September Weather in Spiez, Switzerland

Last updated: August 27, 2025

September in Spiez, Switzerland brings a delightful mix of autumnal charm and moderate weather. With maximum temperatures reaching a pleasant 23°C (73°F) and an average of 11°C (53°F), the month invites outdoor exploration amidst stunning landscapes. However, September also showcases the region's wet side, featuring approximately 124 mm (4.9 in) of rain over about 14 days, making for lush, vibrant surroundings. Despite the rainfall, humidity levels sit at a notable 83%, creating a refreshing atmosphere perfect for those who appreciate the serene beauty of early autumn in the Swiss Alps.

September Temperature in Spiez

As September unfolds in Spiez, Switzerland, the temperatures begin to shift, marking the transition from the warmth of summer to the crispness of autumn. With minimums averaging around 0°C (32°F) and maximums reaching a pleasant 23°C (73°F), the month offers a balanced climate perfect for outdoor activities and exploration. The average temperature settles at approximately 11°C (53°F), providing a refreshing respite from the sweltering summer heat, while the days gradually shorten and the vibrant fall foliage starts to emerge. This transitional period invites visitors to embrace the scenic beauty of the region, where the cool, invigorating air complements the stunning landscapes.

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

The chart illustrates September temperature patterns in Spiez, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Spiez, 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).
JanFebMarAprMayJunJulAugSepOctNovDec263035414857605953453529
Data source: Temperature data for Spiez 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 Spiez

In September, Spiez, Switzerland experiences a notable transition towards autumn, reflected in its precipitation totals. With 124 mm (4.9 in) of rain accumulating over 14 days, the month offers a blend of wet days that keep the landscape lush and vibrant. This rainfall is slightly lower than the peak summer months of June and July, which recorded over 200 mm each, yet still maintains a steady rhythm typical of the region as it shifts from the warmth of summer. Interestingly, September marks the beginning of a gradual decline in both precipitation amounts and rainy days as the year progresses towards October, which receives marginally more rain at 138 mm (5.4 in). This pattern not only underscores the characteristic variability of Spiez's weather but also hints at the picturesque seasonal changes that entice both locals and visitors alike.

September Precipitation Trends in Spiez

The chart displays monthly precipitation patterns in Spiez, 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 Spiez, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec1231031259418222521920312413897175
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Spiez

In September, Spiez, Switzerland, experiences a humidity level of 83%, marking a slight increase from the more comfortable summer months of July and August, where humidity hovered around 80-83%. This subtle rise aligns with the annual trend of increasing humidity as the region transitions into autumn, with October bringing an even higher level of 90%. Overall, while September maintains a relatively high humidity compared to the spring months, it serves as a gentle reminder of the impending cooler, damper days ahead.

September Average Humidity in Spiez

This chart illustrates the average monthly humidity levels in Spiez, 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 Spiez 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 Spiez

As September rolls into Spiez, Switzerland, the UV Index starts to show a decline from the peak summer months, yet it remains significant at 7, categorizing it as high. This means that while the risk of harm from unprotected sun exposure is reduced compared to July and August’s extreme values, caution is still advised, with a burn time of approximately 25 minutes. Following the vibrant sunshine of summer, autumn’s arrival brings moderate UV levels in October, but September still calls for protective measures during outdoor activities. Embrace the changing season while staying sun-smart! For detailed information on UV trends throughout the year, visit Spiez UV Index.

Maximum UV Index Levels in Spiez for September

The chart shows the monthly maximum UV Index (UVI) for Spiez 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 Spiez typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec24679101097532
Data source: Spiez 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 Spiez

As summer transitions into autumn, September in Spiez, Switzerland, enjoys a delightful 322 hours of sunshine, gracefully bridging the vibrant warmth of July and August with the cooler October days. This month reflects a noticeable dip from the peak sunshine of 416 hours in July, yet it maintains a respectable brightness that outshines the earlier months of the year. Notably, the trend shows a gradual increase in sunshine hours from January's 169 hours to June's 386 hours, culminating in a radiant late-summer peak. The descent into autumn begins, but September still invites outdoor adventures and stunning views, making it a perfect time to bask in the beauty of Spiez before winter approaches.

Monthly Sunshine Duration in Spiez: September Highlighted

The September sunshine duration represents the total number of hours Spiez 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.
JanFebMarAprMayJunJulAugSepOctNovDec169h229h299h356h361h386h416h384h322h285h230h195h
Data source: Spiez September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Spiez During September

In September, the likelihood of sunny weather in Spiez, Switzerland stands at 38%, a figure that mirrors the sunniest months of August and June. As summer wanes, this chance provides a pleasant reminder of the warm days gone by. Interestingly, while the rate of sunny days rises heading into early autumn, it remains slightly lower than the peak months of April and May, which boast nearly 50% chances. This trend highlights September as a transitional month, where the lingering warmth of summer meets the crispness of approaching autumn, making it a delightful time to enjoy both sunshine and the beautiful changing scenery.

