Last updated: February 26, 2025
Aachen's weather in September offers a dynamic blend of seasonal shifts, with temperatures ranging from a minimum of 2°C (36°F) to a maximum of 32°C (91°F), showcasing the transition from summer warmth to the coolness of autumn. The average temperature settles at a comfortable 15°C (59°F), inviting outdoor exploration. With 64 mm (2.5 in) of precipitation spread over 10 days, occasional rain refreshes the scenery, while an average humidity of 81% adds a touch of moisture to the air. As the month progresses, visitors can experience the charming nuances of Aachen's late summer and early autumn climate.
In September, Aachen experiences a delightful transition as summer gently fades into autumn. The temperatures during this month showcase a noticeable shift, with minimums hovering around 2°C (36°F) and averages reaching a comfortable 15°C (59°F). The warmth lingers, peaking at 32°C (91°F), reminiscent of the late summer heat, yet the crispness of early fall starts to emerge. This balance of warmth and coolness presents an ideal opportunity for exploring the city's rich history and beautiful landscapes, making September a particularly inviting time for both locals and visitors. As the month progresses, one can sense the promise of autumn, with cooler evenings hinting at the seasonal changes ahead.
In September, Aachen experiences moderate precipitation, receiving an average of 64 mm (2.5 in) over about 10 days. This marks a noticeable dip compared to the heavier rainfall seen in the summer months, particularly July, which boasts the highest total at 94 mm (3.7 in). The shift to autumn begins to manifest, as rain tends to fall more sporadically, leading to a gradual decline in both total precipitation and rainy days. While September's weather is generally more stable compared to the oppressive summer downpours, it still retains a refreshing charm, hinting at the transition toward the wetter, cooler months ahead.
September in Aachen, Germany, marks a noticeable transition in humidity levels as summer gives way to autumn. With humidity at 81%, it remains relatively high compared to the drier months of June, July, and August, where levels dipped to 74%, 72%, and 71%, respectively. This slight increase signals the onset of a more humid period as the year progresses. Interestingly, the trend reveals that humidity rebounds sharply towards the end of the year, climbing back up to 88% in October and peaking at 92% in December. Thus, September provides a bridge between the warm, drier summer months and the wetter autumn season, making it a unique time for those in Aachen to experience a blend of lingering warmth and increasing moisture in the air.
In September, Aachen experiences a moderate UV Index of 5, indicating a shift towards milder sun exposure as summer wanes. With a burn time of 30 minutes, it's essential to take precautions, especially during the sun's peak hours. This marks a notable decrease from the very high levels recorded in June and July, where the UV Index peaked at 8, necessitating more stringent sun protection. As fall approaches, the UV Index steadily drops from the high levels of May and August, reflecting the changing seasons. Whether you're enjoying a leisurely stroll or engaging in outdoor activities, stay informed about the UV Index in Aachen to safeguard your skin. For more detailed insights, check out Aachen UV Index.
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As summer fades and autumn begins, September in Aachen still basks in an impressive 316 hours of sunshine, making it one of the sunniest months of the year. Following a peak in July with 408 hours, September marks a gentle decline, yet the light remains abundant compared to the dreariness of winter, where hours dip to just 133 in December. The transition from summer’s peak radiance to the colors of fall is seamlessly mirrored in the daylight, with September offering a robust balance for outdoor enthusiasts. As the leaves start to change, Aachen's golden light provides the perfect backdrop for leisurely strolls, capturing the last whispers of summer before the clouds of winter settle in.
In Aachen, Germany, September offers a notable increase in the likelihood of sunny weather, with a 38% chance of sunshine. This month stands out as a shift towards more favorable conditions compared to the earlier summer months of July and August, which hover around 32%. While still lower than the spring months—notably March and April with chances as high as 40% and 41%—September retains its charm as autumn begins to unfold. As the year progresses into October, the likelihood drops to 29%, emphasizing September's status as a sweet spot for enjoying warmer days before the colder months set in.
