September Weather in Louvain-la-Neuve, Belgium

Last updated: August 21, 2025

September in Louvain-la-Neuve, Belgium, showcases a captivating blend of temperatures and weather conditions. With highs reaching 33°C (91°F), the city experiences warm spells that contrast sharply with the cooler lows of 4°C (39°F). The average temperature hovers around a pleasant 15°C (60°F), creating a comfortable atmosphere for outdoor activities. However, travelers should be prepared for the month’s 58 mm (2.3 in) of rain spread over 10 days, accompanied by humidity levels at a notable 82%. This mix invites both sun seekers and those who enjoy the serene charm of a rain-kissed landscape, making September a truly dynamic time to visit.

September Temperature in Louvain-la-Neuve

In September, Louvain-la-Neuve experiences a delightful transition into autumn, marked by a minimum temperature of 4°C (39°F) and an average of 15°C (60°F). As the month unfolds, daytime highs can soar to a warm 33°C (91°F), showcasing one of the last hurrahs of summer. This blend of mild mornings and warm afternoons creates an inviting atmosphere perfect for outdoor activities and enjoying the vibrant fall foliage that begins to appear. The noticeable dip in temperatures from the sweltering highs of July and August suggests a shift towards cooler days ahead, while still offering plenty of beautiful, sunny moments to embrace the charm of this Belgian town.

September Weather in Louvain-la-Neuve: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Louvain-la-Neuve, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Louvain-la-Neuve, 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).
JanFebMarAprMayJunJulAugSepOctNovDec394145505664666660544542
Data source: Temperature data for Louvain-la-Neuve 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 Louvain-la-Neuve

In September, Louvain-la-Neuve experiences a moderate shift in precipitation, with an average of 58 mm (2.3 in) falling over approximately 10 days. This marks a slight decrease from the wetter months of August, which topped off at 84 mm (3.3 in) during its 14 rainy days. The transition into autumn is noticeable as precipitation levels begin to taper, aligning with the changing seasons. Interestingly, September's rainfall is also lower than that recorded in nearby months, indicating a brief reprieve before the typically wetter months ahead. As the region prepares for October's anticipated jump to 78 mm (3.1 in), this September showcases the gentle ebb of summer’s rainfall, setting the stage for the impending autumnal showers.

September Precipitation Trends in Louvain-la-Neuve

The chart displays monthly precipitation patterns in Louvain-la-Neuve, 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 Louvain-la-Neuve, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec657071376072748458785892
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Louvain-la-Neuve

In September, Louvain-la-Neuve, Belgium experiences a humidity level of 82%, marking a slight increase from the drier months of summer. Following the warmest season, where humidity dipped to 76% in August, September ushers in a return to more comfortable, albeit humid, conditions reminiscent of late spring. This month acts as a transition, as humidity gradually rises again, preparing the landscape for the wetter autumn months ahead, where levels peak to 92% in November and December. With the crisp air mingling with this moderate humidity, September provides a balanced climate that many find refreshing after the summer heat.

September Average Humidity in Louvain-la-Neuve

This chart illustrates the average monthly humidity levels in Louvain-la-Neuve, 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 Louvain-la-Neuve 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 Louvain-la-Neuve

As the summer fades in Louvain-la-Neuve, September sees a notable shift in UV exposure. With a UV Index of 5, categorized as moderate, residents should be mindful of their sun exposure, as the burn time decreases to 30 minutes. This marks a transition from the higher indices of July and August, which both reached 8, indicating very high exposure levels. While September's UV Index reflects a drop from its summer peak, it remains crucial for sun safety, especially during midday hours. This month serves as a reminder that while the season cools, sun protection shouldn't be overlooked. To stay informed on daily fluctuations, be sure to check the Louvain-la-Neuve UV Index.

Maximum UV Index Levels in Louvain-la-Neuve for September

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

September in Louvain-la-Neuve welcomes a delightful shift in brightness, boasting 319 hours of sunshine. As summer's lingering warmth fades, this month stands out with a significant drop compared to the peak of July's 406 hours. Despite this decline, September maintains a vibrant aura, surpassing the slightly less sunny October at 240 hours. The transition from the dense sunshine of summer to the crisp beginnings of autumn is beautifully marked by this month's radiant yet mellow glow, encapsulating the essence of change that defines the Belgian climate as it gracefully yields to the cooler months ahead.

Monthly Sunshine Duration in Louvain-la-Neuve: September Highlighted

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

Chance of Sun in Louvain-la-Neuve During September

As September rolls into Louvain-la-Neuve, the chances of sunny weather show a promising 36% likelihood, which marks a slight uptick from the summer months. Following the peak of 49% in April for springtime sunshine, September’s weather hints at a transition, balancing summer's warmth with autumn's arrival. Although it trails behind the earlier months, this percentage demonstrates that the lingering warmth of summer still offers some bright days as the city prepares for cooler days ahead. In contrast to the dimmer prospects of October and the winter months, September shines as a fading yet cherished opportunity for sun-seekers in this charming Belgian locale.