Percentage of Sunny Days in September in Spiez

The chart illustrates the percentage of sunny days in Spiez 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 Spiez experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec19%39%44%48%31%33%34%38%38%43%35%41%
Data source: Spiez September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Spiez in September

As September arrives in Spiez, Switzerland, the daylight hours begin to wane, offering a gentle transition into autumn. With approximately 12 hours of sunlight, September signals a gradual decline from the summer's peak, where 15 hours of daylight graced the longest days of June, July, and August. This slight decrease sets the stage for a cozy embrace of fall, as the day length decreases toward 10 hours in October. The trend of longer days in spring and summer gives way to shorter, more intimate evenings, inviting residents and visitors alike to relish the warm hues of early autumn while they last.

Average Daylight Hours in Spiez for September

The chart illustrates the variation in daylight duration in Spiez throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h10h 18m11h 56m13h 36m15h 2m15h 46m15h 22m14h 6m12h 30m10h 50m9h 22m8h 36m
Data source: Spiez daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Spiez

As summer whispers its farewell in September, the tranquil winds of Spiez continue to weave a soft narrative across the landscape, maintaining an average speed of 1.3 m/s (3 mph). This gentle breeze mirrors the calm that typically envelops the town during this time of year. Notably, September's wind speed aligns with the patterns of the preceding months, where fluctuations remained minimal, rarely exceeding 4 mph. As the year transitions into autumn, the consistency of these gentle winds invites both locals and visitors to embrace the serene beauty of the season, making it a perfect backdrop for leisurely strolls and quiet contemplation by Lake Thun. The soothing winds of Spiez not only enhance the picturesque vistas but also signal a collective pause before the briskness of the coming months.

Average September Wind Speed in Spiez

The chart displays monthly wind speed patterns in Spiez, 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.
JanFebMarAprMayJunJulAugSepOctNovDec1.61.71.51.51.61.31.41.31.3 m/s1.51.51.7
Data source: Spiez September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Spiez Compares to Other Months

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

September and January present contrasting weather patterns. In September, temperatures range from a chilly 0°C (32°F) to a pleasant maximum of 23°C (73°F), with an average of 11°C (53°F). The month sees about 124 mm (4.9 in) of precipitation over 14 days, accompanied by a relatively high humidity of 83%. In contrast, January offers a much colder experience, with temperatures dipping as low as -19°C (-1°F) and reaching a maximum of 9°C (48°F), resulting in an average temperature of -3°C (26°F). Precipitation remains similar at 123 mm (4.9 in) but occurs over 12 days, with humidity peaking at 92%. For a more detailed breakdown of January weather, you can visit Spiez weather in January.

September and February present a striking contrast in weather conditions. In September, temperatures range from a refreshing 0°C (32°F) at night to a comfortable maximum of 23°C (73°F) during the day, making it a pleasant transition into autumn. However, this month also sees considerable rainfall, with 124 mm (4.9 in) spread over 14 days and humidity levels averaging 83%.

In stark contrast, February experiences much colder weather, with temperatures plunging to a minimum of -18°C (-1°F) and averaging around -1°C (31°F), peaking at 14°C (58°F). Despite slightly less precipitation at 103 mm (4.0 in) over 11 days, the humidity is higher at 89%, contributing to an overall chill in the air. For more insights on February conditions, you can visit Spiez weather in February.

When comparing the weather in September and March, notable differences arise in temperature and conditions. September typically experiences milder weather with average temperatures ranging from a chilly 0°C (32°F) at night to a pleasant 23°C (73°F) during the day, while March is significantly colder, with nighttime lows dropping to -23°C (-9°F) and daytime highs peaking at 16°C (60°F). Both months see similar precipitation levels, with September receiving around 124 mm (4.9 in) over 14 rainy days and March slightly higher at 125 mm (4.9 in) across 15 days. Humidity also remains relatively high, measuring 83% in September compared to 87% in March. For a more detailed look at March conditions, you can visit Spiez weather in March.

In comparison, September generally offers milder weather with an average temperature of 11°C (53°F), while April tends to be cooler, averaging at 5°C (42°F). September experiences higher maximum temperatures, reaching up to 23°C (73°F), compared to April's peak of 19°C (67°F). Both months see significant precipitation, but September has slightly more at 124 mm (4.9 in) over 14 days, whereas April has 94 mm (3.7 in) across 12 days. Humidity levels are similar, with September at 83% and April at 84%. For more details, you can check Spiez weather in April.

