Last updated: August 27, 2025
In Willemstad, Netherlands, September weather showcases a delightful blend of warmth and humidity, with maximum temperatures reaching 31°C (89°F). While the average temperature rests at a comfortable 15°C (60°F), nights can dip to a refreshing 3°C (38°F). This month also witnesses 66 mm (2.6 in) of precipitation over approximately 11 days, contributing to the region's lush landscapes. With humidity levels hovering around 82%, September in Willemstad offers a vibrant yet cozy atmosphere, perfect for enjoying the transition from summer to autumn.
In September, temperatures in Willemstad, Netherlands, start to show a subtle transition from the sweltering summer heat to the cooler embrace of autumn. With minimums dipping to 3°C (38°F) and averages settling around 15°C (60°F), the early hints of fall are evident. The maximum temperatures can still reach a pleasant 31°C (89°F), making September a month of comfortable warmth alongside the refreshing onset of cooler evenings. This month often offers a delightful mix of warmth and crisp air, inviting outdoor adventures while showcasing the beauty of the changing seasons. As summer fades, September lays the groundwork for the cooler months ahead, making it a unique time to experience Willemstad.
In September, Willemstad experiences a moderate precipitation total of 66 mm (2.6 in), marking a noticeable shift from the wetter months of August and the upcoming October. With rain falling on 11 days, this month offers a balance, as the frequency of precipitation is lower than the summer peak but still substantial enough to maintain the region's lush allure. Following the typically wet summer, September provides a gentle transition into the autumn months, where rainfall begins to increase again, hinting at the rainfall peak in October with 89 mm (3.5 in) expected. This gradual decline in precipitation frequency is a pattern observed as the year progresses, contributing to Willemstad's dynamic climate and vibrant landscapes.
In September, humidity levels in Willemstad settle at a comfortable 82%, reflecting a slight uptick from the drier summer months. This period marks a transition as the humidity gradually begins to rise again, paving the way for the wetter months ahead. Notably, humidity has shown a steady decline from a peak of 91% in January to its lowest of 76% in August, emphasizing a seasonal ebb and flow. As autumn approaches, residents can expect a return to higher humidity levels, reminiscent of the start of the year, with October and November reaching 89% and 92% respectively. This rhythmic shift in humidity showcases the dynamic climate of Willemstad, providing a constant reminder of nature's cycles.
In September, the UV Index in Willemstad settles at a moderate level of 5, signaling a shift as summer fades into fall. This monthly average reflects a decrease from the peak summer months, where UV levels soared to 8, indicating very high exposure risks during June and July. With a burn time of 30 minutes, it's still essential to take precautions when outdoors, especially during midday. As the days grow shorter and temperatures begin to cool, September serves as a gentle reminder to stay vigilant about sun safety, even as the UV Index lowers. For more detailed insights, visit Willemstad UV Index.
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As summer wanes and September settles into Willemstad, the sunshine continues to shine brightly, offering an impressive 329 hours of daylight. This marks a notable decline from the peak of summer where July basked in 422 hours of sunlight, yet it still stands as one of the sunniest months of the year. As the vibrant hues of summer begin to fade, the transition into autumn reveals a gentle tapering pattern of daylight, reminiscent of the preceding months, such as August with 394 hours. While the days slowly shorten, there's a unique charm to September's warmth, inviting residents and visitors alike to revel in the lingering glow before the cooler months arrive.
In Willemstad, Netherlands, September typically offers a 32% chance of sunny weather, a figure that aligns closely with the summer months but suggests a subtle transition toward the cooler autumn atmosphere. The probability of sunshine slightly dips from the peak in April, which boasts a sunny likelihood of 42%, indicating that while September still enjoys decent chances for bright days, it heralds the onset of the wetter months ahead. This trend reveals that, while sunny days are still to be savored, travelers and locals alike should be prepared for the shifting weather patterns that autumn inevitably brings.
