September Weather in Amersfoort, Netherlands

Last updated: August 27, 2025

September in Amersfoort, Netherlands offers a diverse weather experience, characterized by a maximum temperature reaching 31°C (88°F), while the average settles comfortably at 15°C (59°F). The month starts off warm but can dip to a minimum of 3°C (38°F), showcasing the transitional nature of early autumn. Visitors can expect about 70 mm (2.8 in) of rainfall over 11 days, contributing to an 83% humidity level that adds a touch of briskness to the air. Whether you’re exploring the charming canals or enjoying local festivities, September’s varied climate sets the stage for memorable experiences in this picturesque Dutch city.

September Temperature in Amersfoort

In September, Amersfoort, Netherlands, experiences a refreshing transition as summer yields to autumn. With minimum temperatures settling around 3°C (38°F) and averages peaking at 15°C (59°F), the weather remains comfortably mild, while maximums can still warm up to 31°C (88°F), reminiscent of late summer days. This month marks a noticeable shift compared to the sweltering heights of July and August, yet it maintains a pleasant warmth ideal for outdoor activities and enjoying the changing seasons. As the days grow shorter, the crispness in the air invites locals and visitors alike to embrace the beauty of the Dutch landscape painted with autumn hues.

September Weather in Amersfoort: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Amersfoort, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Amersfoort, 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).
JanFebMarAprMayJunJulAugSepOctNovDec394044495664656559544541
Data source: Temperature data for Amersfoort generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Amersfoort

September in Amersfoort brings an average precipitation of 70 mm (2.8 in), falling over approximately 11 days. This marks a slight decrease from the preceding month of August, which typically sees the highest rainfall at 87 mm (3.4 in). The early autumn weather establishes a pattern where precipitation begins to stabilize, transitioning from the summer's frequent showers while still showcasing a moderate amount of rain. As the days grow shorter and cooler, September's rainfall sets the stage for the wetter months ahead, with October poised to bring about 86 mm (3.4 in) of rain over 14 days. This gradual shift highlights the changing seasons in the Netherlands, as summer's deluge gives way to fall's steady drizzles.

September Precipitation Trends in Amersfoort

The chart displays monthly precipitation patterns in Amersfoort, 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 Amersfoort, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec597274426373758770865187
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Amersfoort

In September, Amersfoort experiences a noticeable shift in humidity, with levels averaging at 83%. This marks a slight increase from the drier summer months of July and August, which held steady at 75%. As autumn approaches, the humidity begins to rise again, echoing the trend seen earlier in the year, where the colder months of October and November revert to higher averages of 86% and 87%, respectively. Overall, September serves as a transitional month, bridging the lower humidity of summer and the wetter chill of fall, making it a time of refreshing change in the Netherlands.

September Average Humidity in Amersfoort

This chart illustrates the average monthly humidity levels in Amersfoort, 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 Amersfoort is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec88%88%86%84%80%75%75%75%83%86%87%86%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Amersfoort

As September arrives in Amersfoort, the UV Index reflects a moderate level of exposure, sitting at 5 with a burn time of 30 minutes. This marks a shift from the high UV levels experienced in the summer months of July and August, which reached as high as 8. While sun safety remains important, the transition to autumn provides a slight reprieve from the intense sun, yet it’s still wise to be mindful of UV exposure, especially during midday hours. As the month progresses into October, the UV Index is expected to further decrease to 3. Embrace the changing season while keeping sun safety in mind! For more details, visit Amersfoort UV Index.

Maximum UV Index Levels in Amersfoort for September

The chart shows the monthly maximum UV Index (UVI) for Amersfoort 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 Amersfoort typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec124578875321
Data source: Amersfoort 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 Amersfoort

As September rolls into Amersfoort, the lingering warmth of summer begins to retreat, but the sun still graces the city with 324 hours of sunlight—an inviting farewell before autumn settles in. This month marks a noticeable dip from the vibrant summer peak of 415 hours in July, yet it outshines the earlier months, demonstrating that even as the nights grow longer, days can still be beautifully bright. Following a pattern of diminishing daylight, September's sunshine continues a trend seen throughout the year, where the sunniest months transition gently into the cooler, less illuminated period of October, which basks in just 241 hours of sunlight. The dance of light and shadow in Amersfoort paints a portrait of seasonal change, seamlessly bridging the summer's warmth with the cozy embrace of autumn.

Monthly Sunshine Duration in Amersfoort: September Highlighted

The September sunshine duration represents the total number of hours Amersfoort 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.
JanFebMarAprMayJunJulAugSepOctNovDec110h198h278h356h409h403h415h391h324h241h192h131h
Data source: Amersfoort September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Amersfoort During September

In September, Amersfoort enjoys a 32% chance of sunny weather, a figure that reflects the transition from summer to autumn. This percentage aligns closely with the preceding months of August (32%) and July (33%), suggesting a lingering warmth before the cooler, cloudier days of fall set in. Notably, the likelihood of sunshine begins to dip significantly after September, with October falling to 27%, further emphasizing the fleeting nature of summer's rays. As the season shifts, September stands out as a pivotal time when residents can still relish in some sunny days, making it an ideal month for outdoor activities before the dreariness of autumn takes hold.

