September Weather in Brig, Switzerland

Last updated: August 27, 2025

In September, the picturesque town of Brig, Switzerland experiences a delightful transition into autumn, showcasing a maximum temperature of 21°C (69°F) and dropping to an average of 8°C (48°F). With a minimum temperature reaching as low as -4°C (25°F), the month brings a crispness to the air. Rainfall is notably frequent, accumulating to 116 mm (4.6 in) over 16 days, resulting in a relative humidity of 83% that accentuates the refreshing atmosphere. This combination of cool temperatures and moderate precipitation creates a unique charm, inviting visitors to experience the breathtaking autumn landscape of the Swiss Alps.

September Temperature in Brig

In September, Brig, Switzerland begins to transition from the warmth of summer to the crispness of autumn. Temperatures range from a minimum of -4°C (25°F) to a comfortable maximum of 21°C (69°F), signifying the last remnants of warm days before winter sets in. The average temperature sits around 8°C (48°F), providing a refreshing chill in the air, ideal for outdoor activities against a backdrop of stunning fall foliage. As the month progresses, the nights grow cooler, hinting at the winter chill that follows, while the pleasant daytime warmth invites residents and visitors alike to enjoy the scenic beauty of this Alpine town. This gradual shift underscores September as a month of change, embracing both the warmth of summer and the cool embrace of autumn.

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

The chart illustrates September temperature patterns in Brig, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Brig, 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).
JanFebMarAprMayJunJulAugSepOctNovDec162227344152555447392718
Data source: Temperature data for Brig 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 Brig

In September, Brig experiences a notable shift in its precipitation patterns, recording 116 mm (4.6 in) of rain over 16 days. This amount is a slight decrease compared to the heavier rains of the summer months, with August having seen 151 mm over 18 days. As the region transitions into autumn, the frequency of rainy days tends to stabilize, reflecting a more balanced distribution of moisture. This trend hints at the onset of cooler temperatures, paving the way for the wetter months that follow. Interestingly, September's precipitation is somewhat consistent with the overall trend of increased rain in the early autumn months, helping to nurture the lush landscapes that characterize Brig.

September Precipitation Trends in Brig

The chart displays monthly precipitation patterns in Brig, 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 Brig, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec11575111113163173131152116195141156
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Brig

In Brig, Switzerland, September brings a moderate humidity level of 83%, marking a slight increase compared to the prior months, particularly August's 80%. This subtle uptick suggests a gradual transition into the wetter autumn months, as the air begins to retain more moisture in preparation for the colder seasons ahead. Overall, the trend from late summer into early autumn shows relatively stable humidity levels, fluctuating between 80% and 84% until October, when humidity rises again to 90%. The upcoming months promise a significant shift, where residents and visitors can expect a distinctly more humid atmosphere, characteristic of the Swiss autumn.

September Average Humidity in Brig

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

In September, Brig experiences a UV Index of 7, which falls into the high exposure category. With a recommended burn time of just 25 minutes, this month marks a slight decrease from the intense levels seen in the summer, yet it still requires attention to sun safety. Following the extreme peaks of June's 11 and July's 10, the UV Index in September signifies a transition towards milder autumn conditions while reminding residents and visitors to remain cautious. It’s a time when outdoor activities can still be enjoyed, but awareness of sun exposure is crucial. For more detailed insights, you can check the Brig UV Index.

Maximum UV Index Levels in Brig for September

The chart shows the monthly maximum UV Index (UVI) for Brig 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 Brig typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec348910111097632
Data source: Brig 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 Brig

As summer gently transitions into autumn, September in Brig, Switzerland continues to bask in a generous amount of sunshine, with 323 hours of brilliant daylight—just slightly dimmer than the sun-soaked days of July and August. This month showcases a stunning peak in sunlight that reflects the vibrant colors of the surrounding landscape, inviting outdoor enthusiasts and nature lovers to embrace the last warm days before the chill of October sets in. With a gradual decline in sunlight hours as the year progresses, September serves as a beautiful reminder of the lingering warmth of summer, balancing the onset of fall with its comforting glow.

Monthly Sunshine Duration in Brig: September Highlighted

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

Chance of Sun in Brig During September

In Brig, Switzerland, September presents a moderate chance of sunny weather, with a likelihood of 23%. This marks a noticeable dip from the sunny disposition seen in August, which boasts a 40% chance of sunshine, reflective of the transition from summer to autumn. Notably, summer months like June and July also exhibit lower sunshine probabilities compared to the peak of spring. This trend suggests that while September can still offer pleasant days, it’s prudent for visitors to prepare for variability as the season shifts, embracing the crisp air and the charming landscape that heralds autumn in the Alps.

