September Weather in Lyon, France

Last updated: February 26, 2025

Lyon in September offers a delightful blend of summer warmth and early autumn chill. With maximum temperatures reaching 33°C (93°F), the city still basks in lingering summer heat, while the average temperature sits at a comfortable 18°C (64°F). As crisp evenings approach, temperatures can dip to a refreshing 4°C (40°F). Rainfall is moderate, totaling 65 mm (2.6 in) over approximately 8 days, contributing to the city's lush scenery. Humidity levels are around 72%, adding a touch of moisture to the air, making September a charming time to explore the beauty of Lyon.

September Temperature in Lyon

As September rolls into Lyon, the city experiences a delightful transition from the heat of summer to the crispness of autumn. With minimum temperatures around 4°C (40°F), and average highs reaching 33°C (93°F), the month offers a pleasant warmth ideal for outdoor exploration. The average temperature hovers at a comfortable 18°C (64°F), making it perfect for strolling through the vibrant streets or enjoying a meal at a terrace café. Compared to the sweltering summer months that precede it, September brings a welcome dip in temperatures, yet still maintains enough warmth to revel in the lingering sunshine, encapsulating the charm of early fall in Lyon.

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

The chart illustrates September temperature patterns in Lyon, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec384347536068727164554541
Data source: Temperature data for Lyon 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 Lyon

In September, Lyon experiences a mild transition into autumn, marked by an average precipitation of 65 mm (2.6 in) spread over 8 days. This slight decrease from the wetter summer months indicates a gradual reduction in rainfall as the city begins to prepare for the more substantial downpours of autumn and winter. Interestingly, September's precipitation is somewhat consistent with the patterns seen in August and July, aligning closely in both amount and frequency. As the leaves start to change, this month serves as a gentle reminder of the rainy season ahead, blending the remnants of summer with the crispness of fall.

September Precipitation Trends in Lyon

The chart displays monthly precipitation patterns in Lyon, 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.
JanFebMarAprMayJunJulAugSepOctNovDec66537051114848069659293116
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Lyon

As summer fades in Lyon, September marks a transition in humidity, dipping to 72%—a notable shift from the drier months of July and August, which experience lows of 68% and 61%, respectively. This resurgence in dampness hints at the approaching autumn, where humidity levels begin to climb once more, reaching 88% in October and peaking again at 91% by November. Overall, the data paints a picture of Lyon's climate, showing a gradual decline in humidity from the chilly start of the year, a noteworthy dip during the summer, and an inevitable rise as the seasons change, encapsulating the city's beautiful and dynamic weather patterns.

September Average Humidity in Lyon

This chart illustrates the average monthly humidity levels in Lyon, 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.
JanFebMarAprMayJunJulAugSepOctNovDec91%88%84%81%77%76%68%61%72%88%91%92%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Lyon

In September, Lyon experiences a decline in UV intensity, with the UV Index dropping to 6, categorizing it as high. This marks a noticeable transition from the intense summer months where indices reached their peak at 10 in June and 9 in July. With a burn time of 25 minutes, it's a crucial time for residents and visitors alike to remain mindful of sun exposure, especially following the very high levels seen in previous months. As autumn approaches, those enjoying the early fall sunshine should remember to protect their skin, as the warming rays can still pose a significant risk. For more detailed information on UV levels throughout the year, explore Lyon UV Index.

Maximum UV Index Levels in Lyon for September

The chart shows the monthly maximum UV Index (UVI) for Lyon 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.
JanFebMarAprMayJunJulAugSepOctNovDec2356810986532
Data source: Lyon 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 Lyon

As September arrives in Lyon, the city basks in 331 hours of glorious sunshine, a pleasant transition from the summer's peak. This month retains much of the warmth, reflecting a notable seasonal trend where sunlight gradually wanes from the summer highs of 419 hours in July. The gentle decline continues into autumn, yet September's hours still provide ample opportunity to explore the city's enchanting streets and vibrant culture before the cooler days ahead. With 16 hours less sunlight than in August, the days may be slightly shorter, but the charm of Lyon remains radiant as it welcomes the softer light of fall.

Monthly Sunshine Duration in Lyon: September Highlighted

The September sunshine duration represents the total number of hours Lyon 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.
JanFebMarAprMayJunJulAugSepOctNovDec148h229h296h351h366h412h419h393h331h276h214h188h
Data source: Lyon September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Lyon During September

In September, Lyon experiences a 45% chance of sunny weather, which positions it favorably among the late summer months. This likelihood is slightly lower than August’s 49%, indicating a gentle transition into autumn. As the year progresses from January’s mere 21% to the higher rates in spring and summer, September maintains a consistent sun probability, suggesting that while summer warmth begins to wane, the city still enjoys a fair amount of sunshine. This blend of lingering warmth and the onset of cooler days makes September an appealing time for outdoor activities amid the picturesque backdrop of Lyon.