As summer fades into autumn in Willemstad, Netherlands, September brings a gentle decline in daylight hours, offering around 12 hours of sunlight each day. This transition marks a shift from the 16 hours of glorious daylight experienced in June and July, gradually tapering off towards the shorter days of October, which sees just 10 hours of light. The increasing darkness serves as a reminder of the changing seasons, as daylight shrinks from the vibrant 15 hours of May, followed by a warm 14 hours in August. With the arrival of September, residents and visitors alike can enjoy the lingering warmth of early autumn days while subtly preparing for the cozy, shorter days ahead.
As September arrives in Willemstad, Netherlands, the wind begins to let up, gently settling into a calm rhythm. With an average wind speed of 3.2 m/s (7 mph), it marks a noticeable decline from the breezier summer months, where winds hovered around 3.5 to 3.8 m/s. This shift signals the transition from summer's warmth to autumn's approach, inviting residents and visitors alike to enjoy the serene beauty of the waning days of late summer. Interestingly, September's winds set the stage for the slightly brisker patterns returning in October, which averages back up to 4.5 m/s (10 mph). The changing winds not only reflect the seasonal shifts but also add a distinct charm to the picturesque landscape of Willemstad, making each moment outdoors a delightful experience.
Weather in Willemstad varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Willemstad, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present quite contrasting weather patterns. In September, temperatures range from a minimum of 3°C (38°F) to a maximum of 31°C (89°F), with an average of 15°C (60°F), making it a much warmer month overall. The humidity sits at 82%, and there is 66 mm (2.6 in) of precipitation over about 11 days. In stark contrast, January experiences colder temperatures with a minimum of -7°C (19°F) and a maximum of 14°C (58°F), averaging just 5°C (40°F). Although January has slightly less precipitation at 59 mm (2.3 in) over 12 days, the humidity is higher at 91%. For more detailed information, you can check out Willemstad weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a mild 3°C (38°F) at night to a warm 31°C (89°F) during the day, with an average of 15°C (60°F). The month experiences about 66 mm (2.6 in) of precipitation over 11 days, accompanied by relatively high humidity at 82%. In stark contrast, February sees much cooler temperatures, with nighttime lows plummeting to -10°C (15°F) and daytime highs reaching only 18°C (65°F), averaging around 5°C (42°F). Precipitation is slightly lower at 65 mm (2.6 in) across 12 days, but humidity is higher, peaking at 89%. For a more detailed overview of the February weather, you can explore Willemstad weather in February.
In comparing the weather of September and March, we observe distinct contrasts. September boasts a warm range of temperatures with a minimum of 3°C (38°F) and a maximum of 31°C (89°F), making it generally warmer with an average of 15°C (60°F). Precipitation levels are moderate at 66 mm (2.6 in) over approximately 11 rainy days, combined with a relatively high humidity of 82%.
In contrast, March presents cooler conditions, with temperatures ranging from a minimum of -8°C (19°F) to a maximum of 22°C (72°F) and an average of 7°C (45°F). It experiences slightly higher precipitation at 70 mm (2.8 in) spread over 14 days, while humidity rises to 87%. For more details on March weather, you can visit Willemstad weather in March.
In comparing the weather between September and April, we see notable differences in temperature and precipitation. September boasts a wider temperature range, with minimums of 3°C and maximums reaching up to 31°C, while April starts chillier with lows of -2°C and highs of 27°C. Both months experience significant humidity, with September slightly lower at 82% compared to April's 85%. Precipitation is more prevalent in September, totaling 66 mm over 11 days, in contrast to April’s 43 mm across 9 days. For a more detailed look at April weather specifics, please visit Willemstad weather in April.
When comparing the weather in September and May, both months feature a similar maximum temperature of 31°C (89°F), providing warm days perfect for outdoor activities. However, September has a slightly higher average temperature of 15°C (60°F) compared to May's average of 13°C (56°F). Interestingly, both months experience the same level of precipitation at 66 mm (2.6 in), although September has one less day of rain at 11 days compared to May's 12 days. Humidity levels remain consistent in both months at 82%, contributing to a similar atmospheric feel. For more detailed information on May weather, check out Willemstad weather in May.
