September Weather in Braine-l'Alleud, Belgium

Last updated: August 21, 2025

September in Braine-l'Alleud, Belgium showcases a unique blend of summer warmth and early autumn chill. With maximum temperatures soaring to 33°C (91°F), the month still holds onto the lingering summer vibes. The average temperature settles at a comfortable 15°C (60°F), while cool evenings can dip as low as 4°C (39°F). Rainfall makes its presence felt with 55 mm (2.2 in) spread over 9 days, contributing to an overall humidity level of 82%. This seasonal transition invites both sunny days and occasional showers, creating a picturesque backdrop for outdoor activities and a reminder of nature’s ever-changing rhythms.

September Temperature in Braine-l'Alleud

In September, Braine-l'Alleud transitions into a milder climate, offering a refreshing reprieve from the summer heat. The temperatures begin with a minimum of 4°C (39°F), climbing to a comfortable average of 15°C (60°F), and peaking at a pleasant maximum of 33°C (91°F). This month showcases a noticeable drop compared to the blazing highs of late summer, yet it still retains warmth, making it an ideal time to enjoy outdoor activities. As autumn approaches, the cooling trend hints at the seasonal shift ahead, with temperatures gradually falling in the following months. The gentle warmth of September provides a perfect backdrop for experiencing the vibrant landscapes of the area before the chill of October sets in.

September Weather in Braine-l'Alleud: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Braine-l'Alleud, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Braine-l'Alleud, 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).
JanFebMarAprMayJunJulAugSepOctNovDec394245505664666660544542
Data source: Temperature data for Braine-l'Alleud 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 Braine-l'Alleud

In September, Braine-l'Alleud experiences a moderate drop in precipitation, receiving 55 mm (2.2 inches) of rainfall over 9 days. This marks a shift from the previous month, August, which was notably wetter with 80 mm (3.2 inches) across 14 days. Despite the decrease, September's rainfall contributes to the region's lush greenery, as it falls before the milder, drier months of fall. Over the year, September aligns closely with the spring and early summer months in terms of precipitation levels, showcasing a trend toward balanced weather patterns as the region transitions into autumn. While it's less rainy than the peak summer months, the steady rain in September plays a vital role in maintaining the area's vibrant landscape.

September Precipitation Trends in Braine-l'Alleud

The chart displays monthly precipitation patterns in Braine-l'Alleud, 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 Braine-l'Alleud, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec656971375866718055765793
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Braine-l'Alleud

September in Braine-l'Alleud, Belgium, ushers in a subtle shift in humidity, settling at 82%. This marks a slight increase from the summer lull of 76% in August, hinting at the approaching embrace of autumn. As the year progresses, humidity levels consistently rise in the fall, climbing back to 89% by October and peaking at 92% in the winter months of November and December. Such trends reflect a transition from the drier summer climate into the wetter conditions of the colder months, capturing the essence of Belgium's shifting seasons.

September Average Humidity in Braine-l'Alleud

This chart illustrates the average monthly humidity levels in Braine-l'Alleud, 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 Braine-l'Alleud is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec91%89%87%85%82%82%80%76%82%89%92%92%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Braine-l'Alleud

As summer fades into September in Braine-l'Alleud, Belgium, the UV Index reflects a shift towards more moderate sun exposure. With a UV Index of 5 this month, the exposure category is classified as moderate, allowing for a burn time of approximately 30 minutes in direct sunlight. This trend shows a decline from the higher indices of 7 and 8 experienced in the previous months of July and August, where sun safety measures were more critical. As autumn approaches, it's essential to adjust your sun protection habits accordingly. For more detailed information on UV levels throughout the year, visit the Braine-l'Alleud UV Index.

Maximum UV Index Levels in Braine-l'Alleud for September

The chart shows the monthly maximum UV Index (UVI) for Braine-l'Alleud 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 Braine-l'Alleud typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec124578875421
Data source: Braine-l'Alleud 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 Braine-l'Alleud

September in Braine-l'Alleud heralds the gentle transition from the vibrant summer months into the crisp embrace of autumn. With 319 hours of sunshine, it stands out as a month filled with golden light, though less radiant than the sun-drenched peak of July, which boasts 406 hours. This early autumn month still offers a significant amount of daylight, allowing residents and visitors alike to savor the fading warmth before the days grow shorter. The gradual decline from August’s 379 hours hints at the changing season, yet September maintains a cozy glow, inviting outdoor activities and leisurely strolls amidst the colorful foliage that begins to appear. As the sun's presence wanes in the following months, September serves as a reminder of summer's lingering charm.

