Last updated: March 24, 2025
In September, Courmayeur, Italy, offers a fascinating blend of early autumn chill and moderate warmth, with temperatures ranging from a maximum of 20°C (68°F) to a minimum of -9°C (16°F). The average temperature settles around 8°C (47°F), providing a crisp backdrop for outdoor adventures. Visitors can expect about 70 mm (2.7 in) of rainfall over 13 days, contributing to the lush scenery of the region. With an average humidity of 73%, the air is imbued with a refreshing dampness that enhances the beauty of the surrounding mountains, making September an enchanting time to explore Courmayeur's breathtaking landscapes.
As September unfolds in Courmayeur, Italy, the summer warmth begins to wane, giving way to the crisp embrace of autumn. With temperatures ranging from a minimum of -9°C (16°F) to a maximum of 20°C (68°F), this month offers a mild average of 8°C (47°F), marking a notable transition from the sweltering summer months. The cool evenings and mornings invite cozy sweaters and the vibrant colors of changing foliage awaken the splendid beauty of the Alps. As nature prepares for winter, September serves as a picturesque bridge, blending the remnants of summer's charm with the tranquil beauty of autumn. This foliage-rich time is perfect for outdoor activities, ensuring visitors enjoy both comfortable days and cooler nights in this enchanting alpine retreat.
September in Courmayeur, Italy, marks a subtle shift in precipitation as summer transitions into autumn. With an average rainfall of 70 mm (2.7 in) spread across 13 days, the month experiences a notable decrease in both the amount and frequency of rain compared to the wetter months of spring and early summer. This dip aligns with a broader trend observed from the peak precipitation of May, which sees an increase to 154 mm (6.1 in), and gradually tapers off into the dryer months ahead. As the leaves begin to change and temperatures cool, this gentle moderation in rainfall sets the stage for the approaching autumn, offering a picturesque backdrop for locals and visitors alike.
As summer fades into autumn, September in Courmayeur greets visitors with a comfortable humidity level of 73%. This marks a noticeable shift from the peak summer months, where humidity dipped to an enjoyable 63% in August. The gradual increase in moisture levels signals the approach of fall, yet maintains a balance that prevents the air from feeling too heavy. Compared to the 91% humidity of January, September offers a refreshing reprieve, bridging the gap between the drier summer and the wetter months ahead. As the year progresses, humidity will climb again, reaching 89% by October, illustrating Courmayeur's characteristic climate variability throughout the seasons.
As summer transitions into autumn, September in Courmayeur, Italy experiences a notable shift in the UV Index, registering a value of 8, which falls under the very high exposure category. This means that even as the days grow shorter, the sun's rays remain potent, with a burn time of just 15 minutes for unprotected skin. The UV Index in September is slightly lower than the peak in July and August, yet it still necessitates caution, particularly for those planning outdoor activities. The trend indicates that while the intensity of UV radiation diminishes from the blistering summer heights, it remains significant enough to warrant protection. To better prepare for your visit, you can find detailed insights at Courmayeur UV Index.
UV Risk Categories
September in Courmayeur, Italy, offers a delightful transition into autumn, with 329 hours of sunshine—a significant dip from the sun-drenched peak of 423 hours in July, but still radiant compared to the grayer winter months ahead. This month marks a gradual descent in daylight, reflecting the patterns of preceding months where sunshine gradually increased from a modest 176 hours in January to a summer high in July. As summer's warmth lingers into September, visitors can still relish the stunning scenery bathed in sunlight, while also anticipating the crisp, clear days that October promises with its 289 hours. Overall, September embodies a serene blend of lingering warmth and the first hints of fall, perfect for outdoor exploration in the breathtaking alpine landscape.
As summer draws to a close, September in Courmayeur, Italy, presents a tapestry of weather where the sun graces the region with a 28% chance of shining. This figure reflects a slight dip from the more abundant sunshine seen in August, which enjoys a 42% likelihood. Interestingly, September's sun chances trend closer to the lower probabilities observed in late spring, which are often marked by transitional weather patterns. However, with October's return to 43%, the subsequent month shows promise for more sunny days, suggesting that the mesmerizing beauty of the Alps can still be savored under clear skies even as summer bids farewell.
As summer gently fades into autumn, September in Courmayeur, Italy offers a delightful transition, where daylight lasts approximately 12 hours. After basking in the 15 hours of sunlight during the peak months of June and July, the daylight gradually diminishes, creating a cozy atmosphere as the days become noticeably shorter. This decrease signals the approach of cooler temperatures, mirroring the reduction from 14 hours in August. The rhythm of the seasons is palpable, with each month transitioning gracefully, from 14 hours of light in May to the crisp 10 hours seen by October. September's mild days still invite exploration, making it a perfect time to enjoy the stunning autumn foliage against the backdrop of the magnificent Alps.
As summer gracefully gives way to autumn, September's gentle breeze in Courmayeur, Italy, tends to be the calmest of the year, with an average wind speed of just 1.0 m/s (2 mph). This subtle shift in wind patterns signifies a transition from the warmer months, where winds slightly pick up in July and August at 1.2 to 1.3 m/s. Notably, throughout the year, the wind tends to hover around 1.3 m/s, showing a consistent, soothing presence that complements the stunning Alpine landscape. As we approach the chill of October, the winds pick up again, reminding us of nature’s rhythmic cycles and the serene beauty that Courmayeur offers in every season.
