Last updated: February 26, 2025
September in Rennes, France offers a delightful blend of warm days and cooler evenings, with maximum temperatures peaking at 32°C (90°F) and an average of 16°C (62°F). As summer fades, the crisp air can dip as low as 5°C (41°F) during the night, inviting a cozy atmosphere. Although the month experiences a moderate precipitation level of 55 mm (2.2 in) spread over 9 rainy days, the overall humidity sits at a manageable 75%. This weather showcases the beauty of transitioning seasons, making September an ideal time to explore the vibrant charm of Rennes.
September in Rennes, France, marks a delightful transition into autumn, with temperatures exhibiting a pleasant range. The month features minimums around 5°C (41°F), providing a brisk, refreshing start to fall, while average temperatures rise to 16°C (62°F), allowing for comfortable outdoor activities. On warmer days, the maximum temperature can reach up to 32°C (90°F), reminiscent of summer's lingering warmth. This gradual shift in temperatures signifies a move away from the intense heat of July and August, as the city begins to embrace cooler evenings and the first hints of autumn foliage. Overall, September offers a balanced climate, ideal for enjoying the vibrant cultural scene and the stunning natural surroundings of Rennes.
September in Rennes, France, brings a moderate precipitation amount of 55 mm (2.2 in), typically spread over nine days throughout the month. This rainfall is slightly higher than the summer months of July and August, which averaged around 50 mm and 53 mm respectively, indicating a gentle transition into the wetter autumn season. Though September's precipitation is less than October's anticipated 88 mm, it serves as a prelude to the increasingly frequent rainy days ahead, setting the stage for the cozy, leaf-strewn streets of Rennes. As autumn approaches, the weather subtly shifts, with September acting as a bridge between the hot summer and the cool, rainier months to follow.
As summer transitions into autumn in Rennes, France, September experiences a modest drop in humidity to 75%, a noticeable shift from the peak summer months. This level reflects a move away from the more oppressive summer heat, where humidity dipped to 65% in July and rose slightly to 67% in August. While September maintains a comfortable balance, it serves as a prelude to the increasing humidity levels typical of fall and winter, which see an upward trend, culminating in 90% by December. This gradual evolution highlights the dynamic nature of Rennes' climate, where humidity ebbs and flows with the seasons, offering a refreshingly crisp atmosphere that invites exploration.
As summer fades into autumn, September in Rennes, France experiences a notable shift in its UV Index, dropping to 6, signaling a high exposure category with a burn time of 25 minutes. This decline from the intense UV levels of the preceding months—where July and August sported a UV Index of 9—illustrates the transition toward cooler seasons, while still highlighting the need for sun protection during peak hours. With a moderate index trend observed from April through August, September maintains a significant UV presence. As you enjoy the early fall sunshine, be mindful of your skin's sensitivity and stay informed with details at Rennes UV Index.
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As summer gracefully transitions into autumn, September in Rennes still basks in a generous 324 hours of sunshine. This marks a continuation of the year's increasing daylight, peaking in July with 414 hours before gradually tapering off in the fall. The vibrant sunlight in September creates a warm and inviting atmosphere, perfect for savoring the last days of outdoor activities. This month’s sunshine stands in contrast to the winter months, where daylight dips significantly—only 135 hours in January and 185 hours in December. Overall, September embodies a sweet farewell to summer, bridging the gap between the bright, sun-drenched days and the cooler, cozy months ahead.
When it comes to September in Rennes, France, the likelihood of sunny weather stands at 42%, marking a notable improvement from the earlier summer months. This figure reflects a gradual rise from March's 48%, peaking in April with 56%, before a slight decline during the peak of summer. Interestingly, while September doesn't reach summer highs, it remains favorable compared to the early months of the year, where chances of sunshine barely surpassed 20%. As the autumn season approaches, the weather in Rennes can still provide delightful sunny days, making this month a wonderful time for outdoor activities before the cooler temperatures arrive.