Percentage of Sunny Days in September in Brig

The chart illustrates the percentage of sunny days in Brig 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 Brig experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec19%36%43%40%31%22%31%40%23%37%28%38%
Data source: Brig September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Brig in September

As September unfolds in Brig, Switzerland, the days start to shorten, offering about 12 hours of daylight—a gentle transition from the summer's long, radiant days. This decline follows the peak of 15 hours in both June and July, signaling the approach of autumn. The gradual decrease in sunlight not only marks a shift in the season but also invites a cozy atmosphere, perfect for enjoying the stunning landscapes as the leaves begin to change. After basking in 14 hours of daylight in August, September’s sun offers a softer, yet still charming, daylight experience, bridging the gap between summer's vibrancy and the calm of winter.

Average Daylight Hours in Brig for September

The chart illustrates the variation in daylight duration in Brig throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 3m10h 19m11h 56m13h 35m14h 59m15h 43m15h 20m14h 4m12h 29m10h 51m9h 24m8h 39m
Data source: Brig daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Brig

As September unfurls in Brig, Switzerland, the gentle breeze captures the essence of early autumn, with average wind speeds dipping to 0.9 m/s (2 mph). This marks the lowest point of the year, a transition from the more robust winds of spring and summer. With each passing month, the wind's presence steadily wanes, suggesting a tranquil shift in the landscape. From January through August, the breeze remains relatively mild, but September whispers a soft farewell to summer's warmth, hinting at the fresh gusts that October will soon bring. This subtle reduction in wind speed encourages a serene moment for reflection amidst the stunning alpine backdrop, inviting locals and visitors alike to savor the beauty of Brig in its mellow fall glow.

Average September Wind Speed in Brig

The chart displays monthly wind speed patterns in Brig, 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.
JanFebMarAprMayJunJulAugSepOctNovDec1.51.21.21.21.31.11.11.10.9 m/s1.31.21.4
Data source: Brig September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Brig Compares to Other Months

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

September and January present starkly contrasting weather conditions. In September, temperatures range from a chilly minimum of -4°C (25°F) to a pleasant maximum of 21°C (69°F), with an average temperature of 8°C (48°F). This month experiences substantial rainfall, totaling 116 mm (4.6 in) over about 16 days, and humidity levels around 83%. Conversely, January is much colder, with temperatures plummeting to a minimum of -25°C (-13°F) and averaging -9°C (16°F), peaking at a mere 4°C (40°F). Rainfall is slightly lower at 115 mm (4.5 in), occurring over just 10 days, but humidity rises to 92%, contributing to the crisp, frigid air. For more details on January weather, visit Brig weather in January.

September and February present markedly different weather patterns, with September being milder and more temperate. In September, temperatures range from a minimum of -4°C (25°F) to a pleasant maximum of 21°C (69°F), averaging around 8°C (48°F). The month experiences significant precipitation at 116 mm (4.6 in) over about 16 days, contributing to a humidity level of 83%. In contrast, February brings much colder conditions, with temperatures dipping to a minimum of -23°C (-9°F) and peaking at only 10°C (50°F), resulting in an average of -5°C (23°F). Precipitation is less in February at 75 mm (2.9 in), occurring over 12 days, yet the humidity rises slightly to 89%. For a deeper view of the weather specifics during this chilly month, visit Brig weather in February.

The weather in September is notably milder than in March, with average temperatures ranging from a chilly 8°C (48°F) to a comfortable high of 21°C (69°F). In contrast, March is significantly colder, featuring average temperatures that hover around -3°C (27°F), with nighttime lows plummeting to -24°C (-11°F). Despite the slight difference in total precipitation, with September receiving 116 mm (4.6 in) and March 111 mm (4.4 in), both months share the same number of wet days at 16. Additionally, March tends to have a slightly higher humidity level at 87% compared to September's 83%. For more details, you can refer to Brig weather in March.

September and April showcase contrasting weather patterns, reflecting the transition from summer to autumn and winter to spring, respectively. In September, temperatures range from a minimum of -4°C (25°F) to an average of 8°C (48°F), peaking at a pleasant 21°C (69°F). This month sees moderate humidity at 83% and experiences 116 mm (4.6 in) of precipitation over 16 days. In comparison, April features cooler temperatures, with a minimum of -15°C (5°F) and an average of just 1°C (35°F), reaching a maximum of 14°C (58°F). Although April is only slightly drier, with 113 mm (4.4 in) of precipitation over 12 days, the humidity remains relatively high at 84%. For more details on the weather during this month, you can check Brig weather in April.