September and May present contrasting weather patterns, with September experiencing milder average 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). In contrast, May starts off cooler, with temperatures dipping to a minimum of -7°C (20°F) and peaking at 25°C (78°F), yielding an average of 9°C (48°F). Both months see significant rainfall, with May receiving 182 mm (7.2 in) over 19 days of precipitation, compared to September's 124 mm (4.9 in) spread over 14 days. Interestingly, while September has a slightly higher humidity at 83%, May's humidity remains relatively high at 80%. For those looking for specific weather details, check out Spiez weather in May.

In comparing the weather between September and June, we see a notable shift in temperatures and precipitation levels. September experiences a minimum temperature of 0°C (32°F), an average of 11°C (53°F), and a maximum of 23°C (73°F), while June has slightly milder conditions with a minimum of 1°C (34°F), an average of 14°C (57°F), and a maximum of 29°C (85°F). Additionally, June tends to be wetter, with 225 mm (8.9 in) of precipitation over 18 days compared to September's 124 mm (4.9 in) over 14 days. Interestingly, both months exhibit similar humidity levels, hovering around 82-83%. For more specific details on June weather, you can visit Spiez weather in June.

In September, the weather tends to be cooler compared to July, with minimum temperatures dropping to around 0°C (32°F) and average highs reaching 23°C (73°F). In contrast, July experiences milder conditions, with minimums at 5°C (41°F) and maximums peaking at 29°C (84°F). Additionally, September has a total precipitation of 124 mm (4.9 in) over approximately 14 rainy days, while July sees more rainfall at 219 mm (8.6 in) across about 18 days. Despite similar humidity levels at 83%, the overall feel of September is noticeably fresher than the warmer, wetter July days. For more details, you can check Spiez weather in July.

In comparing the weather patterns of September and August, September tends to be cooler, 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). In contrast, August enjoys milder temperatures, featuring a minimum of 5°C (41°F) and reaching up to 28°C (82°F), with an average of 15°C (59°F). Precipitation in September is 124 mm (4.9 in) over 14 days, while August experiences higher rainfall at 203 mm (8.0 in) across 18 days. Despite the increase in precipitation during August, humidity levels are slightly lower at 80% compared to the more humid September, which has 83%. For more details about August weather in the region, you can check out Spiez weather in August.

In September, the weather features a milder temperature range with a minimum of 0°C (32°F), an average of 11°C (53°F), and a maximum of 23°C (73°F), accompanied by an average precipitation of 124 mm (4.9 in) over 14 days and a humidity level of 83%. By contrast, October brings a noticeable dip in temperatures, with minimums dropping to -4°C (26°F) and an average of 7°C (45°F), though the maximum reaches up to 19°C (67°F). Additionally, October experiences slightly higher precipitation at 138 mm (5.4 in) over 13 days, with humidity rising to 90%. For a closer look at the specific conditions in October, check out Spiez weather in October.

In September, the weather typically showcases a mild transition from summer, with temperatures ranging from a chilly 0°C at night to a comfortable 23°C during the day, accompanied by an average temperature of 11°C. The month experiences significant rainfall, with around 124 mm over about 14 days, and a humidity level of 83%.

In contrast, November marks a notable drop in temperatures, starting from a minimum of -10°C and averaging just 2°C, peaking at 18°C. Although precipitation decreases slightly to 97 mm over 13 days, the humidity rises to 88%, creating a colder and more damp atmosphere. For more insights on this month's climate, you can check Spiez weather in November.

September and December exhibit stark contrasts in weather conditions. 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) and a relatively lower precipitation total of 124 mm (4.9 in) spread over 14 days. This month also experiences a humidity level of 83%, contributing to a mild, transitional feel as summer fades.

In contrast, December brings much colder temperatures, with a minimum of -13°C (8°F) and a maximum of 9°C (49°F), averaging -2°C (29°F). Precipitation increases to 175 mm (6.9 in) over 17 days, while humidity rises to 90%, creating a damp and chilly atmosphere. For more specific insights into what to expect in Spiez during December, you can check out Spiez weather in December.

Compare Spiez's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Spiez

As September unfolds in Spiez, it brings a refreshing transition from summer's warmth to the crispness of autumn. With average temperatures dipping to a mild 11°C, the weather feels distinctly cooler compared to the peak summer months, inviting layers and cozy attire. While rainfall increases during this month, with over half the days experiencing some precipitation, it is offset by the inviting autumnal colors that start to emerge in the landscape. The increased humidity at 83% adds to the atmospheric charm, making it a unique time to enjoy the scenic beauty of Spiez. For a comprehensive overview of Spiez's climate throughout the year, visit Spiez Climate.