As summer fades into autumn, September in Rennes brings a gentle reduction in daylight, averaging around 12 hours. This month marks a transition from the longest days of June and July, where sunlight persists for an impressive 15 hours, to the shorter days of late autumn. The daylight gradually diminishes from the vibrant 15 hours of May and the lingering warmth of August's 14 hours. September serves as a bridge, allowing residents to enjoy the last remnants of outdoor activities before the daylight shrinks further to 10 hours by October. This subtle shift not only highlights the seasonal changes but also encourages a slower pace of life, as the cooler months approach and the days grow shorter once again.
As summer gives way to autumn in Rennes, France, the September winds begin to whisper a gentle farewell, with an average wind speed of just 3.0 m/s (7 mph). This marks a noticeable dip following the slightly breezier months of May and June, where the winds reached peaks of 4.3 m/s (10 mph) and 2.7 m/s (6 mph) respectively. The cooler air in September signifies a transition, hinting at the briskness to come in October, which sees a slight uptick back to 3.6 m/s (8 mph). Overall, September's serene wind patterns reflect the calm before the storm, as nature prepares for the vibrant changes of autumn, inviting residents and visitors alike to enjoy the tranquil landscapes that this charming city has to offer.
The weather in Rennes 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 Rennes and find detailed weather information for every month.
September and January present markedly different weather patterns. In September, temperatures range from a minimum of 5°C (41°F) to a maximum of 32°C (90°F), with an average of 16°C (62°F), making it a warmer month overall. The precipitation measures 55 mm (2.2 in) spread over 9 days, and humidity hovers around 75%. In contrast, January experiences much cooler temperatures, with a minimum of -7°C (19°F) and an average of 6°C (43°F), peaking at 16°C (60°F). Precipitation is slightly lower at 46 mm (1.8 in), also occurring over 9 days, but the humidity increases to 88%, giving it a more pronounced chill. For more detailed information on January weather, visit Rennes weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a cool minimum of 5°C (41°F) to a warm maximum of 32°C (90°F), with an average of 16°C (62°F). The month sees about 55 mm (2.2 in) of precipitation over 9 days and maintains a humidity level of 75%. In stark contrast, February experiences colder temperatures, with a minimum of -6°C (22°F) and a maximum of 21°C (69°F), averaging 7°C (45°F). It has slightly more precipitation at 60 mm (2.3 in) over 11 days and higher humidity at 87%. For more details on weather conditions during this time, visit Rennes weather in February.
In September, the weather generally features a wider temperature range, with daytime highs reaching up to 32°C (90°F) and an average of 16°C (62°F). The month experiences about 55 mm (2.2 in) of precipitation over approximately 9 days, coupled with a humidity level of 75%. In contrast, March has cooler temperatures, with a maximum of 24°C (75°F) and an average of 9°C (48°F), yet it can drop as low as -7°C (20°F) at night. March sees slightly more rainfall, totaling 58 mm (2.3 in) across around 12 days, and a higher humidity level of 84%. For more details on March’s climate, check out Rennes weather in March.
When comparing the weather in September and April, notable differences emerge in temperature and precipitation patterns. September experiences warmer temperatures, with averages reaching 16°C (62°F) and maximums of 32°C (90°F), while April sees lower averages of 11°C (52°F) and maximums of 26°C (80°F). Both months have a similar number of rainy days, with rainfall measuring 55 mm (2.2 in) in September and 48 mm (1.9 in) in April. Interestingly, humidity levels remain relatively high in both months, with September at 75% and April slightly higher at 83%. For a more detailed look at April’s climate, visit Rennes weather in April.
September and May both present mild temperatures, but with distinct differences in their overall conditions. In September, the minimum temperature is slightly warmer at 5°C (41°F), while the average temperature is a bit higher at 16°C (62°F), peaking at a maximum of 32°C (90°F). This month experiences about 55 mm (2.2 in) of precipitation over 9 days, with humidity levels around 75%.
In contrast, May starts with cooler mornings, with a minimum of 0°C (32°F) and an average temperature of 14°C (58°F). It sees a maximum temperature of 30°C (86°F) and slightly higher precipitation at 67 mm (2.6 in) spread over 11 days, along with increased humidity at 81%. For more specific insights into the weather patterns in May, you can visit Rennes weather in May.
In comparing the weather between September and June, we see some notable differences. September generally has a wider temperature range, with minimums around 5°C (41°F) and maximums reaching up to 32°C (90°F), leading to an average temperature of 16°C (62°F). In contrast, June offers slightly warmer temperatures, with minimums of 6°C (44°F) and maximums hitting 35°C (95°F), averaging 18°C (64°F).