When comparing the weather in September and June, there are some notable differences. September tends to have a wider temperature range, with minimums reaching as low as 3°C (38°F) and maximums peaking at 31°C (89°F). In contrast, June starts off warmer, with minimum temperatures around 8°C (46°F) and highs typically around 32°C (90°F). Both months experience similar humidity levels at 82%, but September sees slightly less precipitation, averaging 66 mm (2.6 in) over 11 days compared to June's 73 mm (2.9 in) over 10 days. For a more detailed look at June weather, you can visit Willemstad weather in June.
When comparing the weather in September and July, notable differences emerge. September experiences a broader temperature range, with minimums dropping to 3°C (38°F) and maximums reaching up to 31°C (89°F), averaging around 15°C (60°F). On the other hand, July tends to be warmer, with minimums at 8°C (46°F), maximums soaring to 39°C (102°F), and an average temperature of 18°C (66°F). While both months see significant precipitation, September records about 66 mm (2.6 in) over 11 days, while July has slightly more at 77 mm (3.0 in) across 13 days. Humidity levels are also quite comparable, with September at 82% and July slightly lower at 80%. For more detailed insights into July weather, you can check Willemstad weather in July.
In August, the weather tends to be warmer, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 34°C (94°F) and an average of 19°C (66°F). The humidity level is relatively lower at 76%, but the month experiences more precipitation, totaling 85 mm (3.3 in) over 14 days. In contrast, September shows a greater temperature variation, with min temperatures dropping to 3°C (38°F) and max temperatures reaching 31°C (89°F), resulting in a cooler average of 15°C (60°F). Although September has slightly less rainfall at 66 mm (2.6 in) over 11 days, it exhibits a higher humidity level at 82%. For a detailed overview of the weather conditions, you can check Willemstad weather in August.
September generally presents a wider range of temperatures, with minimums of 3°C (38°F) and maximums reaching up to 31°C (89°F), while averaging around 15°C (60°F). In contrast, October sees cooler conditions, with minimum temperatures dropping to 2°C (36°F) and maximums capping at 26°C (78°F), leading to an average of 12°C (54°F). Additionally, October tends to be wetter, with precipitation increasing to 89 mm (3.5 in) over 14 days, compared to September's 66 mm (2.6 in) over 11 days. Humidity also rises slightly from 82% in September to 89% in October. For a detailed look at the conditions in October, you can check Willemstad weather in October.
In September, the weather is generally warmer, with temperatures ranging from a minimum of 3°C (38°F) to a maximum of 31°C (89°F) and an average of 15°C (60°F). This month experiences about 66 mm (2.6 in) of precipitation over 11 days, along with a relatively high humidity of 82%. In contrast, November brings cooler temperatures, with a minimum of -2°C (29°F), an average of 8°C (46°F), and a maximum of 19°C (66°F). Although November sees slightly less precipitation at 55 mm (2.2 in) over 12 days, it also has higher humidity at 92%. If you want more detailed information about what to expect, check this link: Willemstad weather in November.
September weather is characterized by a warm range of temperatures, with minimums around 3°C and highs reaching up to 31°C, averaging 15°C. It experiences moderate rainfall, with 66 mm over 11 days, and a relatively high humidity level of 82%. In contrast, December becomes significantly colder, with minimum temperatures dropping to -4°C and maximums peaking at 14°C, resulting in an average of just 6°C. This month also sees increased precipitation, totaling 92 mm over 17 days, and even higher humidity levels at 92%. For more details, you can check Willemstad weather in December.
As September arrives in Willemstad, the weather takes on a unique character, marked by a temperate warmth and a hint of seasonal transition. With humidity levels peaking at 82%, it's a month where the lingering summer heat still dances with the cooler autumn breezes, making it distinctly different from the hotter summer months. Though rainfall increases with 66 mm spread over about 11 days, the overall experience is refreshing rather than oppressive. For those curious about how Willemstad's weather evolves throughout the year, more detailed insights can be found in the Willemstad Climate resource.