Percentage of Sunny Days in September in Lyon

The chart illustrates the percentage of sunny days in Lyon 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 Lyon experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec21%41%55%54%36%43%40%49%45%44%27%27%
Data source: Lyon September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Lyon in September

As summer fades into autumn, September in Lyon, France offers a delightful transition with about 12 hours of daylight. This marks a noticeable shift from the peak summer months of June and July, which bask in 15 hours of sunlight. The gradual decrease in daylight reflects the onset of fall, as the city's vibrant greenery begins to blend with the warm hues of changing leaves. Following the long, sun-drenched days of summer, September retains a comfortable balance, outshining both October and November—with their shorter spans of 10 and 9 hours respectively. Overall, September serves as a gentle reminder of nature's cyclical rhythms, inviting residents and visitors alike to savor the lingering warmth before the days grow shorter.

Average Daylight Hours in Lyon for September

The chart illustrates the variation in daylight duration in Lyon throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 7m10h 22m11h 56m13h 33m14h 56m15h 38m15h 16m14h 2m12h 29m10h 52m9h 27m8h 43m
Data source: Lyon daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Lyon

As summer transitions to autumn in Lyon, the September winds whisper a gentle farewell, with an average speed of just 2.1 m/s (5 mph). This marks a noticeable decline from the slightly breezier spring months, where winds average around 3.3 m/s in April. The trend illustrates a cooling period as the city prepares for the crisper days ahead. Although summer’s warmth lingers, the soft breezes of September signal a shift, inviting residents and visitors to bask in the mellow charm of early fall. With each passing day, the air begins to carry the promise of autumnal adventures, blending tranquility with the vibrant energy that characterizes this beautiful city.

Average September Wind Speed in Lyon

The chart displays monthly wind speed patterns in Lyon, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.03.23.13.32.42.72.32.32.1 m/s3.02.42.2
Data source: Lyon September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Lyon Compares to Other Months

The weather in Lyon 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 Lyon and find detailed weather information for every month.

September and January exhibit stark contrasts in weather. In September, temperatures range from a mild 4°C (40°F) at night to a warm 33°C (93°F) during the day, with an average temperature of 18°C (64°F). The month sees approximately 65 mm (2.6 in) of precipitation over about 8 days, contributing to a moderately humid atmosphere at 72%. In stark contrast, January experiences much colder conditions, with temperatures dipping to a minimum of -8°C (17°F) and peaking at 15°C (60°F), averaging only 3°C (38°F). Precipitation remains similar at 66 mm (2.6 in) but occurs over more days—12 in total—resulting in higher humidity levels of 91%. For more detailed insights on winter weather, you can check Lyon weather in January.

When comparing the weather in September and February, distinct differences become apparent. September boasts a mild temperature range, with minimums of 4°C (40°F) and maximums reaching up to 33°C (93°F), along with an average of 18°C (64°F). The month typically experiences around 65 mm (2.6 in) of precipitation over 8 days and boasts a moderate humidity of 72%. In stark contrast, February presents a much cooler climate, with minimum temperatures plummeting to -9°C (16°F) and an average of only 6°C (43°F). Although slightly less precipitation at 53 mm (2.1 in) is recorded over 11 days, the humidity level rises significantly to 88%. For more information on February weather, you can check Lyon weather in February.

When comparing the weather in September and March, notable differences emerge. September typically enjoys a milder range of temperatures, with minimums around 4°C (40°F) and maximums reaching up to 33°C (93°F), while March experiences much cooler conditions, with lows plunging to -12°C (11°F) and highs capping at 23°C (74°F). Additionally, September has less precipitation, averaging 65 mm over about 8 days, compared to March's 70 mm over approximately 12 days, indicating a wetter month. The humidity also rises in March to 84%, higher than September's 72%, which can contribute to a chilly sensation despite the daytime warmth. For a detailed exploration of weather conditions during March, visit Lyon weather in March.

When comparing the weather in September and April, some notable differences emerge. September tends to be warmer overall, with average temperatures reaching 18°C (64°F) and maximums as high as 33°C (93°F), while April has a cooler average of 12°C (53°F) and a maximum of 28°C (82°F). Additionally, September experiences slightly more precipitation at 65 mm (2.6 in) over 8 days compared to April's 51 mm (2.0 in) also over the same number of days. Humidity levels are higher in April at 81%, compared to September's 72%, contributing to a different feel during these months. For a detailed look at conditions during this time, visit Lyon weather in April.