Percentage of Sunny Days in September in Amersfoort

The chart illustrates the percentage of sunny days in Amersfoort 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 Amersfoort experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec17%27%35%40%30%36%33%32%32%28%23%16%
Data source: Amersfoort September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Amersfoort in September

As the seasons transition from the vibrant summer months to the crisp beginnings of autumn, September in Amersfoort, Netherlands, witnesses a gentle decline in daylight hours. With 12 hours of daylight, this month marks a significant shift from the long, sunlit days of summer, which peaked at 16 hours in June and July. The daylight gradually lessens, drawing closer to the shorter days of October's 10 hours and the 8 hours in November. This rhythmic pattern of daylight duration not only highlights the passage of time but also invites residents to savor the last warm rays before winter settles in, blending the beauty of changing seasons with the anticipation of cozy fall evenings.

Average Daylight Hours in Amersfoort for September

The chart illustrates the variation in daylight duration in Amersfoort throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 17m9h 54m11h 54m13h 57m15h 45m16h 41m16h 11m14h 34m12h 36m10h 34m8h 44m7h 45m
Data source: Amersfoort daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Amersfoort

As September arrives in Amersfoort, the average wind speed gently ebbs to 3.2 m/s (7 mph), marking a transition into the quieter breezes of autumn. This shift follows a summer where wind speeds hovered around the moderate 3.0 to 4.1 m/s range, creating ideal conditions for seasonal outdoor activities. Notably, September's wind is a notable drop from the year's earlier peaks, particularly in October, which typically sees a resurgence to 4.5 m/s (10 mph). This trend of decreasing wind speeds towards the end of summer captures the essence of the mellowing season, as cooler temperatures give way to a more serene atmosphere, perfect for leisurely strolls under the changing foliage.

Average September Wind Speed in Amersfoort

The chart displays monthly wind speed patterns in Amersfoort, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.34.44.33.94.13.03.43.93.2 m/s4.53.54.1
Data source: Amersfoort September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Amersfoort Compares to Other Months

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

In September, temperatures can range from a cool 3°C (38°F) at night to a warm 31°C (88°F) during the day, with an average of 15°C (59°F). The month brings around 70 mm (2.8 in) of precipitation over approximately 11 days, accompanied by relatively high humidity at 83%. In contrast, January is much colder, with temperatures dipping to a minimum of -8°C (17°F) and only reaching a maximum of 14°C (58°F), averaging around 4°C (40°F). The precipitation in January is slightly lower at 59 mm (2.3 in) but occurs over a similar number of days—12. The humidity is higher as well, at 88%. For a more detailed look at January conditions in Amersfoort, you can visit Amersfoort weather in January.

In comparing the weather between September and February, we see significant differences in temperature and overall climate conditions. September boasts a much warmer average temperature of 15°C (59°F), with highs reaching up to 31°C (88°F). In contrast, February experiences much colder temperatures, with an average of only 5°C (41°F) and lows dipping to -12°C (11°F). Both months receive similar amounts of precipitation, around 70-72 mm (2.8 in), but February has a slightly higher number of wet days at 12 compared to September's 11. Additionally, February's humidity of 88% is a tad higher than September's 83%, contributing to a chillier feel in the air. For more detailed insights, you can check Amersfoort weather in February.

In September, the weather features a more moderate temperature range with a minimum of 3°C (38°F), an average of 15°C (59°F), and a maximum of 31°C (88°F). The month experiences approximately 70 mm (2.8 in) of precipitation over 11 days, with a humidity level of 83%. In contrast, March is cooler, beginning with a minimum of -8°C (17°F) and reaching an average of 7°C (44°F) and a maximum of 22°C (71°F). Despite a similar level of precipitation at 74 mm (2.9 in), March has more rainy days, totaling 15, and a slightly higher humidity of 86%. For a more detailed look at the weather patterns during this month, check out Amersfoort weather in March.

September and April present notable contrasts in weather patterns. September tends to be warmer, with average temperatures ranging from a minimum of 3°C (38°F) to a maximum of 31°C (88°F), while April shows a cooler range, from -3°C (27°F) to a maximum of 27°C (82°F). Despite its warmer temperatures, September experiences more rainfall, accumulating about 70 mm (2.8 in) over approximately 11 days, compared to April's 42 mm (1.6 in) over 10 days. Humidity levels are fairly similar, with September at 83% and April slightly higher at 84%. For a deeper look into April weather in Amersfoort, you can refer to Amersfoort weather in April.

