Last updated: August 27, 2025
September in Haarlem, Netherlands offers a charming blend of warm days and cool nights, with maximum temperatures reaching 27°C (81°F) and an average of 16°C (60°F). As summer transitions to autumn, the city experiences a refreshing drop to minimum temperatures of 7°C (45°F). With an average humidity of 83%, visitors might feel the crispness in the air, complemented by around 93 mm (3.7 in) of precipitation spread over 12 days. Whether you're strolling through the historic streets or enjoying the local parks, September presents a delightful time to experience Haarlem's vibrant atmosphere.
As September unfolds in Haarlem, Netherlands, the summer warmth begins to wane, ushering in a shift towards cool, crisp days. The temperatures during this month range from a minimum of 7°C (45°F) to a comforting maximum of 27°C (81°F), with an average of 16°C (60°F), making it a delightful time for outdoor activities. This transitional period showcases a significant drop from the sweltering highs of August, yet still retains a pleasant charm that invites locals and visitors alike to enjoy the beautiful early autumn scenery. As the month progresses, the days grow shorter and the air carries an unmistakable hint of the forthcoming fall, setting the stage for the vibrant hues that await in October.
September in Haarlem, Netherlands, marks a notable transition as summer wanes, bringing an average precipitation of 93 mm (3.7 in) over approximately 12 days of rain. This inflow is slightly lower than August's substantial 99 mm, which tends to set the stage for the wet autumn months ahead. Interestingly, while September's rainfall is significant, it still falls short of the upcoming peak in October, which reaches 115 mm. This pattern indicates a gradual shift towards wetter conditions, with September acting as a bridge between the lush summer and the more intense precipitation that characterizes the autumn season. The relatively consistent rainfall days throughout these months reflect the changing climate, providing essential moisture for the lush landscapes that define Haarlem.
In September, Haarlem experiences a slight uptick in humidity, with levels reaching 83%. This rise marks a subtle shift from the drier summer months of July and August, which recorded the year’s lowest humidity at 80% and 78%, respectively. As the region transitions into autumn, humidity begins to approach the higher levels observed throughout the winter months, starting in October at 86%. Overall, September serves as a reminder of nature’s rhythm, bringing a refreshing blend of warmth and moisture before the colder months set in, as the air begins to feel richer and more alive.
As summer fades into autumn in Haarlem, September presents a moderate UV Index of 5, indicating a need for cautious sun exposure. With a burn time of 30 minutes, it’s essential to enjoy the lingering warmth while protecting your skin, especially as outdoor activities shift from beach days to strolls through the city. This marks a notable decrease from the intense UV levels of 7 and 8 seen in the peak summer months of July and August, where the sun's rays prompted more frequent vigilance. As we transition into October, the UV Index continues to drop, reflecting the changing season and signaling a move toward lower sun exposure. For more detailed information on UV patterns, visit Haarlem UV Index.
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September basks in Haarlem’s warm embrace as the summer days gradually transition toward autumn. With 326 sunshine hours, this month stands out as a beautiful capstone to the brighter months preceding it. As the sun continues to linger, visitors can still enjoy longer days compared to the approaching chill of October, which sees a drop to 239 hours. The gradual decline in sunlight from a peak in July (423 hours) highlights the change of seasons, yet September retains a comforting glow. This seasonal dance not only enhances the vibrant ambiance of the city but also invites outdoor exploration, making it a perfect time to relish the lingering warmth before winter sets in.
As summer fades into autumn, the likelihood of sunny weather in September in Haarlem shows a slight decline, with the chance of sunshine standing at 32%. This marks a dip from the more vibrant summer months of July and August, both at 36%. The transition from summer to autumn brings a shift in weather patterns, where the warmth gradually gives way to cooler, more variable conditions. While September does not boast the highest percentages of sunshine, it still retains enough brightness to delight those looking to enjoy the last remnants of summer's warmth. Overall, September serves as a gentle bridge between the sunny days of summer and the cooler, cloudier weeks of autumn.
