September Weather in La Rochelle, France

Last updated: February 26, 2025

Experience the enchanting September weather in La Rochelle, France, where warm days meet refreshing breezes. With maximum temperatures reaching up to 30°C (87°F) and an average of 18°C (65°F), this coastal city offers a delightful climate for exploration and relaxation. Although the month sees a minimum temperature of 10°C (49°F), the 75% humidity keeps the air pleasantly invigorating. Visitors can expect about 44 mm (1.7 in) of precipitation over 9 days, ensuring that the surroundings remain lush and vibrant. Embrace the charm of September in La Rochelle, where the picturesque backdrop is matched by comfortably warm weather.

September Temperature in La Rochelle

As September unfolds in La Rochelle, the temperatures begin to soften, offering a delightful transition from the warmth of summer to the cooler embrace of autumn. With a minimum temperature of around 10°C (49°F), mornings and evenings carry a refreshing chill, while afternoons can still bask in pleasant warmth, peaking at 30°C (87°F). The average temperature sits comfortably at 18°C (65°F), making it an ideal time for outdoor exploration or leisurely coastal strolls. Notably, as the month progresses, one can observe a gradual dip in temperature compared to the summer months, yet the lingering warmth invites visitors to soak in the beauty of La Rochelle before the onset of deeper autumnal coolness. This charming mix of mild temperatures and vibrant scenery perfectly encapsulates the essence of early fall in this coastal gem.

September Weather in La Rochelle: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in La Rochelle, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec454750556066696865595148
Data source: Temperature data for La Rochelle generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in La Rochelle

September in La Rochelle marks a transition in precipitation patterns as summer gives way to autumn. With an average of 44 mm (1.7 inches) of rain over 9 days, it sits comfortably in the middle of the year’s rainfall totals. This month follows a notably dry summer, where July and August received only 29 mm (1.1 in) and 33 mm (1.3 in) respectively, highlighting a significant uptick in moisture as temperatures begin to cool. As the city braces for the wetter months ahead, September’s rainfall foreshadows the impending increase, particularly as October and November are among the year's wettest, with 85 mm (3.4 in) and 94 mm (3.7 in) respectively. This shift hints at the unique rhythm of La Rochelle’s climate, where dry spells yield to nurturing rains, paving the way for the lush landscapes of autumn.

September Precipitation Trends in La Rochelle

The chart displays monthly precipitation patterns in La Rochelle, 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.
JanFebMarAprMayJunJulAugSepOctNovDec6269764269742933448594121
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in La Rochelle

September in La Rochelle marks a subtle transition in humidity, settling at 75%. This figure reflects a slight uptick from the drier summer months of 65% in July and 67% in August, suggesting a gradual return of moisture as autumn approaches. The month serves as a bridge between the warm, more arid conditions of summer and the increasingly humid atmosphere typical of fall, where humidity rises significantly to 85% in October and peaks in the winter months. The overall trend indicates that while September's humidity is more temperate, it hints at the onset of the wetter, cooler seasons ahead, enriching the coastal charm of La Rochelle.

September Average Humidity in La Rochelle

This chart illustrates the average monthly humidity levels in La Rochelle, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec88%87%84%83%81%75%65%67%75%85%88%90%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in La Rochelle

As summer wanes in La Rochelle, September brings a shift in the UV Index, settling at a moderate level of 6. This marks a noticeable decline from the intense very high ratings of 8 and 9 recorded in July and August, yet it still calls for caution as the sun continues to deliver a powerful punch. With a burn time of 25 minutes, those enjoying outdoor activities should remain vigilant to protect their skin. This transitional month showcases the trend of decreasing UV levels, encouraging a balance between sun-soaked days and protective measures. For an in-depth look at UV trends throughout the year, explore more at La Rochelle UV Index.

Maximum UV Index Levels in La Rochelle for September

The chart shows the monthly maximum UV Index (UVI) for La Rochelle 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.
JanFebMarAprMayJunJulAugSepOctNovDec235689986532
Data source: La Rochelle 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 La Rochelle

In September, La Rochelle basks in a delightful 340 hours of sunshine, marking a charming transition from the summer glow. This month often reflects a dip from the sun-drenched peaks of July and June, where hours soared above 400, yet it remains radiant compared to the earlier months of the year. The steady increase in daylight from January's mere 153 hours to September's warmth highlights a magnificent journey towards the fall. As summer's vibrancy gracefully wanes, visitors can still relish the lingering sunshine, making September a splendid time to explore the coastal beauty of this charming French city.

Monthly Sunshine Duration in La Rochelle: September Highlighted

The September sunshine duration represents the total number of hours La Rochelle 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.
JanFebMarAprMayJunJulAugSepOctNovDec153h214h298h347h398h407h422h397h340h284h234h195h
Data source: La Rochelle September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in La Rochelle During September

As summer transitions to autumn, La Rochelle experiences a notable change in its weather patterns, particularly in September. With a 50% chance of sunny days, this month sees a comforting balance, making it a favorable time for outdoor activities amid the lingering warmth. This probability is consistent with the sunniest months of August and aligns closely with the favorable conditions of October. Throughout the year, the likelihood of sunshine tends to peak in the spring and early summer, but as September arrives, travelers can still expect ample opportunities to bask in the pleasant temperatures before the chill of autumn sets in. Overall, while the sunshine may begin to wane, La Rochelle remains inviting, with September offering a delightful mix of sun and early fall charm.