Monthly Sunshine Duration in Braine-l'Alleud: September Highlighted

The September sunshine duration represents the total number of hours Braine-l'Alleud 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.
JanFebMarAprMayJunJulAugSepOctNovDec121h200h266h346h394h398h406h379h319h240h190h143h
Data source: Braine-l'Alleud September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Braine-l'Alleud During September

In Braine-l'Alleud, Belgium, September brings a moderate 36% chance of sunny weather, marking a slight uptick in sunshine compared to the summer months. While July and August bask in around 34% and 29% sunny days respectively, September's figures reflect a seasonal transition that leads into autumn. This increase is noteworthy as the likelihood of sunshine begins to decline again in October, dropping to 32%. As summer fades, you can expect a blend of warmth and cloud, making September a delightful period for those hoping to catch a few rays before the colder months set in.

Percentage of Sunny Days in September in Braine-l'Alleud

The chart illustrates the percentage of sunny days in Braine-l'Alleud 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 Braine-l'Alleud experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec11%30%40%50%33%34%34%29%36%32%24%16%
Data source: Braine-l'Alleud September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Braine-l'Alleud in September

As summer recedes, September in Braine-l'Alleud, Belgium, marks a transitional period in daylight duration. With approximately 12 hours of daylight, the month showcases a gentle decline from the bright and lengthy days of summer. The gradual shift is evident as the days became shorter than the vibrant 14 hours of August, signaling the approach of autumn. This reduction, while still providing ample light for outdoor activities and harvests, hints at the impending seasonal change. Following September, daylight continues its descent, dropping to 10 hours in October, reflecting a well-known trend of diminishing sunlight as the year progresses toward the winter months.

Average Daylight Hours in Braine-l'Alleud for September

The chart illustrates the variation in daylight duration in Braine-l'Alleud throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 31m10h 2m11h 55m13h 50m15h 31m16h 23m15h 55m14h 25m12h 34m10h 39m8h 56m8h 2m
Data source: Braine-l'Alleud daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Braine-l'Alleud

As September arrives in Braine-l'Alleud, Belgium, the wind begins to gently whisper a transition into autumn, averaging a mild 3.0 m/s (7 mph). This marks a noticeable dip from the summer months, where winds were slightly stronger, peaking at 4.4 m/s (10 mph) in May. The pattern of wind speed reveals a gradual cooling trend that characterizes the late months of the year, with figures generally climbing again into October. Interestingly, while the summer's breezes linger, September stands out with its more tranquil air, inviting a sense of calm before the brisker winds that will follow. As the leaves begin to turn, this softening of the wind serves as a reminder of the sweet, fleeting moments of late summer.

Average September Wind Speed in Braine-l'Alleud

The chart displays monthly wind speed patterns in Braine-l'Alleud, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.44.64.03.44.42.83.33.43.0 m/s4.33.34.2
Data source: Braine-l'Alleud September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Braine-l'Alleud Compares to Other Months

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

September and January present stark contrasts in weather. In September, temperatures range from a mild 15°C (60°F) on average, with maximums reaching up to 33°C (91°F), making it a warm transition from summer. The month sees about 55 mm (2.2 in) of precipitation over roughly nine days, and humidity levels sit at a comfortable 82%. In contrast, January experiences much colder weather, with average temperatures dropping to around 4°C (39°F) and maximums peaking at 14°C (57°F). The chilly month receives slightly more precipitation, totaling 65 mm (2.5 in) over about 12 days, accompanied by higher humidity of 91%. For a detailed look at January weather, visit Braine-l'Alleud weather in January.

In comparing the weather between September and February, September is generally milder with temperatures ranging from a minimum of 4°C (39°F) to a maximum of 33°C (91°F), averaging around 15°C (60°F). The month sees 55 mm (2.2 in) of precipitation over about 9 days, accompanied by a humidity level of 82%. In contrast, February experiences much colder conditions, with temperatures plummeting as low as -8°C (17°F) and peaking at 19°C (66°F), averaging around 5°C (42°F). Precipitation increases slightly to 69 mm (2.7 in) over 12 days, with a higher humidity of 89%. For more detailed insights about February weather in the area, you can check Braine-l'Alleud weather in February.

September and March present contrasting weather conditions in terms of temperature and precipitation. In September, temperatures range from a mild minimum of 4°C (39°F) to a warm maximum of 33°C (91°F), with an average of 15°C (60°F). The month experiences about 55 mm (2.2 in) of precipitation over 9 days, accompanied by a humidity level of 82%. In contrast, March brings cooler temperatures, ranging from a minimum of -8°C (17°F) to a maximum of 23°C (74°F) and an average of 7°C (45°F). It is wetter with 70 mm (2.8 in) of precipitation spread over 14 days, alongside a slightly higher humidity level of 87%. For more details, check out Braine-l'Alleud weather in March.

When comparing the weather in September and April, several notable differences emerge. September tends to be warmer, with average temperatures reaching around 15°C (60°F) and maximums peaking at 33°C (91°F), while April's average hovers at a cooler 10°C (50°F), with a maximum of 27°C (80°F). In terms of precipitation, September receives about 55 mm (2.2 in) across approximately 9 days, whereas April is slightly drier, with 37 mm (1.5 in) of rain over about 8 days. Additionally, both months experience high humidity, but September is slightly lower at 82%, compared to April’s 85%. For more detailed information, check out Braine-l'Alleud weather in April.

