Last updated: August 21, 2025
September in Spa, Belgium offers a delightful mix of mild weather and refreshing rain. The maximum temperature peaks at 32°C (90°F), creating warm days perfect for outdoor activities. On average, temperatures hover around a comfortable 14°C (58°F), while cool nights can drop to as low as 2°C (36°F). With 74 mm (2.9 in) of rain spread over 10 days, the month sees a fair share of precipitation, contributing to the region's lush greenery. High humidity levels at 81% enhance the fresh ambiance, making September an inviting time to explore the scenic beauty of Spa.
In September, Spa, Belgium begins to transition into autumn, showcasing a delightful range of temperatures that strike a balance between the lingering warmth of summer and the coolness of fall. With daily minimums around 2°C (36°F) and averages reaching 14°C (58°F), the air takes on a crisp freshness, making it an ideal time for outdoor adventures. The maximum temperatures can still soar up to 32°C (90°F), offering plenty of sunny days to enjoy. This month is characterized by a gentle decline in temperatures from the sweltering summer highs, providing an inviting atmosphere for both relaxation and exploration in this picturesque town.
September in Spa, Belgium experiences a moderate precipitation level of 74 mm (2.9 in), making it one of the drier months as the autumn season begins to unfold. With rainfall spread over approximately 10 days, this period sees less frequent but still notable showers compared to the wetter months of March and December. The shift from summer to autumn brings a slight decrease in precipitation, reflected in both the amount and the number of rainy days. This trend suggests that while the region doesn't completely escape the rain, the gentle transition into fall offers a welcome reprieve from the heavier downpours of the preceding months. Overall, September serves as a reminder of the changing seasons, with rainfall mellowing as nature prepares for the crisp days ahead.
In September, Spa, Belgium experiences a notable uptick in humidity, reaching 81%, a significant rise from the drier summer months of July and August, which recorded 72% and 71% respectively. This increase marks a shift towards the wetter fall season, creating a crisp yet refreshing atmosphere as the region transitions. September's humidity remains lower than the cold winter months, which peak at an impressive 92% in December, but it sets the stage for the dampness characteristic of autumn. Overall, the trend highlights Spa's varied climate, where the air thickens as summer fades and the vibrant hues of fall emerge.
As summer fades into autumn in Spa, Belgium, the September UV Index reflects a decrease to 6, indicating high exposure levels. This marks a slight decline from the very high indices seen during the peak summer months of June and July, both rated at 8. While the burn time increases to 25 minutes, it's essential to remain vigilant, as UV rays can still pose a risk. Compared to earlier months like May, where the UV Index reached its peak, September's reading serves as a reminder that even as the season changes, sun safety should remain a priority. For a more detailed outlook on UV exposure throughout the year, explore the Spa UV Index.
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In September, Spa, Belgium enjoys a delightful shift as the sunny days begin to dwindle, basking in 319 hours of sunshine. This month marks a transition from the peak brightness of July and June, where residents and visitors relished over 400 hours of sunshine, to a gentler embrace of late-summer warmth. As the vibrant hues of autumn begin to emerge, September's sun still offers a generous glow, making it a splendid time for outdoor activities before the chill of October sets in with only 240 hours of brightness on the horizon. This trend illustrates how September serves as a bridge between the sun-kissed days of summer and the cozy, overcast months of fall, inviting everyone to soak in the last remnants of summer's warmth.
In September, Spa, Belgium, experiences a notable 38% chance of sunny weather, making it one of the more promising months for sunlight in the year. This percentage reflects a gradual increase from the summer months, with July and August offering just 32% and 28% respectively. As autumn approaches, the likelihood of sunshine slightly dips compared to the vibrant spring months, where April peaks at 43%. Nonetheless, September stands out as a transition point, presenting a decent opportunity for outdoor activities while enjoying the mild temperatures of early fall. Whether you’re planning a leisurely stroll or a lively festival, the sun's prevalence in September makes it a charming time to visit this picturesque Belgian town.
In Spa, Belgium, the arrival of September brings a gentle transition in daylight duration, offering around 12 hours of sunlight each day. This marks a gradual decline from the longer summer days of June, which bask in 16 hours of light, as well as from July and August, both averaging 15 and 14 hours respectively. September serves as a bridge, hinting at the approaching autumn as daylight diminishes steadily toward 10 hours in October. As the year progresses, Spa's daylight ebbs, creating a rhythmic cycle where longer days give way to cozy, shorter ones, perfect for enjoying the crisp fall ambiance.