Percentage of Sunny Days in September in La Rochelle

The chart illustrates the percentage of sunny days in La Rochelle 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 La Rochelle experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec21%32%52%59%39%46%48%54%50%52%40%38%
Data source: La Rochelle September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in La Rochelle in September

As September rolls into La Rochelle, the days begin to shorten, offering a transitional glimpse between the long summer days and the emerging autumn chill. With around 12 hours of daylight, this month marks a gentle decline from the peak brightness of summer, where June and July basked in 15 hours of sunlight. September balances warmth and light, wrapping the city in a comfortable glow as it prepares for the cooler months ahead. As the year progresses, daylight decreases steadily, culminating in the 8 hours of light seen in December, but for now, there’s still ample time to enjoy La Rochelle’s coastal beauty.

Average Daylight Hours in La Rochelle for September

The chart illustrates the variation in daylight duration in La Rochelle throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 4m10h 20m11h 56m13h 34m14h 59m15h 41m15h 18m14h 4m12h 29m10h 51m9h 25m8h 40m
Data source: La Rochelle daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in La Rochelle

As September ushers in the arrival of autumn in La Rochelle, France, the wind begins to mellow, settling into an average speed of 3.8 m/s (8 mph). This marks a notable decline from the breezier summer months of June, July, and August, when wind speeds hovered around 4.4 to 4.5 m/s (10 mph). Interestingly, this gentle shift in the September breeze initiates a consistent trend toward calmer conditions leading into the fall, contrasting sharply with the more vigorous gusts of winter that return in December. Overall, September's soft winds create a serene atmosphere, perfect for leisurely strolls along the picturesque coastline, as nature prepares for the seasonal transition.

Average September Wind Speed in La Rochelle

The chart displays monthly wind speed patterns in La Rochelle, 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.
JanFebMarAprMayJunJulAugSepOctNovDec5.55.44.64.55.53.54.54.43.8 m/s4.44.45.5
Data source: La Rochelle September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in La Rochelle Compares to Other Months

The weather in La Rochelle 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 La Rochelle and find detailed weather information for every month.

In September, the weather is generally warmer, with temperatures ranging from a mild 10°C (49°F) to a maximum of 30°C (87°F) and an average of 18°C (65°F). The humidity sits at 75%, and despite experiencing some rain over 9 days, total precipitation is relatively low at 44 mm (1.7 in). In contrast, January brings much cooler temperatures, with a minimum of -4°C (25°F) and a maximum of 15°C (60°F), averaging around 7°C (45°F). The humidity rises to 88%, and while the precipitation increases to 61 mm (2.4 in) over 10 days, the overall atmosphere feels far chillier. For a more detailed look at what January has to offer, you can check out La Rochelle weather in January.

September and February showcase distinct weather profiles, reflecting the transition from summer to winter. In September, temperatures range from a minimum of 10°C (49°F) to a comfortable average of 18°C (65°F), peaking at 30°C (87°F). The month experiences relatively lower humidity at 75% and sees about 44 mm (1.7 in) of precipitation over 9 days. In contrast, February offers a chillier climate, with temperatures dipping as low as -5°C (24°F) and averaging around 9°C (48°F). The maximum temperature reaches 19°C (66°F), while humidity is higher at 87%. February is wetter too, receiving 69 mm (2.7 in) of precipitation across 11 days. For more details on February weather, you can explore La Rochelle weather in February.

In comparing the weather of September and March, it’s evident that these months present contrasting climates. September tends to be warmer, with average temperatures ranging from a cool 10°C (49°F) at night to a pleasant 30°C (87°F) during the day, while enjoying relatively lower humidity at 75%. In contrast, March sees much cooler temperatures, with averages from -5°C (23°F) to a maximum of 22°C (72°F), and a higher humidity level of 84%. Additionally, March is wetter, receiving 75 mm (3.0 in) of precipitation over 12 days compared to September's 44 mm (1.7 in) over just 9 days. For a more detailed look at March conditions, check out La Rochelle weather in March.

When comparing the weather between September and April, notable differences emerge in temperature and humidity. September offers milder nights with a minimum temperature of 10°C (49°F) and warmer days averaging 18°C (65°F), peaking at 30°C (87°F). In contrast, April experiences cooler conditions, with nights dipping to 1°C (34°F) and a comfortable average of 13°C (55°F), reaching up to 24°C (76°F) during the day. Precipitation levels are similar, with September seeing 44 mm (1.7 in) over 9 days and April slightly less at 42 mm (1.7 in) over 8 days, although April has higher humidity at 83% compared to September's 75%. For more detailed insights on April weather, you can visit La Rochelle weather in April.