Precipitation also varies between the two months; September experiences about 55 mm (2.2 in) of rain over 9 days, while June sees higher rainfall at 100 mm (3.9 in) across 11 days. Despite the differences in temperature and precipitation, both months share a consistent humidity level of 75%.
For a detailed look at June's weather, you can visit Rennes weather in June.
When comparing the weather in September and July, we see distinct variations in temperature and humidity. September experiences a lower minimum temperature of 5°C (41°F) and an average temperature of 16°C (62°F), while July has a minimum temperature of 7°C (46°F) and an average of 19°C (67°F). Notably, July boasts a higher maximum temperature, reaching up to 37°C (99°F), compared to September’s peak of 32°C (90°F). In terms of precipitation, September receives slightly more rain at 55 mm (2.2 in) over 9 days, while July has around 50 mm (2.0 in) over 8 days. Additionally, September's humidity level is higher at 75%, compared to July's 65%. For detailed insights, you can check the Rennes weather in July.
In comparing the weather of September to that of August, we see a notable shift in temperature and humidity. September experiences a broader temperature range, with a minimum of 5°C (41°F), an average of 16°C (62°F), and a maximum of 32°C (90°F), compared to August's milder range of 7°C (46°F) minimum, 19°C (66°F) average, and 35°C (96°F) maximum. While August has slightly less precipitation at 53 mm (2.1 in) over 8 days compared to September's 55 mm (2.2 in) over 9 days, the humidity rises in September to 75%, suggesting a more humid atmosphere than August's 67%. For more detailed insights, you can check Rennes weather in August.
September typically offers warmer temperatures, with averages around 16°C (62°F) and highs reaching up to 32°C (90°F), making it a pleasant month before the chill of autumn sets in. In contrast, October experiences a noticeable drop, with average temperatures hovering around 13°C (55°F) and maximums peaking at 24°C (76°F). Additionally, October sees an increase in precipitation, totaling 88 mm (3.5 in) over 11 days, compared to September's 55 mm (2.2 in) over 9 days. The humidity also rises in October to 85%, suggesting a more damp and chilly atmosphere. For more details, check out Rennes weather in October.
In September, the weather tends to be quite warm, with temperatures ranging from a minimum of 5°C (41°F) to a maximum of 32°C (90°F), and an average temperature of 16°C (62°F). The month sees around 55 mm (2.2 in) of precipitation over 9 days, with humidity levels around 75%. In contrast, November brings a much cooler climate, with temperatures dropping to a minimum of -1°C (30°F), an average of 8°C (48°F), and a maximum of 17°C (64°F). Precipitation increases to 71 mm (2.8 in) over 11 days, coupled with higher humidity at 88%. This shift highlights the transition from the warmer, sunnier days of September to the crisp and damp conditions typical of late autumn. For more detailed information, you can check Rennes weather in November.
In September, the weather tends to be warmer with temperatures ranging from a minimum of 5°C (41°F) to a max of 32°C (90°F), resulting in a pleasant average of 16°C (62°F). In contrast, December brings much cooler temperatures, with a minimum of -3°C (26°F) and a maximum of only 16°C (60°F), leading to an average of 7°C (46°F). Additionally, September experiences moderate precipitation of 55 mm (2.2 in) over about 9 days, while December sees increased rainfall, totaling 97 mm (3.8 in) over approximately 15 days. The humidity also rises in December, reaching 90% compared to 75% in September. For more details, check out Rennes weather in December.
As September transitions Rennes into the autumn season, it brings a welcome balance of warmth and crispness. With maximum temperatures peaking around 32°C (90°F), this month stands out from the cooler summer months, while still averaging a comfortable 16°C (62°F). Rain is a gentle presence, falling about 9 days throughout the month, adding up to 55 mm (2.2 in), which is less than in the summer but still enough to keep the lush surroundings vibrant. The humidity remains relatively high at 75%, offering a distinct freshness in the air. This blend of warmth and moisture makes September a unique time to experience the charm of Rennes. For more detailed insights, check out Rennes Climate.