As the summer sun begins its retreat in Aachen, September witnesses a gentle transition, offering about 12 hours of daylight. This month marks a noticeable shift from the sun-drenched days of July and August, where daylight peaked at 15 and 14 hours, respectively. However, September still retains a certain warmth, bridging the gap between the longer days of summer and the shorter, cozy hours of autumn. Following this pattern, October will further reduce daylight to 10 hours, hinting at the approaching winter. The gradual loss of daylight reflects nature's rhythm, inviting residents to savor the remaining bright afternoons while anticipating the serene beauty of the shorter days ahead.
In September, Aachen experiences a gentle whisper of wind, with an average speed of 2.8 m/s (6 mph), marking a notable dip following the summer months. This trend continues a pattern seen throughout the year, where the wind tends to soften as the seasons shift. After the higher speeds in May and June, the breeziness gradually wanes, suggesting a calmness that prepares the city for the cooler autumnal days ahead. The transition into fall comes with a reflective stillness in the air, creating an inviting atmosphere for leisurely strolls amid the historical charm of Aachen, as nature begins to don its vibrant autumn hues.
The weather in Aachen changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Aachen and find detailed weather information for every month.
September and January present striking contrasts in weather patterns. September boasts a wider temperature range, with minimums around 2°C (36°F) and maximums soaring to 32°C (91°F), yielding an average of 15°C (59°F). During this month, precipitation totals about 64 mm (2.5 in) over approximately 10 days, coupled with a relatively high humidity of 81%. In stark contrast, January experiences much colder temperatures, with lows dropping to -8°C (17°F) and an average of just 3°C (37°F). Precipitation is slightly higher at 79 mm (3.1 in), occurring over 14 days, and humidity is also elevated at 91%. For more details on January weather, you can check Aachen weather in January.
In comparing the weather between September and February, one can notice significant differences in both temperature and precipitation patterns. September typically enjoys a mild average temperature of 15°C (59°F), with highs reaching up to 32°C (91°F), making it feel quite warm despite some cooler nights. In contrast, February presents a much colder climate, featuring an average temperature of just 5°C (40°F) and minimums dipping as low as -10°C (14°F).
Moreover, September experiences 64 mm (2.5 in) of precipitation spread over approximately 10 days, while February sees slightly higher rainfall at 78 mm (3.1 in) across about 12 days, contributing to a noticeably humid environment with 90% humidity. For more detailed information on February weather, you can check out Aachen weather in February.
In comparing the weather between September and March, significant differences emerge in temperature and precipitation patterns. September experiences a much warmer range with minimum temperatures around 2°C (36°F) and highs reaching up to 32°C (91°F), while March is notably cooler, with minimum temperatures dropping to -10°C (14°F) and average highs of only 23°C (73°F). Precipitation is slightly less in September, totaling 64 mm (2.5 in) over about 10 days, compared to March's 87 mm (3.4 in) spread over 15 days, indicating that March is not only wetter but also frequently cloudier with higher humidity levels at 87% compared to September's 81%. For a more detailed look at March's weather specifics, check out Aachen weather in March.
In comparing the weather of September and April, we can observe notable differences. September features a wider temperature range with minimums around 2°C (36°F) and maximums reaching up to 32°C (91°F), resulting in a comfortable average temperature of 15°C (59°F). In contrast, April typically experiences cooler conditions with a minimum of -3°C (26°F) and an average of 9°C (49°F), peaking at 27°C (81°F). Both months see precipitation on about 10 days, but September tends to be wetter with 64 mm (2.5 in) compared to April's 40 mm (1.6 in). Interestingly, while humidity levels are somewhat similar, September's 81% is slightly lower than April's 84%. For more detailed information on weather trends, you can visit Aachen weather in April.
In comparing the weather of September and May, we see distinct differences in both temperature and precipitation. September experiences a wider temperature range, with minimums reaching 2°C (36°F) and maximums climbing to 32°C (91°F), averaging around 15°C (59°F). In contrast, May typically has slightly cooler temperatures, with a minimum of 0°C (32°F) and a maximum that peaks at 31°C (89°F), averaging 13°C (56°F).
When it comes to precipitation, September sees about 64 mm (2.5 in) over approximately 10 days, whereas May has slightly more rainfall at 74 mm (2.9 in) spread over 13 days. Humidity levels are also noteworthy, with September at 81% and May slightly lower at 77%. For a more in-depth look at May's climate, check out Aachen weather in May.
