rain to keep the landscape lush and vibrant. This month serves as a gentle reminder of nature's rhythms, balancing between the lushness of summer and the forthcoming crispness of fall, making Grindelwald a picturesque destination throughout the season.

September Precipitation Trends in Grindelwald

The chart displays monthly precipitation patterns in Grindelwald, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Grindelwald, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec168114147102165168197195122181118229
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Grindelwald

In Grindelwald, Switzerland, September sees a humidity level of 83%, which is slightly above the summer average and reflects a transition towards the wetter months ahead. As the year progresses, humidity levels gradually decrease from a peak of 92% in January, showcasing a pattern of fluctuating moisture throughout the seasons. Notably, the summer months maintain relatively low humidity, with August dipping to 80%. However, September marks a subtle increase, hinting at the onset of the autumn season where conditions start to dampen once again. This gentle rise in moisture leads into the heavier humidity experienced in the subsequent fall months, where October and December both soar back to 90%. Thus, September stands as a bridge from the drier summer, embracing the cool, crisp air of fall while preparing for the wet winter ahead.

September Average Humidity in Grindelwald

This chart illustrates the average monthly humidity levels in Grindelwald, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Grindelwald is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec92%89%87%84%80%82%83%80%83%90%89%90%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Grindelwald

In September, Grindelwald, Switzerland experiences a UV Index of 7, categorized as high, which means a typical burn time is around 25 minutes for fair-skinned individuals. This marks a noticeable decline from the extreme levels seen during the peak summer months — June reached a staggering UV Index of 11. As summer fades, September’s more moderate sun exposure invites outdoor enthusiasts to enjoy the stunning alpine scenery, though caution is still advised. Visitors should keep the UV index in mind to ensure safe sun practices. For more detailed information, you can check the Grindelwald UV Index.

Maximum UV Index Levels in Grindelwald for September

The chart shows the monthly maximum UV Index (UVI) for Grindelwald in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Grindelwald typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec348910111097632
Data source: Grindelwald September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Grindelwald

As summer transitions into autumn, September in Grindelwald, Switzerland still basks in a generous embrace of sunshine, offering approximately 323 hours of radiant daylight. This marks a delightful tapering from the peak sunshine hours of July and August, which reached 417 and 382 hours respectively. Despite the gradual decline, September retains a luminous charm that welcomes outdoor enthusiasts and nature lovers. The month stands out as a reminder that while the longer, sun-filled days may be fading, the warmth and vibrancy of summer linger beautifully, providing ample opportunity for hiking and exploring the stunning alpine landscapes before the chill of October sets in. As the season shifts, Grindelwald continues to shine softly, inviting all to revel in its enchanting allure.

Monthly Sunshine Duration in Grindelwald: September Highlighted

The September sunshine duration represents the total number of hours Grindelwald experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec181h236h306h353h365h389h417h382h323h287h231h205h
Data source: Grindelwald September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Grindelwald During September

In September, the likelihood of sunny weather in Grindelwald, Switzerland stands at 21%, which marks a shift towards slightly brighter days as summer fades. While this percentage is notably higher than the balmy months of July and August, which linger around 23%, it still reflects the waning sunshine as autumn approaches. Interestingly, September sits just below the spring months of April and May, both offering a 36% chance of sun. As the season transitions, visitors can expect a blend of enchanting autumn colors paired with occasional sunny spells, making it a picturesque time to explore the stunning landscapes of this alpine gem.

Percentage of Sunny Days in September in Grindelwald

The chart illustrates the percentage of sunny days in Grindelwald throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Grindelwald experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec16%33%36%36%23%23%23%30%21%38%27%33%
Data source: Grindelwald September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Grindelwald in September

As summer fades in Grindelwald, Switzerland, September presents a gentle transition with 12 hours of daylight, gradually retreating from the sunlit abundance of the summer months, which peaked at 15 hours in June and July. This month signals the beginning of autumn, as the lush greenery starts to take on the warm hues of fall. With daylight decreasing from August's 14 hours, visitors can still enjoy a substantial amount of sunlight while engaging in outdoor adventures, soaking in the stunning alpine views. As the days shorten, the landscape transforms, offering a picturesque backdrop that embodies the essence of the changing seasons, setting the stage for the cozy charm of autumn ahead.