September and May present similar weather patterns in terms of humidity, both hovering around 82%. However, September tends to have slightly warmer temperatures, with an average of 15°C (60°F) compared to May's 13°C (57°F). The maximum temperatures in both months are comparable, reaching up to 33°C (91°F) in September and 31°C (88°F) in May. Precipitation is also quite similar, with 55 mm (2.2 in) in September and 58 mm (2.3 in) in May, although May experiences a few more rainy days at 12 compared to September's 9 days. For a closer look at May weather specifics, check out Braine-l'Alleud weather in May.

When comparing the weather in September and June, both months exhibit similar maximum temperatures, reaching up to 33°C (91°F) in September and 32°C (91°F) in June. However, September generally experiences a broader temperature range, with a minimum of 4°C (39°F), compared to June's 7°C (44°F). Precipitation levels are slightly higher in June, totaling 66 mm (2.6 in) with rain occurring on 9 days, whereas September sees 55 mm (2.2 in) over the same number of days. Both months share a humidity level of 82%, giving them a similarly muggy feel. For more detailed information, you can check out Braine-l'Alleud weather in June.

When comparing the weather in September to that in July, we notice several key differences. September experiences a wider range of temperatures, with a minimum of 4°C (39°F) and a maximum of 33°C (91°F), while July has a more consistent temperature range with a minimum of 8°C (46°F) and a maximum of 39°C (102°F). Although September is slightly cooler on average at 15°C (60°F) compared to July’s 19°C (66°F), it also has lower precipitation levels, with 55 mm (2.2 in) over 9 days, in contrast to July's 71 mm (2.8 in) over 11 days. Moreover, September's humidity is slightly higher at 82% compared to July's 80%. For a more detailed look at the July weather, you can visit Braine-l'Alleud weather in July.

When comparing the weather of September to that of August, notable differences emerge. September's temperatures range from a minimum of 4°C (39°F) to a maximum of 33°C (91°F), with a comfortable average of 15°C (60°F). In contrast, August experiences higher temperatures, with a minimum of 8°C (46°F) and a maximum reaching 36°C (97°F), averaging 19°C (66°F). Additionally, September sees slightly less precipitation at 55 mm (2.2 in) over 9 days, compared to August's 80 mm (3.2 in) spread across 14 days. Humidity levels are also higher in September at 82%, while August maintains a relatively lower humidity of 76%. For a more detailed look at August weather, you can visit Braine-l'Alleud weather in August.

September and October present a notable transition in weather conditions. September boasts a wider temperature range, with minimums of 4°C and maximums reaching 33°C, resulting in an average of 15°C. In contrast, October experiences cooler temperatures, with a minimum of 1°C and a maximum of 25°C, leading to a lower average of 12°C. Precipitation increases in October, totaling 76 mm over 13 days compared to September's 55 mm over 9 days, coupled with a rise in humidity to 89%, slightly higher than September's 82%. For more detailed information, you can check Braine-l'Alleud weather in October.

September typically enjoys warmer temperatures, with averages around 15°C (60°F) and a maximum of 33°C (91°F), while November sees a significant drop, averaging 7°C (45°F), with highs reaching only 18°C (65°F). Precipitation levels are fairly similar, with September receiving 55 mm (2.2 in) across 9 days, compared to November's 57 mm (2.2 in) over 11 days. Additionally, humidity tends to be higher in November at 92%, compared to September's 82%, contributing to a notably cooler and more damp atmosphere. For more details on the weather in November, you can check out Braine-l'Alleud weather in November.

September and December present distinct contrasts in weather patterns. September features a wide temperature range, with lows around 4°C (39°F) and highs reaching up to 33°C (91°F), resulting in a pleasant average of 15°C (60°F). The month experiences about 55 mm (2.2 in) of precipitation spread over 9 days, accompanied by relatively high humidity at 82%. In contrast, December brings a chillier climate, with temperatures dipping to a minimum of -5°C (24°F) and reaching a maximum of 15°C (59°F), averaging just 5°C (42°F). The precipitation increases to 93 mm (3.7 in) over 17 days, along with higher humidity at 92%. For more details, you can check Braine-l'Alleud weather in December.

Compare Braine-l'Alleud's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Braine-l'Alleud

As summer gives way to autumn, September in Braine-l'Alleud presents a delightful transition marked by milder temperatures and an increase in humidity. Unlike the sizzling highs of July and August, September experiences a comfortable average that invites outdoor activities, although the occasional rainfall—spreading over about nine days—might remind you that fall is approaching. With average temperatures hovering around 15°C (60°F) and peaks reaching up to 33°C (91°F), it’s a month that offers a refreshing change from the summer heat while still holding onto the warmth of the season. Don't forget to explore more about the region's climate at Braine-l'Alleud Climate!