As September arrives in Haarlem, the city continues its transition towards autumn, with daylight lasting approximately 12 hours. This represents a gentle decline from the summer months, where light peaks at 16 hours in June and July, creating a vibrant atmosphere filled with long evenings and outdoor activities. Transitioning into September, days begin to shorten, following the trend established earlier in the year—starting at 8 hours in January and gradually increasing until May. The steady decrease in daylight highlights the shifting seasons, inviting an opportunity to embrace the cozy charm of fall while still enjoying the residual warmth of the summer sun.
As September unfolds in Haarlem, the gentle whispers of the wind average around 4.3 m/s (10 mph), marking a subtle transition from the breezy summer months. This slight decrease from August's 5.3 m/s (12 mph) reflects the arrival of autumn, as the winds begin to calm down after the warmer months. The trend this year showcases a gradual decline in wind speed through late summer, providing a serene backdrop for those taking leisurely strolls along the picturesque canals. However, as October approaches, the winds are expected to pick up again, hinting at the brisk breezes that characterize the fall season. This rhythmic ebb and flow of wind adds a unique charm to Haarlem, making each month distinctly memorable.
Weather in Haarlem varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Haarlem, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather. September boasts a mild climate with temperatures ranging from a minimum of 7°C (45°F) to a maximum of 27°C (81°F), and the average temperature settles at around 16°C (60°F). This month experiences higher precipitation levels of 93 mm (3.7 in) over 12 days, alongside a humidity of 83%. In contrast, January is much colder, with temperatures dipping as low as -4°C (26°F) and averaging only 5°C (42°F). The maximum temperature in January reaches 12°C (55°F), and while precipitation is lower at 62 mm (2.4 in) over 13 days, the humidity is slightly higher at 87%. For those interested in a deeper look at January weather, you can find more information here: Haarlem weather in January.
September and February present contrasting weather conditions. In September, temperatures range from a mild 7°C (45°F) at night to a comfortable 27°C (81°F) during the day, with an average of 16°C (60°F). The month experiences an average precipitation of 93 mm (3.7 in) over 12 days, contributing to a humidity level of 83%. In stark contrast, February offers much colder temperatures, dropping to a minimum of -7°C (19°F) and peaking at 16°C (61°F), with an average temperature of only 5°C (42°F). February sees less precipitation at 71 mm (2.8 in), yet maintains a slightly higher humidity at 87%. For more details on the February weather specifics, you can check this link: Haarlem weather in February.
When comparing the weather in September and March, notable differences emerge. September enjoys a milder climate with average temperatures around 16°C (60°F) and highs reaching up to 27°C (81°F). In contrast, March presents a chillier atmosphere, with average temperatures only at 7°C (44°F) and minimums potentially dropping to -7°C (19°F). Precipitation levels are relatively high in both months, with September experiencing 93 mm (3.7 in) over 12 days, while March sees slightly less at 71 mm (2.8 in) across 14 days. Humidity is comparable, hovering around 83% in September and slightly higher at 86% in March. For more specifics about March weather, check out Haarlem weather in March.
When comparing the weather in September and April, significant differences emerge in temperature and precipitation. In September, temperatures range from a cool minimum of 7°C (45°F) to a warm maximum of 27°C (81°F), with an average of 16°C (60°F). In contrast, April experiences much cooler weather, with minimum temperatures dropping to 1°C (34°F) and a mild maximum of 25°C (77°F), averaging just 9°C (49°F). Additionally, September sees higher precipitation levels at 93 mm (3.7 in) over 12 days, whereas April has a lighter total of 43 mm (1.7 in) over 10 days. Humidity is relatively high in both months, with September at 83% and April at 85%. For more details on April weather, you can check Haarlem weather in April.
In comparing the weather of September and May, September generally showcases a warmer climate with average temperatures around 16°C (60°F) and maximums reaching up to 27°C (81°F), while May has a cooler average of 12°C (55°F) and similar highs. Both months experience a maximum temperature of 27°C, but September’s minimum is slightly higher at 7°C (45°F) compared to May's 4°C (40°F). Rainfall is another differentiator; September sees more precipitation at 93 mm (3.7 in) over 12 days, whereas May has a drier spell with only 54 mm (2.1 in) across 11 days. Humidity levels are quite similar, with September at 83% and May at 84%. For more detailed information on May weather, visit Haarlem weather in May.
