Last updated: August 21, 2025
Experience Uccle, Belgium in September, where temperatures range from a comfortable 4°C (39°F) to a sizzling 33°C (91°F). The month boasts an average temperature of 15°C (60°F), perfect for those who enjoy mild weather. While visitors can bask in the warmth, they should also be prepared for occasional rain, with 55 mm (2.2 in) falling over 9 days, creating a lush backdrop for exploring the vibrant surroundings. With humidity levels at a notable 82%, the September climate offers a mix of charm and challenge for outdoor enthusiasts and casual wanderers alike.
In September, Uccle, Belgium, showcases a delightful transition from the sweltering summer to the cooler embrace of autumn. With minimum temperatures averaging around 4°C (39°F), the crispness of early fall begins to settle in, creating a refreshing atmosphere. Daytime highs, however, can still soar to a pleasant 33°C (91°F), offering ample opportunities for outdoor activities in the sun. The average temperature of 15°C (60°F) strikes a fine balance, typical of early autumn's mildness, as the days gradually shorten and the leaves start their stunning transformation. This month serves as a perfect reminder of the vibrant seasonal shifts in Uccle, blending the remnants of summer warmth with the invigorating coolness of fall.
In September, Uccle, Belgium, experienced a moderate precipitation total of 55 mm (2.2 in) over 9 days, marking a slight decrease from the wetter months of August and July. This suggests a transition towards the drier autumn months, with early signs of fall starting to emerge. Following the peak of summer rainfall, September's precipitation is notably lower, reflecting a drop in both intensity and frequency. However, this month's totals still contribute to a robust accumulation leading into the more rainfall-heavy October, which typically sees an uptick to 76 mm (3.0 in). Overall, September serves as a bridging month, balancing the lush wetness of summer with the crisp dryness of autumn.
As summer transitions into autumn, September in Uccle, Belgium brings a refreshing shift in humidity, settling at 82%. This slight increase from the drier month of August, which recorded a low 76%, signifies the onset of cooler, more humid days ahead. Although September's levels mirror those seen in both May and June, it's notably lower compared to the winter months of January and February, when humidity peaks at around 91%. This pattern illustrates a gradual build-up that leads into the wetter autumn season, with creeping humidity levels typical of both October and November, reaching 89% and 92%, respectively. Overall, September stands as a bridge between the lingering warmth of summer and the impending chill of winter, with its humidity reflecting the overall shift in the season.
As September rolls into Uccle, Belgium, the UV Index settles at a moderate level of 5, indicating that while sun exposure is generally safe, it's wise to take precautions, especially during peak hours. This marks a transition from the very high UV Index of 8 seen in the summer months of June and July, showcasing a gradual decrease in sunlight intensity as autumn approaches. With a recommended burn time of 30 minutes, residents can enjoy outdoor activities while keeping skin safety in mind. As the days shorten, the sun's impact becomes gentler, yet vigilance is still essential to protect against UV damage. For more insights, check out the detailed information at Uccle UV Index.
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September in Uccle, Belgium, offers a delightful transition from the vibrant summer months to the cozy embrace of autumn. With 319 hours of sunshine, it stands out as a month that still basks in the warm glow of late summer, although the hours are a noticeable dip from the 406 hours seen in July. This gradual decrease signals the inevitable approach of fall, while still providing ample opportunities for outdoor activities and scenic strolls amidst the changing foliage. As the days shorten, the rich tapestry of sunlight hours in September serves as a gentle reminder of the seasonal shift, encouraging locals and visitors alike to savor the lingering warmth before the cooler months set in.
In Uccle, Belgium, the likelihood of enjoying sunny weather in September is 36%, marking a slight uptick as summer transitions into fall. While early spring typically boasts a lower probability of sunshine, reaching only 40% in March, the chances of clear skies enter a gradual decline during the summer months, peaking at 50% in April before tapering off in the peak summer. Notably, September stands out as a month where sun-seekers can still find reasonably favorable conditions, slightly overshadowed by the subsequent cooler months that lead into winter, where the chance of sunshine dips significantly to 15% in December. Thus, September represents a crucial window for those looking to bask in the sun before the dreariness of fall sets in.
