Last updated: August 27, 2025
In September, Alkmaar, Netherlands, experiences a delightful transition into autumn with temperatures ranging from a maximum of 25°C (78°F) to a comfortable average of 16°C (61°F), dipping to a mild minimum of 9°C (49°F). While the month brings a moderate precipitation total of 92 mm (3.6 in) across approximately 12 days, the high humidity level of 83% adds a unique charm to the early fall atmosphere. This blend of mild temperatures and variable weather invites both locals and visitors to enjoy the picturesque landscapes and vibrant city life, making September a captivating time to explore Alkmaar.
In September, Alkmaar experiences a delightful transition from the warmth of summer to the crispness of autumn. With temperatures ranging from a minimum of 9°C (49°F) to a comfortable maximum of 25°C (78°F), the month showcases an average of 16°C (61°F), making it an ideal time for outdoor activities and exploration. This gentle drop in temperatures from August highlights the onset of fall, yet still retains enough warmth for pleasant days. Expect a refreshing blend of mild days and cooler evenings, perfect for enjoying the city’s vibrant festivals and charming canals as nature begins to showcase its autumn colors.
In September, Alkmaar experiences a substantial 92 mm (3.6 in) of rain, marking it as one of the wetter months of the year. This increase in precipitation follows the already significant rainfall in August, which saw 94 mm (3.7 in), creating a trend of elevated moisture as summer transitions into autumn. With about 12 days of rainfall, September maintains a balance between wet days and intermittent dry spells, which is characteristic of early fall. This month, along with October, typically heralds the onset of the rainier season, setting the stage for the approaching winter when precipitation climbs even higher. As the landscape shifts, the cool, damp air replaces summer warmth, highlighting the changing seasons in this charming Dutch city.
In September, Alkmaar experiences a subtle shift in humidity, with levels averaging 83%, slightly higher than the preceding months of summer. This uptick reflects a gradual transition as the warm, dry air of August gives way to the cooler, wetter conditions of autumn. Interestingly, September's humidity acts as a bridge, positioning itself between the late summer low of 78% and the higher levels that dominate once more in October, when humidity returns to 86%. Overall, the trends indicate a consistent pattern where humidity remains relatively high throughout the year, with only minor fluctuations, particularly in the summer months. This creates a uniquely refreshing atmosphere for both residents and visitors alike.
In September, the UV Index in Alkmaar, Netherlands, settles at a moderate level of 5, allowing for a more balanced outdoor experience as summer gives way to autumn. With a recommended burn time of 30 minutes, it's a great opportunity for residents and visitors to enjoy the mild weather without the extreme sun intensity of July and August, which boasted a very high index of 8. This gradual decrease in UV exposure mirrors the transition from the summer's high index of 7 in August to the cooler months ahead. As October approaches, the index will dip further to 3, emphasizing the importance of monitoring UV levels as the seasons change. For a complete overview of UV conditions throughout the year, visit Alkmaar UV Index.
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As summer gracefully bows out, September in Alkmaar showcases a beautiful transition, offering 330 hours of sunlight. This month highlights a notable decrease from the sun-soaked days of July, which boasted an impressive 426 hours, yet still radiates warmth compared to the looming gloom of autumn. Following the vibrant warmth of summer, September provides a soothing balance, hinting at the 297-hour decline by October. Despite this ebbing light, the lingering brightness of autumn ensures that the charm of Alkmaar remains vibrant, inviting both locals and visitors to bask in its gentle, sunlit glow before the days grow shorter.
In September, the likelihood of sunny weather in Alkmaar, Netherlands, sits at 31%. While this represents a slight dip from the peak sunshine chances seen in the early summer months of June and July, it still offers a pleasant shift from the gloomier autumn months ahead. With the sun gracing the skies more frequently in the spring and summer, September holds onto some of that warmth, making it a cherished time for outdoor activities before the chill of fall truly sets in. As you plan your September outings, you can look forward to relatively favorable conditions, though be prepared for a mix as the season transitions.