In comparing the weather between September and June, we observe some notable differences. September features a slightly broader temperature range with lows around 7°C (45°F) and highs reaching 27°C (81°F), while June begins warmer, with minimum temperatures of 9°C (48°F) and maximums up to 30°C (86°F). Although both months experience moderate humidity, September is a bit more humid at 83%, compared to June's 81%. Precipitation in September is also higher, averaging 93 mm (3.7 in) over 12 days, while June sees less rain at 74 mm (2.9 in) spread across 11 days. For more detailed information, you can explore Haarlem weather in June.
In comparing the weather of September and July, September generally presents milder temperatures, with a minimum of 7°C (45°F) and an average of 16°C (60°F), while July boasts warmer conditions with a minimum of 11°C (52°F) and an average of 18°C (64°F). July also features higher maximum temperatures, reaching up to 33°C (92°F), compared to September's peak of 27°C (81°F). Precipitation levels are slightly higher in September, totaling 93 mm (3.7 in) over 12 days, while July sees 73 mm (2.9 in) across 14 days. Humidity levels are fairly comparable, with September at 83% and July at 80%. For more detailed insights into July weather, visit Haarlem weather in July.
In comparison to August, September experiences cooler temperatures, with average highs of 27°C (81°F) compared to August's 30°C (87°F). The minimum temperatures in September drop to 7°C (45°F), while in August, they start at a milder 11°C (52°F). Both months have significant precipitation, with September receiving 93 mm (3.7 in) over 12 days, slightly less than August's 99 mm (3.9 in) across 15 days. Additionally, September's humidity is higher at 83%, compared to August's 78%. For more detailed information, you can check Haarlem weather in August.
September and October feature notable differences in weather patterns. In September, temperatures range from a minimum of 7°C (45°F) to a maximum of 27°C (81°F), with an average of 16°C (60°F). The month experiences about 93 mm (3.7 in) of precipitation spread over 12 days, accompanied by a humidity level of 83%. In contrast, October brings cooler conditions, with temperatures dipping to a minimum of 4°C (40°F), averaging 13°C (55°F), and peaking at a maximum of 23°C (74°F). Rainfall increases to 115 mm (4.5 in) over 17 days, and humidity rises slightly to 86%. For a more detailed look at the climate, check out Haarlem weather in October.
September weather tends to be milder, with temperatures ranging from a chilly 7°C (45°F) to a comfortable 27°C (81°F), and an average of 16°C (60°F). It experiences more rainfall with a total of 93 mm (3.7 in) over about 12 days, alongside a humidity level of 83%. In contrast, November sees a significant drop in temperatures, with a minimum of 0°C (33°F) and a maximum of 17°C (63°F), resulting in an average of only 9°C (48°F). While November has less precipitation at 65 mm (2.6 in), it stretches across 15 days and has a slightly higher humidity of 87%. For more detailed information about the weather in November, you can visit Haarlem weather in November.
September and December exhibit considerable differences in weather patterns. In September, temperatures range from a mild minimum of 7°C (45°F) to a comfortable maximum of 27°C (81°F), with an average temperature of 16°C (60°F). The month experiences approximately 93 mm (3.7 in) of precipitation over about 12 days, accompanied by a humidity level of 83%. In contrast, December brings much colder conditions with temperatures dropping to a minimum of -3°C (27°F) and peaking at only 13°C (55°F), resulting in an average temperature of just 6°C (44°F). This month sees even higher precipitation, tallying 105 mm (4.1 in) over 18 days, and a slightly elevated humidity of 86%. For more details on December weather, check out Haarlem weather in December.
As summer gracefully transitions to autumn, September in Haarlem offers a harmonious blend of warm temperatures and increased humidity, distinguishing it from the preceding months. While days can still bask in the sun with highs around 27°C, the evenings cool down significantly, inviting cozy sweaters. The rainfall in September, totaling 93 mm, marks a notable rise, bringing refreshing showers that rejuvenate the landscape. With an average of 83% humidity, the city's ambiance shifts, preparing residents and visitors alike for the crispness of fall ahead. For a deeper dive into Haarlem's distinctive weather patterns, explore Haarlem Climate.