In Uccle, Belgium, the rhythm of daylight ebbs and flows beautifully throughout the year. As the summer months fade, September offers a gentle transition with approximately 12 hours of daylight, a noticeable shift from the sun-drenched days of June and July when sunlight peaked at 16 hours. This month signals the gradual retreat of long days, moving steadily towards autumn, as daylight dwindles to 10 hours by October. The interplay between the vibrant 15 hours of May and the shorter winter days reflects the natural cycle of change, inviting residents to savor the fading warmth while preparing for the cozy embrace of the season ahead.
As September arrives in Uccle, Belgium, the winds start to whisper of autumn, with an average speed of 3.0 m/s (7 mph)—a slight dip compared to the summer months. This slowdown follows a predominantly breezy summer, where winds peaked at 4.4 m/s (10 mph) in both May and January, suggesting a seasonal rhythm that is both gentle and refreshing. The transition into fall sees wind speeds gradually shifting, with October bringing a slight increase to 4.3 m/s (10 mph), hinting at the return of more robust gusts. In this serene month of September, one can enjoy the gentle breeze as it foreshadows the crisp air of the upcoming season, reflective of the natural ebb and flow of Uccle's climate.
Weather in Uccle varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Uccle, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present striking contrasts in weather. In September, the temperatures range from a chilly 4°C (39°F) at night to a warm 33°C (91°F) during the day, with an average of 15°C (60°F). The month experiences relatively moderate precipitation, totaling 55 mm (2.2 in) over about 9 days and maintains a humidity level of 82%. In contrast, January is much colder, with temperatures dropping as low as -7°C (20°F) and peaking at a mere 14°C (57°F), averaging just 4°C (39°F). Precipitation increases slightly to 65 mm (2.5 in) spread across 12 days, while humidity rises to 91%, making January feel damp and frigid. For more details on January weather, check Uccle weather in January.
The weather in September showcases a significant range, with temperatures fluctuating from a cool 4°C (39°F) at night to a warm maximum of 33°C (91°F) during the day, while averaging around 15°C (60°F). This month typically sees about 55 mm (2.2 in) of precipitation over approximately 9 days and has a humidity level of 82%.
In contrast, February's climate is markedly colder, featuring minimum temperatures that drop to -8°C (17°F) and a modest average of 5°C (42°F), peaking at 19°C (66°F). This month experiences slightly higher precipitation levels at 69 mm (2.7 in), spread over 12 days, with humidity reaching 89%. For more insights on February's weather, visit Uccle weather in February.
September and March exhibit contrasting weather patterns. In September, temperatures range from a minimum of 4°C (39°F) to a maximum of 33°C (91°F), with an average of 15°C (60°F), and a relatively lower humidity of 82%. The month experiences a total of 55 mm (2.2 in) of precipitation across 9 days. In contrast, March sees cooler temperatures with a minimum of -8°C (17°F) and a maximum of 23°C (74°F), averaging around 7°C (45°F). This month tends to be wetter, registering 70 mm (2.8 in) of precipitation over 14 days and slightly higher humidity at 87%. For a more detailed look at the weather during this time, visit Uccle weather in March.
When comparing the weather in September and April, notable differences emerge. September typically enjoys a broader temperature range, with lows of 4°C (39°F) and highs reaching a warm 33°C (91°F), resulting in an average of 15°C (60°F). In contrast, April presents cooler temperatures, featuring a minimum of -4°C (26°F) and a maximum of 27°C (80°F), with an average of 10°C (50°F). Precipitation is slightly higher in September at 55 mm (2.2 in) over 9 days, compared to April's 37 mm (1.5 in) over a similar duration of 8 days. Humidity levels are relatively similar, with September at 82% and April a touch higher at 85%. For a more detailed look at April weather, you can visit Uccle weather in April.
When comparing the weather in September and May, both months feature relatively mild temperatures and high humidity levels of 82%. September tends to be warmer overall, with average temperatures reaching 15°C (60°F) and maximums climbing as high as 33°C (91°F). In contrast, May has slightly cooler averages at 13°C (57°F) and maximums of 31°C (88°F). Interestingly, both months experience similar levels of precipitation, with September receiving 55 mm (2.2 in) over 9 days and May slightly higher at 58 mm (2.3 in) over 12 days. For a detailed look at May's weather, you can visit Uccle weather in May.