Average Daylight Hours in Grindelwald for September

The chart illustrates the variation in daylight duration in Grindelwald throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 1m10h 18m11h 56m13h 36m15h 1m15h 45m15h 22m14h 6m12h 30m10h 50m9h 22m8h 37m
Data source: Grindelwald daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Grindelwald

In Grindelwald, Switzerland, the September winds usher in a gentle shift in the seasonal weather patterns. With an average wind speed of just 1.0 m/s (2 mph), this month marks the calmest period of the year, showcasing a serene tranquility that contrasts with the breezy vibrancy of summer. Throughout the earlier months, wind speeds remained consistent around 3 mph, but as autumn approaches, a noticeable reduction reveals itself. This downward trend, which continues until a slight uptick in October, invites visitors to experience the breathtaking alpine scenery without the disruptive gusts, making September an ideal time for leisurely hikes and reflective moments amidst the stunning backdrop of the Swiss Alps. As the winds soften, they carry the promise of the crisp, invigorating air that autumn brings, enhancing the beauty of this picturesque destination.

Average September Wind Speed in Grindelwald

The chart displays monthly wind speed patterns in Grindelwald, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec1.51.41.31.31.31.21.21.21.0 m/s1.51.31.3
Data source: Grindelwald September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Grindelwald Compares to Other Months

Weather in Grindelwald varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Grindelwald, focusing on differences in temperature, rainfall, humidity, and UV levels.

In September, temperatures in Grindelwald typically range from a chilly minimum of -8°C (17°F) to a comfortable maximum of 18°C (65°F), averaging around 6°C (44°F). The month sees considerable precipitation, with 122 mm (4.8 in) falling over 16 days and humidity levels at 83%. In contrast, January brings harsher conditions, characterized by much lower temperatures, with minimums reaching -24°C (-11°F) and a maximum of only 5°C (41°F), resulting in an average of -10°C (15°F). Precipitation increases slightly to 168 mm (6.6 in), falling over 13 days, along with a higher humidity level of 92%. For more details on January weather, you can refer to Grindelwald weather in January.

September and February present stark contrasts in weather conditions. September typically experiences milder temperatures, ranging from a minimum of -8°C (17°F) to a maximum of 18°C (65°F), with an average temperature of 6°C (44°F). Precipitation is relatively moderate, with 122 mm (4.8 in) falling over about 16 days, and humidity levels hover around 83%.

In contrast, February is much colder, featuring a minimum temperature of -25°C (-12°F) and a maximum of only 7°C (45°F), with an average temperature of -7°C (20°F). Although precipitation is slightly lower at 114 mm (4.5 in) over 12 days, the humidity is higher at 89%, creating a distinctly different atmosphere. For those interested in more details about February weather, check out Grindelwald weather in February.

Comparing the weather in September and March reveals notable differences in temperature and precipitation. September experiences milder conditions, with an average temperature of 6°C (44°F) ranging from a minimum of -8°C (17°F) to a maximum of 18°C (65°F). In contrast, March is significantly colder, with an average temperature of -5°C (24°F) and temperatures dropping as low as -26°C (-15°F). While both months see precipitation on about 16 days, March averages slightly more at 147 mm (5.8 in) compared to September's 122 mm (4.8 in). Humidity levels are also higher in March at 87%, compared to September's 83%. For a more detailed look at weather conditions during March, check out Grindelwald weather in March.

In comparing the weather of September and April, we see notable differences in temperature and conditions. September typically presents a milder climate with average temperatures ranging from -8°C (17°F) at night to a pleasant high of 18°C (65°F) during the day, coupled with a significant amount of rainfall—122 mm (4.8 in) over 16 days and an average humidity of 83%. In contrast, April experiences colder temperatures, with minimums dropping to -17°C (1°F) and a daytime maximum of 11°C (53°F), along with slightly lower precipitation levels of 102 mm (4.0 in) across 13 days and a similar humidity at 84%. For a more detailed look at April weather, you can check this link: Grindelwald weather in April.

When comparing the weather in September and May, we see some notable differences. September tends to be milder, with average temperatures reaching up to 6°C (44°F) and a maximum of 18°C (65°F), while May has slightly cooler averages, peaking at 16°C (62°F) with an average of 3°C (37°F). Additionally, September experiences around 122 mm (4.8 in) of precipitation over 16 days, which is less than May's 165 mm (6.5 in) spread over 21 days. Despite these variations, both months have high humidity levels, with September at 83% and May slightly lower at 80%. For a closer look at May's weather specifics, you can check Grindelwald weather in May.