As September arrives in Alkmaar, daylight begins its gradual decline from the lush brightness of summer. With 12 hours of daylight, this month marks a transition from the sunny abundance of August, which enjoyed a peak of 14 hours. The fading light hints at the approaching autumn, as days shorten in line with the trend observed throughout the year. Following the lengthy days of June and July, where daylight danced for a remarkable 16 hours, September's more modest daylight fosters a gentle shift in rhythm. As the year progresses into October, daylight will further wane to 10 hours, heralding a cozy embrace of the darker evenings.
As September unfolds in Alkmaar, the breeze begins to soften, bringing with it an average wind speed of 4.8 m/s (11 mph). This marks a notable decline from the heights of summer, where wind speeds peaked at 5.9 m/s (13 mph) in August. Transitioning from the warm months, September sets the stage for the upcoming autumn, with wind dynamics hinting at the brisker conditions to follow in October, which sees a jump to 7.1 m/s (16 mph). The overall trend reveals a gradual decrease in wind speed as summer wanes, making way for a subtle shift in the atmosphere, as the charm of the season starts to give way to the invigorating gales of fall.
Weather in Alkmaar varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Alkmaar, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present strikingly different weather patterns. In September, temperatures range from a mild 9°C (49°F) at night to a warm 25°C (78°F) during the day, offering an average of 16°C (61°F). This month experiences 92 mm (3.6 in) of precipitation over about 12 days, with humidity levels at 83%. In contrast, January is much colder, with temperatures dipping to a minimum of -3°C (27°F) and a maximum of just 12°C (53°F), averaging around 5°C (42°F). The precipitation is lower at 62 mm (2.4 in), spread over 13 days, and humidity rises slightly to 87%. For a detailed look at January weather, visit Alkmaar weather in January.
In comparing the weather of September and February, notable differences emerge. September typically sees a milder climate with minimum temperatures around 9°C (49°F) and maximums reaching 25°C (78°F), resulting in an average temperature of 16°C (61°F). This month experiences about 92 mm (3.6 in) of rainfall over 12 days, with humidity levels at 83%. In contrast, February brings a much colder atmosphere, with minimum temperatures dropping to -6°C (21°F) and a maximum of 14°C (58°F), averaging just 5°C (42°F). Precipitation is lower at 71 mm (2.8 in), but it still falls on 12 days, accompanied by a slightly higher humidity of 87%. For a more detailed look at the February weather, check out Alkmaar weather in February.
In September, the weather is notably warmer, with average temperatures around 16°C (61°F) and highs reaching up to 25°C (78°F), making it an enjoyable month for outdoor activities. In contrast, March experiences much cooler conditions, with average temperatures of 6°C (44°F) and maximums only hitting 15°C (60°F). While both months see a fair amount of rainfall, September has slightly more precipitation at 92 mm (3.6 in) compared to March's 67 mm (2.6 in). Additionally, humidity levels are similar, with September at 83% and March slightly higher at 86%. For more detailed information, check out Alkmaar weather in March.
When comparing the weather in September and April, it is clear that September tends to be warmer and wetter. In September, temperatures range from a minimum of 9°C (49°F) to a maximum of 25°C (78°F), with an average of 16°C (61°F) and a notable precipitation level of 92 mm (3.6 in) over 12 days. In contrast, April shows a cooler climate, with temperatures ranging from 2°C (36°F) to 23°C (74°F), and an average of only 9°C (48°F). Additionally, April experiences significantly less rainfall, with 37 mm (1.5 in) across 8 days. Humidity levels remain relatively high in both months, with September at 83% and April at 85%. For more detailed information, visit Alkmaar weather in April.
In comparing the weather of September and May, September tends to be warmer overall with an average temperature of 16°C (61°F) and a maximum of 25°C (78°F), while May has a cooler average of 12°C (54°F) and a maximum of 26°C (79°F). September experiences more precipitation, totaling 92 mm (3.6 in) spread over 12 days, compared to May's 44 mm (1.7 in) over 9 days. Humidity levels are slightly higher in September at 83%, whereas May sits at 84%. For more detailed insights on May weather, you can check Alkmaar weather in May.