Percentage of Sunny Days in September in Louvain-la-Neuve

The chart illustrates the percentage of sunny days in Louvain-la-Neuve 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 Louvain-la-Neuve experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec10%31%39%49%33%33%33%29%36%31%24%16%
Data source: Louvain-la-Neuve September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Louvain-la-Neuve in September

As summer fades and September arrives in Louvain-la-Neuve, Belgium, daylight starts to wane, settling at approximately 12 hours each day. This marks a gentle transition from the sun-soaked days of June, which boasts the year's longest daylight at 16 hours, down to the shorter months ahead. Notably, the progression from August's 14 hours to September's shorter days signals an inevitable shift towards autumn, a rhythm mirrored in nature. As we move into October, daylight decreases further to 10 hours, setting the stage for the colder months ahead. The gradual ebb of daylight in September not only heralds the onset of fall but also invites a cozy embrace of the changing season.

Average Daylight Hours in Louvain-la-Neuve for September

The chart illustrates the variation in daylight duration in Louvain-la-Neuve throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 30m10h 2m11h 55m13h 50m15h 31m16h 23m15h 55m14h 25m12h 34m10h 39m8h 56m8h 1m
Data source: Louvain-la-Neuve daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Louvain-la-Neuve

As summer gracefully transitions into autumn, September in Louvain-la-Neuve sees a gentle decline in average wind speed, dropping to 3.0 m/s (7 mph). This subtle shift signals a change in the season’s character, following a consistent pattern observed throughout the warmer months when wind speeds hovered around 3.4 m/s (8 mph). While September experiences the softest breezes of the year, it's a time of preparation for the brisker winds that will accompany the approaching months. The winds in September are not just a whisper of the upcoming chill; they create an inviting atmosphere perfect for leisurely walks and reflections amidst the changing foliage, reminding us that nature is in a state of continuous transition.

Average September Wind Speed in Louvain-la-Neuve

The chart displays monthly wind speed patterns in Louvain-la-Neuve, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.44.64.13.44.42.83.43.43.0 m/s4.43.44.2
Data source: Louvain-la-Neuve September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Louvain-la-Neuve Compares to Other Months

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

September and January present stark contrasts in weather conditions. In September, temperatures range from a mild 4°C (39°F) to a warm 33°C (91°F), with an average of 15°C (60°F). The month experiences around 58 mm (2.3 in) of precipitation over about 10 days, and humidity hovers around 82%. In contrast, January is much colder, with temperatures dipping as low as -7°C (20°F) and peaking at 14°C (57°F), leading to an average of only 4°C (39°F). The winter month sees slightly more precipitation at 65 mm (2.6 in) across 12 days, along with higher humidity levels at 91%. For a closer look at the winter conditions, check out the Louvain-la-Neuve weather in January.

The weather in September is notably warmer, with average temperatures reaching around 15°C (60°F) and maximums soaring up to 33°C (91°F), while February experiences a chillier atmosphere with an average of just 5°C (42°F) and highs of 19°C (66°F). September has a lower humidity level at 82%, which contributes to a more comfortable heat, compared to February’s higher humidity of 89%, making the cold feel even crisper. Additionally, precipitation is slightly more frequent in February, occurring over 12 days with a total of 70 mm (2.7 in), while September sees about 58 mm (2.3 in) over 10 days. For more specific details about February weather, you can visit Louvain-la-Neuve weather in February.

When comparing the weather in September and March, September tends to be much warmer, with average temperatures reaching 15°C (60°F) and a maximum of 33°C (91°F). In contrast, March experiences cooler temperatures, with an average of 7°C (45°F) and a high of only 23°C (74°F). Both months see significant humidity, with September at 82% and March slightly higher at 87%. Additionally, March tends to have more precipitation, with 71 mm (2.8 in) over 14 days compared to September’s 58 mm (2.3 in) across 10 days. For more detailed insights into the weather patterns, you can check out Louvain-la-Neuve weather in March.

In September, the weather typically ranges from a chilly minimum of 4°C (39°F) to a warm maximum of 33°C (91°F), with an average temperature of around 15°C (60°F). While experiencing about 58 mm (2.3 in) of rainfall over 10 days, the humidity remains relatively high at 82%. In contrast, April tends to be cooler, starting with minimum temperatures dropping to -4°C (26°F) and peaking at 27°C (81°F), averaging 10°C (50°F). It features less precipitation, totaling around 36 mm (1.4 in) over 8 days, and a slightly higher humidity level of 85%. For more insights on April weather, visit Louvain-la-Neuve weather in April.