As summer transitions to autumn in Spa, Belgium, September brings a gentle breeze with an average wind speed of 2.8 m/s (6 mph), matching the calmness of June. This serene wind is a notable change from the more spirited gusts of earlier months, peaking at 4.7 m/s (11 mph) in February and consistently maintaining an active pace through the early part of the year. With the arrival of September, the winds soften, creating a tranquil atmosphere ideal for leisurely strolls amidst the changing colors of nature. As autumn approaches, one can anticipate a gradual increase in wind speed again, with October ramping up to 4.5 m/s (10 mph), hinting at the season's forthcoming dynamic shifts. Overall, September serves as a peaceful lull, allowing the landscape to ready itself for the vibrant transformations of fall.
Weather in Spa varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Spa, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present strikingly different weather patterns. In September, temperatures can range from a comfortable minimum of 2°C (36°F) to a warm maximum of 32°C (90°F), with an average of 14°C (58°F). The month experiences about 74 mm (2.9 in) of precipitation over approximately 10 days, accompanied by a humidity level of 81%. In contrast, January is significantly colder, with temperatures dipping as low as -12°C (10°F) and peaking only at 12°C (54°F), averaging around 2°C (36°F). It also sees increased precipitation of 100 mm (3.9 in) over 15 days and a higher humidity level of 91%. For a more detailed look at the weather conditions during this month, you can check out Spa weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a refreshing 2°C (36°F) at night to a warm 32°C (90°F) during the day, with an average of 14°C (58°F). This month sees about 74 mm (2.9 in) of precipitation over 10 days and a humidity level of 81%, lending a mild and somewhat humid atmosphere.
In stark contrast, February experiences much colder conditions, with temperatures dipping to as low as -11°C (13°F) and peaking at 20°C (68°F), averaging around 4°C (39°F). It is wetter than September, with 91 mm (3.6 in) of precipitation distributed across 13 days, and a higher humidity of 90%. For an in-depth look at Spa's unique weather during this month, visit Spa weather in February.
September and March exhibit contrasting weather patterns. September boasts a warm average temperature of 14°C (58°F), with highs reaching up to 32°C (90°F). The month, however, experiences considerable humidity at 81% and sees around 74 mm (2.9 in) of precipitation over 10 days. In stark contrast, March features a much cooler climate, with average temperatures at 6°C (43°F) and a low that can plunge to -12°C (10°F). March is also wetter, recording 108 mm (4.2 in) of precipitation over 16 days, accompanied by a slightly higher humidity level of 87%. For more detailed information about conditions in March, check out Spa weather in March.
September and April showcase distinct weather patterns, reflecting the transition between summer and autumn in the case of September, and a gradual shift from winter to spring in April. In September, temperatures can swing from a brisk minimum of 2°C (36°F) to a pleasant maximum of 32°C (90°F), with an average of 14°C (58°F). The month experiences about 74 mm (2.9 in) of precipitation over 10 days, coupled with a humidity level of 81%. In contrast, April sees cooler temperatures, ranging from a minimum of -4°C (24°F) to a maximum of 26°C (79°F), with an average of 9°C (48°F). Precipitation is lighter, totaling 45 mm (1.8 in) across 9 days, but humidity is slightly higher at 84%. Overall, while both months experience rain and humidity, September tends to offer warmer temperatures and more variability. For more detailed information about April weather, you can check out Spa weather in April.
When comparing the weather in September and May, September tends to feature a wider range of temperatures, with a minimum of 2°C (36°F) and a maximum of 32°C (90°F), leading to an average temperature of 14°C (58°F). In contrast, May has slightly cooler temperatures, with a minimum of -1°C (31°F) and a maximum of 30°C (87°F), averaging 12°C (55°F). Precipitation is somewhat more prominent in May, totaling 81 mm (3.2 in) over 15 days, compared to September's 74 mm (2.9 in) over 10 days. Humidity levels are also quite similar, with September at 81% and May slightly lower at 77%. For more detailed information, you can check Spa weather in May.