When comparing the weather in September and May, notable differences emerge in temperature and precipitation. September boasts a wider temperature range, with minimums around 4°C (40°F) and maximums reaching 33°C (93°F), resulting in an average of 18°C (64°F). In contrast, May starts cooler, with minimums at 0°C (33°F) and an average temperature of 15°C (60°F), peaking with a max of 32°C (89°F). Precipitation is significantly higher in May, totaling 113 mm (4.5 in) over 14 days, compared to September’s 65 mm (2.6 in) across 8 days. Humidity levels are slightly higher in May at 77%, compared to September’s 72%. For more detailed information, you can check out Lyon weather in May.

When comparing the weather in September and June, we can see notable differences in temperature and precipitation. September experiences a wider temperature range, with minimums around 4°C (40°F) and maximums peaking at 33°C (93°F), while June typically has milder nights starting at 8°C (46°F) and hotter days reaching up to 38°C (100°F). Precipitation is also more pronounced in June, with 84 mm (3.3 in) over approximately 12 days, compared to September’s 65 mm (2.6 in) spread over 8 days. Additionally, humidity levels are slightly higher in June at 76%, compared to September's 72%. For a more detailed look at the conditions during June, you can check out Lyon weather in June.

When comparing the weather in September to that of July, we can see some notable differences. September experiences a broader temperature range, with minimums dropping to 4°C (40°F) and maximums reaching up to 33°C (93°F), while July maintains a warmer average with minimums of 11°C (52°F) and maximums peaking at 39°C (102°F). In terms of precipitation, July tends to be slightly wetter with 80 mm (3.2 in) spread over 10 days, compared to September's 65 mm (2.6 in) over 8 days. Additionally, September's higher humidity at 72% contrasts with July's 68%, contributing to a more muggy feel later in the summer. For a detailed look at the weather conditions in July, visit Lyon weather in July.

September weather shows a notable shift from August, with average temperatures decreasing from 22°C (72°F) in August to 18°C (64°F) in September. The minimum temperatures in September dip to 4°C (40°F), compared to a milder 9°C (48°F) in August, while maximum temperatures also see a decline, peaking at 33°C (93°F) in September versus a hotter 39°C (103°F) in August. Precipitation levels are slightly similar, with September receiving 65 mm (2.6 in) over 8 days compared to August's 69 mm (2.7 in) across 9 days. Additionally, September has a higher humidity level of 72%, in contrast to August's 61%. For a detailed look at August weather, visit Lyon weather in August.

In September, the weather is characterized by warmer temperatures, with a minimum of 4°C (40°F) and an average high of 33°C (93°F), making it a more summer-like month. However, it experiences moderate humidity at 72% and precipitation of 65 mm (2.6 in) over about 8 days. In contrast, October brings a notable drop in temperatures, with a minimum of 1°C (33°F) and an average high of 26°C (80°F). This month is also wetter, with precipitation increasing to 92 mm (3.6 in) over 10 days and a higher humidity level of 88%. Those interested in the specific weather patterns of October can check Lyon weather in October for more details.

In September, the weather is generally warm with temperatures ranging from a minimum of 4°C (40°F) to a maximum of 33°C (93°F), averaging around 18°C (64°F). The month sees an average of 65 mm (2.6 in) of precipitation over approximately 8 days, accompanied by a humidity level of 72%. In contrast, November ushers in much cooler temperatures, with a minimum of -4°C (25°F), an average of 7°C (45°F), and a maximum of 20°C (69°F). Precipitation increases to 93 mm (3.7 in) over 13 days, and humidity rises significantly to 91%. For a closer look at what to expect during this month, check out Lyon weather in November.

In September, the weather in Lyon is generally warm and pleasant, with temperatures ranging from a minimum of 4°C (40°F) to a maximum of 33°C (93°F), and an average of 18°C (64°F). With a total precipitation of 65 mm (2.6 in) over about 8 days, September tends to be significantly drier and less humid, with an average humidity of 72%.

In contrast, December brings much cooler temperatures, with a minimum of -4°C (25°F) and a maximum of 16°C (62°F), averaged at only 5°C (42°F). This month sees nearly double the rainfall at 116 mm (4.6 in) over 17 days, and the humidity is much higher at 92%. For a detailed look at the winter weather conditions, you can check out Lyon weather in December.

Compare Lyon's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Lyon

As summer gracefully transitions into autumn, September in Lyon presents a delightful mix of warm temperatures and refreshing breezes. With average highs around 18°C, it feels pleasantly mild, especially compared to the sweltering heat of July and August. While occasional rain showers—totaling approximately 65 mm over about 8 days—add a splash of refreshment, the humidity remains noticeable, maintaining a cozy atmosphere. This month serves as a bridge, blending the vibrancy of summer while hinting at the calm of the coming fall. For more insights on seasonal variations, check out the Lyon Climate page.