September and May present contrasting weather patterns, showcasing the transition from summer to autumn. In September, temperatures range from a minimum of -4°C (25°F) to a maximum of 21°C (69°F), with an average of 8°C (48°F) and a relatively humid environment at 83%. The month experiences about 116 mm (4.6 in) of precipitation over 16 days, marking a gradual increase in rainfall as the season changes.

In comparison, May is slightly cooler with temperatures ranging from -11°C (12°F) to 19°C (67°F), and an average temperature of 5°C (41°F). This month sees higher precipitation levels at 163 mm (6.4 in) over 21 days, although the humidity is slightly lower at 80%. The wetter and cooler conditions in May lead to a more damp environment, making it feel quite different from the milder September weather. For more details on the weather in May, check out Brig weather in May.

When comparing the weather in June and September, notable differences emerge in temperature and precipitation patterns. June experiences a warmer temperature range, with average highs reaching 26°C (80°F) compared to September's maximum of 21°C (69°F). Conversely, September boasts a slightly lower minimum temperature of -4°C (25°F) compared to June's -2°C (28°F). Additionally, June sees higher precipitation levels, accumulating 173 mm (6.8 in) over 19 days, while September records 116 mm (4.6 in) across 16 days. Both months maintain a similar humidity level, hovering around 82-83%. For more specific details regarding June weather in Brig, you can refer to Brig weather in June.

In comparing the weather of September and July, it is evident that July tends to be warmer, with average temperatures reaching 13°C (55°F) compared to September's cooler average of 8°C (48°F). The maximum temperature in July can reach up to 24°C (75°F), while September peaks at 21°C (69°F). Both months experience high humidity levels of 83%, but July records slightly more precipitation at 131 mm (5.2 in) over 19 days, whereas September has 116 mm (4.6 in) over 16 days. For more detailed insights into July's weather, you can check Brig weather in July.

September weather is generally cooler than in August, with average temperatures dropping from 12°C (54°F) to 8°C (48°F). The minimum temperature in September reaches a low of -4°C (25°F), while in August, it is a milder 1°C (35°F). Precipitation in September, totaling 116 mm (4.6 in), occurs over 16 days, compared to August's higher 151 mm (6.0 in) over 18 days. Humidity rates are slightly elevated in September at 83%, compared to August's 80%. For more details about August's weather, you can visit Brig weather in August.

September weather in Brig is characterized by relatively mild temperatures, with a minimum of -4°C (25°F) and an average of 8°C (48°F), peaking at a maximum of 21°C (69°F). However, it also sees considerable precipitation, accumulating 116 mm (4.6 in) over 16 days, accompanied by a humidity level of 83%. In contrast, October brings a significant drop in average temperatures, averaging 4°C (39°F) with lows reaching -8°C (19°F) and highs of only 15°C (60°F). Additionally, October experiences even higher precipitation at 195 mm (7.7 in) over 13 days, along with increased humidity at 90%. For a detailed look at the conditions in October, visit Brig weather in October.

In September, the weather in Brig is characterized by milder temperatures, with daily averages reaching around 8°C (48°F) and maximums of 21°C (69°F). Rainfall is moderate, with about 116 mm (4.6 in) over 16 days, and humidity levels sit comfortably at 83%. In contrast, November brings a significant drop in temperatures, with average conditions hovering around -3°C (27°F) and maximums of only 12°C (54°F). The month is wetter, with precipitation increasing to 141 mm (5.5 in) across the same number of days, and humidity rises slightly to 88%. For a more detailed look at this month's climate, check out Brig weather in November.

September and December exhibit stark contrasts in weather conditions. In September, temperatures range from a minimum of -4°C (25°F) to a maximum of 21°C (69°F), with an average of 8°C (48°F). The month experiences 116 mm (4.6 in) of precipitation across 16 days, accompanied by a humidity level of 83%. In contrast, December is significantly colder, with temperatures plummeting to a minimum of -25°C (-12°F) and only reaching a maximum of 4°C (40°F), averaging -8°C (18°F). This month sees increased precipitation at 156 mm (6.2 in) over 17 days, and humidity rises to 90%. For more details on December weather in Brig, you can refer to Brig weather in December.

Compare Brig's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Brig

As September unfolds in Brig, it marks a notable shift in the weather compared to the sunnier months of summer. With average temperatures dipping to a cooler 8°C, the month introduces a refreshing crispness to the air, while the maximum daytime highs still flirt with pleasant warmth. However, the increase in precipitation, with rain gracing about half the days of the month, adds a layer of unpredictability, making it a transitional period toward the wetter autumn season. Humidity levels rise, enveloping the region in a somewhat damp embrace that can change the appeal of outdoor activities. For those keen on exploring Brig’s vibrant landscapes, understanding these seasonal changes is essential. For a deeper dive into the weather patterns, check out Brig Climate.