When comparing the weather in September and May, notable differences can be observed. September tends to be warmer, with average temperatures reaching 18°C (65°F) and maximums of 30°C (87°F), while May's temperatures are slightly cooler, with an average of 16°C (60°F) and maximums of 29°C (84°F). Precipitation is higher in May, totaling 69 mm (2.7 in) over 11 days, compared to September's 44 mm (1.7 in) over 9 days. Additionally, humidity levels are slightly higher in May at 81%, versus 75% in September. For more detailed insights into May weather specifically, you can refer to La Rochelle weather in May.

When comparing the weather in September and June, both months exhibit mild temperatures, with September showing an average of 18°C (65°F) and June slightly warmer at 19°C (66°F). The maximum temperatures in September can reach up to 30°C (87°F), while June can peak at 33°C (92°F), indicating that June provides a bit more heat overall. In terms of precipitation, June receives 74 mm (2.9 in) over about 10 days, compared to September's 44 mm (1.7 in) over 9 days, making June generally wetter. Interestingly, both months maintain the same humidity level of 75%, suggesting a similarly muggy feel despite the differences in temperature and rainfall. For a more detailed look at June weather, you can visit La Rochelle weather in June.

In comparing the weather between September and July, September tends to be cooler and more variable. The minimum temperature drops to 10°C (49°F), while the average temperature is 18°C (65°F), with a maximum reaching 30°C (87°F). In contrast, July enjoys slightly warmer temperatures, with a minimum of 13°C (55°F), an average of 21°C (70°F), and a high of 33°C (91°F). Additionally, September experiences more rainfall with 44 mm (1.7 in) over about 9 days, compared to July's 29 mm (1.1 in) spread over just 6 days. Humidity levels also differ, with September at 75% compared to July's 65%. For more detailed information, check out La Rochelle weather in July.

In comparing the weather between August and September, we see a noticeable shift in temperatures and humidity. August tends to be warmer, with a minimum of 12°C (55°F) and an average of 20°C (69°F), peaking at 33°C (92°F). In contrast, September experiences cooler conditions, with a minimum of 10°C (49°F) and an average of 18°C (65°F), reaching a maximum of 30°C (87°F). Additionally, September receives slightly more precipitation at 44 mm (1.7 in) over 9 days, compared to August's 33 mm (1.3 in) over 7 days. Moreover, the humidity is higher in September at 75%, compared to 67% in August. For a more detailed look at August weather, check out La Rochelle weather in August.

The transition from September to October brings noticeable changes in weather patterns. In September, temperatures range from a minimum of 10°C (49°F) to a maximum of 30°C (87°F), with an average of 18°C (65°F). The month has relatively mild weather with 44 mm (1.7 in) of precipitation over about 9 days, alongside a humidity level of 75%. By contrast, October experiences cooler temperatures, with minimums dropping to 4°C (40°F) and an average of 15°C (59°F), peaking at 24°C (75°F). Rainfall increases significantly to 85 mm (3.4 in) across 12 days, and humidity rises to 85%. For more detailed weather information, you can check La Rochelle weather in October.

September and November present a stark contrast in weather conditions. In September, temperatures range from a mild 10°C (49°F) at night to a warm 30°C (87°F) during the day, with an average of 18°C (65°F). The month sees some rainfall, with about 44 mm (1.7 in) of precipitation over 9 days, and humidity levels are relatively moderate at 75%. In contrast, November brings cooler weather, with temperatures dipping to a minimum of 1°C (35°F) and an average temperature of only 10°C (51°F). The maximum temperature reaches 20°C (67°F) but is accompanied by a significant increase in precipitation, totaling 94 mm (3.7 in) over 12 days, and higher humidity at 88%. For more details about the weather in this month, you can refer to La Rochelle weather in November.

September offers a much warmer climate compared to December, with average temperatures reaching 18°C (65°F), peaking at a comfortable 30°C (87°F). The month experiences relatively low precipitation, with 44 mm (1.7 in) falling over just 9 days, and humidity levels sitting at 75%. In contrast, December brings a significant drop in temperatures, averaging around 9°C (48°F) and only maxing out at 16°C (60°F). Rainfall increases in December to 121 mm (4.8 in) over 16 days, accompanied by higher humidity at 90%. For a detailed look at the weather in December, visit La Rochelle weather in December.

Compare La Rochelle's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in La Rochelle

September in La Rochelle offers a delightful transition from summer to autumn, with pleasantly warm days and cooler evenings. Unlike the sweltering heat of July and August, this month strikes a balance, inviting visitors to enjoy the vibrant coastal scenery without the excessive humidity. While you might face some rain on about a third of the days, it’s mostly gentle, allowing for plenty of sunny moments. As you explore the charming streets, keep in mind that the average temperature is a comfortable 18°C, making September an ideal time for outdoor adventures. For a comprehensive look at the weather trends throughout the year, visit La Rochelle Climate.