In comparing the weather between September and June, both months showcase a range of temperatures and similar humidity levels. September experiences a wider temperature range, with a minimum of 4°C (39°F) and a maximum of 33°C (91°F), while June's temperatures are slightly milder, ranging from 7°C (44°F) to a maximum of 32°C (91°F). Interestingly, despite the higher average temperature in June at 18°C (65°F) compared to September's 15°C (60°F), September tends to have slightly less precipitation, recording 55 mm (2.2 in) compared to June's 66 mm (2.6 in), although both months share the same number of rainy days at nine. For more specific information, you can check details in the link: Uccle weather in June.
In comparing the weather between September and July, we see notable differences in temperature and precipitation. September experiences a broader temperature range, with minimums around 4°C (39°F) and maximums reaching up to 33°C (91°F), giving it an average of 15°C (60°F). In contrast, July is generally warmer, with minimums at 8°C (46°F) and maximums soaring to 39°C (102°F), leading to an average of 19°C (66°F). Additionally, September sees approximately 55 mm (2.2 in) of precipitation over 9 days, while July has higher precipitation levels at 71 mm (2.8 in) over 11 days. Humidity levels are relatively similar, with September at 82% and July at 80%. For a more detailed look at July's weather specifics, visit Uccle weather in July.
September experiences a broader temperature range compared to August, with minimums dipping to 4°C (39°F) and maximums reaching 33°C (91°F). In contrast, August has milder temperatures, featuring minimums around 8°C (46°F) and maximums peaking at 36°C (97°F). Though September is cooler, it also sees slightly less precipitation at 55 mm (2.2 in) over 9 days, while August records higher rainfall of 80 mm (3.2 in) across 14 days. Humidity levels remain relatively high in both months, with September at 82% and August at 76%. For more details on August weather specifically, you can refer to Uccle weather in August.
In September, temperatures range from a cool 4°C (39°F) to a warm 33°C (91°F), with an average of 15°C (60°F). The month experiences 55 mm (2.2 in) of precipitation over about 9 days and maintains a humidity level of 82%. In contrast, October brings much cooler temperatures, with a minimum of 1°C (34°F) and a maximum of 25°C (77°F), averaging around 12°C (54°F). The rainfall increases to 76 mm (3.0 in) spread across 13 days, accompanied by a higher humidity of 89%. For more detailed insights, you can visit Uccle weather in October.
September and November exhibit distinct weather characteristics, reflecting the transition from late summer to early winter. In September, temperatures can range from a mild 4°C (39°F) at night to a warm 33°C (91°F) during the day, with an average temperature around 15°C (60°F). The month also experiences relatively lower humidity at 82% and less frequent precipitation, totaling 55 mm over 9 days.
In contrast, November sees significantly cooler temperatures, with nighttime lows dropping to -2°C (28°F) and daytime highs averaging only 18°C (65°F), leading to an overall average of 7°C (45°F). This month also brings a slight increase in precipitation to 57 mm, spread over 11 days, and higher humidity levels at 92%. For a more detailed look at the weather in this month, you can check Uccle weather in November.
In comparing the weather between September and December, a noticeable shift is evident. September offers a wider temperature range, with averages around 15°C (60°F) and maximums reaching up to 33°C (91°F), while December's temperatures are much cooler, averaging 5°C (42°F) and peaking at just 15°C (59°F). Precipitation also increases from 55 mm (2.2 in) over 9 days in September to 93 mm (3.7 in) across 17 days in December, indicating a wetter month. Additionally, December's humidity rises slightly to 92% compared to September’s 82%. For more specific details about the December weather in Uccle, you can refer to Uccle weather in December.
As September unfolds in Uccle, the weather transitions into a more moderate rhythm compared to the sweltering heights of summer. With temperatures ranging from refreshing coolness to warm afternoon peaks, this month offers a pleasant blend of warmth and chill. While occasional showers bring necessary moisture—totaling around 55 mm over nine days—the high humidity levels at 82% can create a softer, more enveloping atmosphere. Overall, September serves as a gentle bridge from the vibrant heat of summer to the crispness of autumn, inviting residents and visitors alike to enjoy its varied climatic tapestry. For a deeper understanding of what to expect year-round, explore the detailed insights at Uccle Climate.