In comparing the weather of September and June, we can observe distinct differences in temperature and precipitation patterns. September experiences a wider range of temperatures, with a minimum of 2°C (36°F) and a maximum of 32°C (91°F), while June has milder minimum temperatures at 7°C (44°F) but reaches a similar maximum of 33°C (92°F). Overall, June tends to be warmer on average, at 18°C (64°F) compared to September's 15°C (59°F). Precipitation is also notable, with September receiving 64 mm (2.5 in) over 10 days, while June has a higher total of 88 mm (3.4 in) across 12 days. Additionally, September's humidity is slightly higher at 81% compared to June's 74%. For more detailed insights, you can check Aachen weather in June.
When comparing the weather in September and July, several notable differences emerge. September experiences a wider temperature range, with minimums dipping to 2°C (36°F) and maximums reaching 32°C (91°F), while July tends to be warmer overall, with minimum temperatures around 8°C (46°F) and maximums soaring to 40°C (104°F). Precipitation is higher in July, with 94 mm (3.7 in) over 13 days, compared to September’s 64 mm (2.5 in) across 10 days, though September's humidity is higher at 81% versus July’s 72%. For more specifics on July weather patterns, you can refer to Aachen weather in July.
In September, temperatures drop significantly compared to August, with a minimum of 2°C (36°F) and an average of 15°C (59°F), whereas August boasts a minimum of 7°C (45°F) and an average of 19°C (66°F). The maximum temperatures in September reach up to 32°C (91°F), slightly lower than August's peak of 35°C (96°F). Rainfall also differs, with September experiencing 64 mm (2.5 in) of precipitation over 10 days, while August records 78 mm (3.1 in) across 16 days. Additionally, September has a higher humidity level at 81%, compared to August's 71%. For more details on August weather patterns, check Aachen weather in August.
In September, temperatures in the region range from a minimum of 2°C (36°F) to a maximum of 32°C (91°F), with an average of 15°C (59°F). The month experiences about 64 mm (2.5 in) of precipitation across 10 days, accompanied by a humidity level of 81%. By contrast, October sees cooler weather, with temperatures dropping to a minimum of 1°C (34°F) and peaking at 25°C (78°F), averaging 11°C (53°F). Precipitation increases slightly to 82 mm (3.2 in) over 14 days and humidity rises to 88%. For more detailed information, you can check Aachen weather in October.
September and November present quite distinct weather characteristics. In September, temperatures range from a minimum of 2°C (36°F) to a warm maximum of 32°C (91°F), with an average of 15°C (59°F). This month sees about 64 mm (2.5 in) of precipitation over approximately 10 days, and the humidity hovers around 81%. In contrast, November experiences much cooler temperatures, with a minimum of -5°C (24°F) and a maximum of 18°C (66°F), averaging only 7°C (44°F). The precipitation slightly decreases to 59 mm (2.3 in) but occurs over more days, totaling 11. The humidity also rises to 91%, creating a chillier and more damp atmosphere. For more details on November's conditions, you can visit Aachen weather in November.
September and December exhibit striking differences in weather patterns. In September, temperatures range from a mild 2°C (36°F) at night to a warm 32°C (91°F) during the day, making it a month characterized by warmth and occasional rain, with an average of 15°C (59°F) and 64 mm (2.5 in) of precipitation over about 10 days. Conversely, December brings colder conditions, with minimum temperatures dropping to -5°C (24°F) and a maximum of only 15°C (59°F), resulting in an average temperature of 5°C (41°F). This month experiences higher precipitation levels of 112 mm (4.4 in) spread over 20 days, along with increased humidity at 92%. For a detailed look at weather specifics, check out Aachen weather in December.
As summer bids farewell, September in Aachen introduces a notable transition in weather patterns compared to earlier months. The days begin with a hint of warmth, where occasional peaks can reach a warm 32°C, but overall, the average temperature settles around a mild 15°C, creating a pleasant atmosphere for outdoor activities. This month also marks an uptick in humidity at 81%, leading to a refreshing crispness in the air, particularly during cooler mornings and evenings. Rainfall is more prevalent with about 64 mm spread over 10 days, which adds vitality to the lush greenery of the region. For those curious about what to expect year-round, visit Aachen Climate for more details.