In comparing the weather between September and June, we observe a notable variation in temperatures and precipitation. September features a broader temperature range, with minimums dropping to 2°C (36°F) and maximums reaching up to 32°C (90°F), resulting in an average temperature of 14°C (58°F). In contrast, June maintains milder nights with a minimum of 6°C (43°F) and slightly warmer days, averaging 17°C (63°F). While both months experience significant rainfall, September has 74 mm (2.9 in) over about 10 days, whereas June sees a higher total of 91 mm (3.6 in) across 13 days. Additionally, September has higher humidity at 81%, compared to June's 74%. For more details on June weather, you can refer to Spa weather in June.
When comparing the weather in September and July, we see notable differences in temperature and precipitation patterns. In September, temperatures range from a minimum of 2°C (36°F) to a maximum of 32°C (90°F), with an average of 14°C (58°F). This month experiences approximately 74 mm (2.9 in) of precipitation over about 10 days, accompanied by a higher humidity level of 81%. In contrast, July tends to be warmer, with minimum temperatures of 7°C (44°F) and maximums reaching up to 38°C (101°F), averaging around 18°C (64°F). Although July is warmer, it has slightly more precipitation at 97 mm (3.8 in) spread over 12 days and a lower humidity of 72%. For those interested in detailed weather specifics, you can visit Spa weather in July.
In comparing the weather of September and August, September tends to be cooler with temperatures ranging from a minimum of 2°C (36°F) to a maximum of 32°C (90°F), while August experiences warmer temperatures, with a minimum of 6°C (42°F), averaging 18°C (64°F), and peaking at 35°C (95°F). August also sees a higher amount of precipitation at 83 mm (3.3 in) over 16 days compared to September's 74 mm (2.9 in) across 10 days, suggesting that rainfall is more frequent in August. Additionally, the humidity is higher in September at 81% compared to 71% in August. To explore more about the weather specifics, visit Spa weather in August.
In comparing the weather of September and October, we see a notable shift. September experiences a wider range of temperatures, with a minimum of 2°C (36°F) and a maximum of 32°C (90°F), resulting in an average of 14°C (58°F). In contrast, October brings cooler conditions, featuring a minimum of 1°C (33°F) and a maximum of 24°C (75°F), averaging 11°C (52°F). Additionally, October tends to be wetter, with 96 mm (3.8 in) of precipitation over 15 days, compared to September's 74 mm (2.9 in) over 10 days. The humidity also increases slightly from 81% in September to 88% in October. For more detailed information, you can check the Spa weather in October.
September and November weather present a notable contrast in temperature and conditions. In September, temperatures can reach a comfortable high of 32°C (90°F) during the day, with an average of 14°C (58°F) and low temperatures rarely dropping below 2°C (36°F). The month experiences around 74 mm (2.9 in) of precipitation over approximately 10 days, along with relatively high humidity at 81%.
In comparison, November sees a significant drop in temperature, with highs only reaching 18°C (64°F) and lows plunging to -4°C (24°F). The average temperature settles at a cooler 6°C (43°F). Despite slightly lower precipitation at 71 mm (2.8 in) over 12 days, the humidity rises to 91%, creating a damp, chilly atmosphere. For more details on the weather during this month, you can check Spa weather in November.
September and December present notably contrasting weather conditions. In September, temperatures range from a minimum of 2°C (36°F) to a maximum of 32°C (90°F), with an average of 14°C (58°F). This month experiences 74 mm (2.9 in) of precipitation over about 10 days, alongside an humidity level of 81%. In contrast, December sees significantly cooler temperatures, with a minimum of -5°C (23°F) and an average of just 4°C (39°F), peaking at 14°C (57°F). Additionally, precipitation increases substantially to 139 mm (5.5 in), occurring over 21 days, and the humidity rises to 92%. For more information on Spa weather in December, visit Spa weather in December.
As summer transitions to autumn, September in Spa brings a refreshing change, marked by significantly cooler temperatures and an increase in moisture. While days are still warm enough to enjoy outdoor activities, the crisp mornings hint at the approaching chill of winter. The humidity levels can make the air feel heavier, especially during weather changes influenced by the 74 mm of precipitation that may occur over approximately 10 days. Unlike the hotter and drier summer months, September offers a more temperate climate, inviting visitors to explore the scenic beauty of Spa while embracing the seasonal shift. For more detailed information on what to expect, visit Spa Climate.