In September, the weather is characterized by a temperature range with a minimum of 9°C (49°F) and a maximum of 25°C (78°F), leading to an average of 16°C (61°F). This month experiences relatively high humidity at 83% and a notable amount of rainfall, with 92 mm (3.6 in) over 12 days. In contrast, June offers slightly warmer conditions, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 29°C (84°F), maintaining the same average of 16°C (61°F). June also sees less precipitation at 66 mm (2.6 in) over 10 days and slightly lower humidity at 81%. For more detailed insights into June weather, you can check out Alkmaar weather in June.
When comparing the weather in September and July, notable differences emerge. September experiences cooler temperatures, with an average of 16°C (61°F) compared to July's warmer average of 18°C (64°F). Additionally, July sees higher maximum temperatures, reaching up to 30°C (87°F), while September peaks at 25°C (78°F). Precipitation is more abundant in September, totaling 92 mm (3.6 in) over 12 days, compared to July's 69 mm (2.7 in) over 13 days. Humidity is slightly higher in September at 83%, while July maintains a humidity level of 80%. For more detailed insights into July's weather, you can visit Alkmaar weather in July.
September brings a noticeable shift in weather compared to August. The average temperature drops from 18°C (65°F) in August to 16°C (61°F) in September, with the maximum temperature also decreasing, from 29°C (84°F) to 25°C (78°F). While both months experience similar levels of precipitation, with September receiving 92 mm (3.6 in) over 12 days and August seeing 94 mm (3.7 in) over 15 days, the humidity is slightly higher in September at 83% compared to August's 78%. For more details on weather patterns in August, you can visit Alkmaar weather in August.
In September, the weather is generally milder with average temperatures ranging from a minimum of 9°C (49°F) to a maximum of 25°C (78°F), while October sees a drop in temperatures, with a range from 5°C (41°F) to a maximum of 23°C (73°F). Precipitation also increases in October, totaling 117 mm (4.6 in) over 17 days compared to September's 92 mm (3.6 in) over 12 days, resulting in a slightly wetter month. Additionally, humidity levels rise from 83% in September to 86% in October, contributing to a more damp atmosphere. For more details on October's weather in Alkmaar, visit Alkmaar weather in October.
In September, the weather is generally milder, with temperatures ranging from a minimum of 9°C (49°F) to a maximum of 25°C (78°F) and an average of 16°C (61°F). The month experiences about 92 mm (3.6 in) of precipitation over 12 days, making it a relatively wet period, but with lower humidity at 83%. In contrast, November brings cooler temperatures, with a minimum of just 1°C (35°F) and a maximum of 17°C (62°F), averaging around 9°C (48°F). Although the total precipitation decreases to 68 mm (2.7 in), it is spread over more days, with rainfall occurring on 15 days and a slightly higher humidity of 87%. For a detailed overview of precipitation and temperatures, check Alkmaar weather in November.
In September, the weather is relatively mild, with average temperatures ranging from a minimum of 9°C (49°F) to a maximum of 25°C (78°F). This month typically sees around 92 mm (3.6 in) of precipitation spread over approximately 12 days, and the humidity levels hover around 83%. In contrast, December brings a much chillier climate, featuring average temperatures that dip to a minimum of -2°C (28°F) and peak at only 12°C (54°F). With an increased likelihood of rain, December records about 106 mm (4.2 in) of precipitation over 18 days, accompanied by higher humidity levels at 86%. For a closer look at the weather specifics in December, visit Alkmaar weather in December.
As September arrives in Alkmaar, the weather presents a refreshing transition from the warm summer months to the cooler embrace of autumn. With a maximum temperature that gently peaks at around 25°C, the days still offer pleasant moments, although the average temperature settles down to a comfortable 16°C. This month introduces a noticeable increase in humidity, averaging 83%, along with an uptick in precipitation, bringing a total of 92 mm over about 12 days. This shift marks a distinct difference from the drier, hotter summer, as nature prepares itself for the coming season. For a deeper understanding of how September fits into the wider climate patterns, explore the detailed insights at Alkmaar Climate.