When comparing the weather in September and May, several notable differences emerge. September typically experiences higher maximum temperatures, reaching up to 31°C (88°F), while May sees similar highs, peaking at 31°C (89°F) but generally has lower average temperatures, with a maximum of 31°C (89°F) and an average of 13°C (56°F). Both months have a significant number of rainy days, with September averaging about 11 days and May slightly more at 13 days, but September receives a bit more precipitation overall at 70 mm (2.8 in) compared to May's 63 mm (2.5 in). Humidity levels are relatively high in both months, with September slightly more humid at 83% compared to May's 80%. For further details on May weather specifically, you can check Amersfoort weather in May.

In comparing the weather between September and June, we notice that June generally has milder temperatures, with average highs reaching 33°C (92°F) compared to September's maximum of 31°C (88°F). The minimum temperatures are also warmer in June, starting at 7°C (44°F) versus September's 3°C (38°F). Precipitation levels are relatively similar, with June receiving 73 mm (2.9 in) over 12 days and September slightly less at 70 mm (2.8 in) over 11 days. Furthermore, June experiences lower humidity at 75%, compared to September’s higher humidity of 83%. For more details on June weather in Amersfoort, you can visit Amersfoort weather in June.

When comparing the weather in September and July, notable differences emerge. September experiences a broader range of temperatures, with minimums dipping to 3°C (38°F) and maximums reaching up to 31°C (88°F), leading to an average of 15°C (59°F). In contrast, July is generally warmer, with minimum temperatures around 7°C (45°F) and maximums soaring to 39°C (103°F), averaging 18°C (65°F). Both months see significant precipitation, with July averaging 75 mm (3.0 in) over 13 days and September slightly lower at 70 mm (2.8 in) across 11 days. Additionally, September tends to be more humid at 83% compared to July’s 75%. For a more detailed understanding of July weather, you can refer to Amersfoort weather in July.

In comparing the weather between September and August, September experiences slightly cooler temperatures overall, with a minimum of 3°C (38°F) and an average of 15°C (59°F), compared to August’s minimum of 7°C (45°F) and an average of 18°C (66°F). While both months can see high temperatures, September's maximum reaches 31°C (88°F) versus August's peak of 34°C (94°F). Additionally, September has more precipitation days, with rainfall on 11 days totaling 70 mm (2.8 in), compared to August’s 15 days of rain with 87 mm (3.4 in). The humidity is also notably higher in September at 83%, while August maintains a more comfortable 75%. For a more detailed look at the weather patterns in August, you can visit Amersfoort weather in August.

In September, the weather is warmer, with temperatures ranging from a minimum of 3°C (38°F) to a maximum of 31°C (88°F), while October sees cooler conditions, with temperatures dipping to a minimum of 1°C (34°F) and peaking at 26°C (79°F). September has an average temperature of 15°C (59°F), compared to October's average of 12°C (54°F). Additionally, October experiences slightly more precipitation at 86 mm (3.4 in) over 14 days, versus September's 70 mm (2.8 in) over 11 days. Humidity also rises from 83% in September to 86% in October, making the latter month feel a bit more damp. For more detailed information, check out Amersfoort weather in October.

September and November present quite a contrast in weather patterns. In September, temperatures range from a minimum of 3°C (38°F) to a maximum of 31°C (88°F), making it a warm month with an average temperature of 15°C (59°F). The month typically sees 70 mm (2.8 in) of precipitation over 11 days, with humidity levels around 83%. In contrast, November brings cooler conditions, with temperatures dipping to a low of -3°C (27°F) and peaking at 19°C (66°F), resulting in a lower average of 7°C (45°F). Although November experiences less precipitation at 51 mm (2.0 in) over the same number of wet days, the humidity is slightly higher at 87%. For details on November's weather, check out Amersfoort weather in November.

September and December present stark contrasts in weather. In September, temperatures can range from a mild 3°C (38°F) at night to a warm 31°C (88°F) during the day, with an average of 15°C (59°F) and relatively low humidity at 83%. This month also sees about 70 mm (2.8 in) of precipitation over roughly 11 days, making it a month of shifting from summer warmth to the cooler fall climate. Conversely, December experiences much cooler temperatures, with averages dropping to 5°C (42°F) and a maximum of only 14°C (57°F), and dipping as low as -5°C (24°F) at night. It is characterized by higher precipitation totaling 87 mm (3.4 in) across 16 days, along with a slight increase in humidity to 86%. For more detailed insights on December weather, you can visit Amersfoort weather in December.

Compare Amersfoort's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Amersfoort

As September unfolds in Amersfoort, the weather begins to transition from the warmth of summer to the cooler embrace of autumn. Maximal temperatures can reach a pleasant 31°C (88°F), while the average drops to a more refreshing 15°C (59°F), marking a distinct shift from the intense heat of July and August. However, the month also brings a fair amount of precipitation, with rainfall occurring on 11 days, contributing to a higher humidity level of 83%. This blend of warmth and moisture creates a dynamic atmosphere, making September a unique time to experience the scenic beauty of Amersfoort. For a deeper dive into the region's weather patterns throughout the year, visit Amersfoort Climate.