When comparing the weather in September to that of May, both months feature similar humidity levels at 82%, which contributes to a relatively muggy atmosphere. September tends to be warmer overall, with average temperatures reaching 15°C (60°F) and maximums peaking at 33°C (91°F). In contrast, May has slightly cooler averages at 13°C (57°F) and maximums of 31°C (87°F). Both months experience comparable amounts of precipitation; September accumulates 58 mm over about 10 days, while May sees 60 mm spread across 13 days. For more details on May weather specifically, you can check Louvain-la-Neuve weather in May.

When comparing the weather in September and June, both months can experience similar maximum temperatures reaching up to 33°C (91°F). However, September generally starts cooler with a minimum temperature of 4°C (39°F), rising to an average of 15°C (60°F), while June begins at a higher minimum of 7°C (45°F) and has a warmer average of 18°C (65°F). In terms of precipitation, June is slightly wetter with 72 mm (2.8 in) falling over about 11 days, compared to September's 58 mm (2.3 in) over 10 days, while both months maintain a consistent humidity level of 82%. For more details on the June weather, you can visit Louvain-la-Neuve weather in June.

In comparing the weather between September and July, it becomes clear that September exhibits a broader temperature range, with minimums dipping as low as 4°C (39°F) and maximums reaching up to 33°C (91°F). The average temperature in September is 15°C (60°F), making it cooler overall than July, where temperatures range from a minimum of 8°C (46°F) to a peak of 39°C (102°F) and an average of 19°C (66°F). Precipitation in September is slightly less pronounced at 58 mm (2.3 in) over about 10 days, while July experiences 74 mm (2.9 in) across 11 days, suggesting that July is generally wetter. Humidity levels are fairly similar, with September at 82% and July slightly lower at 80%. For further details about July's weather, you can check Louvain-la-Neuve weather in July.

In comparing the weather of September to August, September presents cooler temperatures, with a minimum of 4°C (39°F) and an average of 15°C (60°F), while August features warmer temperatures, dropping only to 7°C (46°F) and averaging 19°C (66°F). The maximum temperatures are also notably different, with September reaching a peak of 33°C (91°F) compared to August's higher maximum of 36°C (97°F). Precipitation is slightly less in September, totaling 58 mm (2.3 in) over about 10 days, while August experiences more rainfall at 84 mm (3.3 in) across 14 days. Humidity remains higher in September at 82%, compared to August's 76%. For a more detailed look at August's climate, visit Louvain-la-Neuve weather in August.

In September, the weather experiences a significant range, with minimum temperatures as low as 4°C (39°F) and highs reaching up to 33°C (91°F), averaging around 15°C (60°F). The month sees approximately 58 mm (2.3 in) of precipitation spread out over about 10 days, with humidity levels at 82%.

Conversely, October brings cooler conditions, with temperatures dipping further, featuring minimums of 1°C (35°F) and a moderate maximum of 25°C (77°F), resulting in an average of 12°C (54°F). This month also tends to be wetter, accumulating around 78 mm (3.1 in) of rain over 13 days, coupled with a rise in humidity to 89%. For more detailed insights into the weather specifics, you can check Louvain-la-Neuve weather in October.

September and November exhibit notable contrasts in weather. September experiences a broader temperature range, with minimums of 4°C (39°F), average highs around 15°C (60°F), and occasional peaks of 33°C (91°F). This month sees relatively high humidity levels at 82% and about 58 mm (2.3 in) of precipitation over roughly 10 days. In contrast, November brings cooler temperatures, with minimums dipping to -3°C (28°F) and average readings around 7°C (45°F). Maximums reach a milder 18°C (65°F), while humidity rises to 92%. Precipitation remains consistent with 57 mm (2.3 in) over 11 days. For more details, you can check Louvain-la-Neuve weather in November.

In September, the weather is notably warmer, with temperatures ranging from a minimum of 4°C (39°F) to a maximum of 33°C (91°F), and an average of 15°C (60°F). This month sees moderate precipitation of 58 mm (2.3 in) over about 10 days, along with relatively high humidity at 82%. In contrast, December brings cooler conditions, with temperatures dropping to a minimum of -4°C (24°F) and an average of just 5°C (42°F), peaking at 15°C (59°F). The precipitation increases to 92 mm (3.6 in) across 17 days, and humidity rises slightly to 92%. For a closer look at December's weather conditions, you can visit Louvain-la-Neuve weather in December.

Compare Louvain-la-Neuve's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Louvain-la-Neuve

As September unfolds in Louvain-la-Neuve, the weather begins to shift, offering a delightful blend of warmth and refreshing coolness. With temperatures gradually decreasing from the summer highs, this month presents a comfortable average that makes outdoor activities enjoyable, albeit sweated occasionally with 82% humidity. While brief showers may grace the landscape on about ten days, the overall precipitation remains modest, allowing plenty of time to soak up the vibrant autumn scenery. This transitional month sets the stage for the crispness of fall while still holding onto the remnants of summer's embrace. For more detailed insights on weather patterns throughout the year, explore the section on Louvain-la-Neuve Climate.