When comparing the weather in September and June, several distinct differences emerge. September typically experiences cooler temperatures, ranging from a minimum of -8°C (17°F) to a maximum of 18°C (65°F), with an average of 6°C (44°F). In contrast, June boasts milder temperatures, with a minimum of -4°C (25°F) and a maximum that can reach 25°C (77°F), averaging 9°C (48°F). Additionally, June tends to be wetter, receiving about 168 mm (6.6 in) of precipitation over 20 days, compared to September's 122 mm (4.8 in) across 16 days. Humidity levels are quite similar in both months, hovering around 82% in June and 83% in September. For those interested in more detailed information, you can check Grindelwald weather in June.

In comparing the weather of September and July, it is clear that July is typically warmer, with average temperatures ranging from a minimum of 0°C (32°F) to a maximum of 24°C (75°F), while September experiences cooler temperatures, with a range from -8°C (17°F) to 18°C (65°F). July also sees more substantial rainfall, totaling 197 mm (7.8 in) over an average of 24 days, compared to September's 122 mm (4.8 in) spread over 16 days. Despite both months having a humidity level of 83%, the overall climate of July is generally more pleasant and suitable for outdoor activities, making it a favored time for visitors. For more details, you can view the full weather patterns for the month by clicking Grindelwald weather in July.

September weather in Grindelwald tends to be cooler than in August, with average temperatures dipping from around 10°C (50°F) in August to just 6°C (44°F) in September. While both months experience notable precipitation, September has a lower total of 122 mm (4.8 in) compared to August's 195 mm (7.7 in), though it still rains on a significant number of days in both months—16 days in September versus 21 days in August. Humidity levels are quite similar, with September slightly higher at 83% compared to August's 80%. For more detailed insights into August weather, check out Grindelwald weather in August.

In September, temperatures range from a minimum of -8°C (17°F) to a maximum of 18°C (65°F), with an average of 6°C (44°F). The month sees significant rainfall, totaling 122 mm (4.8 in) over 16 days, while humidity remains relatively high at 83%. In contrast, October brings cooler temperatures, with a minimum of -11°C (12°F) and a maximum of 14°C (57°F), resulting in an average of 2°C (35°F). Precipitation increases to 181 mm (7.1 in) across 13 days, and humidity rises to 90%. For more details on the weather specifics, check out Grindelwald weather in October.

September and November present a stark contrast in weather conditions. In September, temperatures range from a minimum of -8°C (17°F) to a maximum of 18°C (65°F), with an average of 6°C (44°F). This month experiences substantial precipitation, totaling 122 mm (4.8 in) over 16 days, along with a humidity level of 83%. In contrast, November sees a significant drop in temperatures, with a minimum of -21°C (-5°F) and a maximum of 10°C (50°F), leading to an average of -4°C (25°F). Precipitation remains similar at 117 mm (4.6 in), but occurs over just 15 days, and the humidity increases slightly to 88%. For a detailed look at weather patterns, check out Grindelwald weather in November.

In September, weather in Grindelwald is generally milder, with temperatures ranging from a minimum of -8°C (17°F) to a maximum of 18°C (65°F) and an average of 6°C (44°F). The month experiences about 122 mm (4.8 in) of precipitation over 16 days, with humidity levels around 83%. In contrast, December brings much colder conditions, with temperatures dropping to a minimum of -24°C (-11°F) and an average of -8°C (18°F), peaking at only 4°C (39°F). Additionally, December is wetter, with 229 mm (9.0 in) of precipitation spread over 19 days and humidity rising to 90%. For more details on December weather, check out Grindelwald weather in December.

Compare Grindelwald's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Grindelwald

In September, Grindelwald experiences a unique transition from the warmth of summer to the chill of autumn, with mild temperatures that provide a refreshing escape compared to the peak summer months. While the mountains begin to take on their stunning fall hues, visitors should be prepared for increased humidity and frequent rainfall, as the region sees more precipitation than in the drier summer. This variance in weather can lead to dramatic shifts, making it essential for adventurers to plan accordingly. For a deeper dive into the climate intricacies of this beautiful destination, check out Grindelwald Climate.