The weather in Courmayeur 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 Courmayeur and find detailed weather information for every month.
September and January present starkly different weather conditions. In September, temperatures range from a minimum of -9°C (16°F) to a maximum of 20°C (68°F), with an average of 8°C (47°F). The month experiences about 70 mm (2.7 in) of precipitation over 13 days, accompanied by a relative humidity of 73%. In contrast, January is much colder, with temperatures plunging to a minimum of -25°C (-14°F) and a maximum of only 5°C (42°F), averaging at -9°C (15°F). Precipitation increases to 139 mm (5.5 in) over 10 days, and humidity rises to 91%, making it feel even colder. For those looking to understand January's weather further, check out Courmayeur weather in January.
In September, the weather offers a milder range, with temperatures fluctuating from a minimum of -9°C (16°F) to a pleasant average of 8°C (47°F) and a maximum of 20°C (68°F). This month experiences lower humidity at 73% and about 70 mm (2.7 in) of precipitation over approximately 13 days. In contrast, February is significantly colder, with temperatures dipping to a minimum of -22°C (-7°F) and averaging around -6°C (22°F), reaching a maximum of only 8°C (46°F). This month also sees higher humidity at 87% and more precipitation, totaling 99 mm (3.9 in) over 11 days. For more detailed insights into the chilly February weather, you can check Courmayeur weather in February.
In September, the weather tends to be milder, with temperatures ranging from a chilly minimum of -9°C (16°F) to a pleasant maximum of 20°C (68°F), averaging around 8°C (47°F). The month experiences about 70 mm (2.7 inches) of precipitation over 13 days, accompanied by a humidity level of 73%. In contrast, March is significantly colder, with temperatures plummeting to a minimum of -25°C (-13°F) and averaging -4°C (26°F), peaking at 11°C (51°F). Precipitation in March is higher at 127 mm (5.0 inches) over 15 days, along with increased humidity of 84%. For further details on March weather specifics, visit Courmayeur weather in March.
When comparing the weather in September and April, notable differences emerge in temperature and humidity. September enjoys milder temperatures, with an average of 8°C (47°F) and highs reaching up to 20°C (68°F), while April's average temperature is significantly lower at 0°C (33°F), peaking at just 13°C (55°F). Additionally, April tends to be wetter, with similar precipitation levels—70 mm (2.8 in)—but over fewer days (10 compared to September's 13), and it also has a higher humidity level of 83% versus September's 73%. For more detailed insights, you can explore Courmayeur weather in April.
In comparing the weather between September and May, September generally offers milder temperatures, with a minimum of -9°C (16°F) and an average of 8°C (47°F), reaching a maximum of 20°C (68°F). In contrast, May experiences cooler temperatures, ranging from a minimum of -14°C (7°F) to an average of 4°C (40°F), with a similar maximum of 19°C (66°F). While both months see significant precipitation, September has about 70 mm (2.7 in) over 13 days, whereas May receives a much higher total of 154 mm (6.1 in) across 20 days. Humidity levels are also slightly elevated in May at 78%, compared to September's 73%. For more detailed insights about May weather, visit Courmayeur weather in May.
In comparing the weather between September and June, we observe notable differences in temperature and precipitation. September experiences a wider temperature range, with minimums dropping to -9°C (16°F) and maximums reaching up to 20°C (68°F), resulting in a cooler average of 8°C (47°F). In contrast, June offers milder conditions, with temperatures ranging from a minimum of -3°C (27°F) to a maximum of 25°C (78°F), providing a more pleasant average of 10°C (50°F). Regarding precipitation, June is wetter, with 105 mm (4.1 in) falling over 17 days, compared to September's 70 mm (2.7 in) distributed across 13 days. Humidity levels are relatively similar in both months, hovering around 73% in September and 75% in June. For more detailed weather insights, you can explore Courmayeur weather in June.
When comparing the weather in September and July, notable differences emerge in both temperature and precipitation. July tends to be warmer, with average temperatures ranging from a minimum of 0°C (33°F) to a maximum of 26°C (78°F), while September experiences cooler temperatures, averaging between -9°C (16°F) and 20°C (68°F). Additionally, July sees higher precipitation levels at 102 mm (4.0 in) over 16 days, compared to September's 70 mm (2.7 in) over 13 days. Humidity levels remain quite similar, with September slightly higher at 73% compared to July's 72%. For more detailed insights, you can check Courmayeur weather in July.
In comparing the weather of September and August, September tends to be cooler, with temperatures ranging from a minimum of -9°C (16°F) to a maximum of 20°C (68°F) and an average of 8°C (47°F). This is a notable drop from August, where temperatures ranged from a minimum of 0°C (33°F) to a maximum of 24°C (75°F) and an average of 12°C (54°F). Additionally, September experiences more precipitation, totaling 70 mm (2.7 in) over 13 days, compared to August's 100 mm (4.0 in) over 14 days. While September has a higher humidity level at 73%, August is slightly drier with 63% humidity. For a more detailed look at the August climate, you can check Courmayeur weather in August.
September and October present a notable shift in weather conditions. In September, temperatures range from a minimum of -9°C (16°F) to a maximum of 20°C (68°F), with an average temperature of 8°C (47°F). The month experiences around 70 mm (2.7 in) of precipitation over 13 days, accompanied by a relative humidity of 73%. In contrast, October brings cooler temperatures, with a minimum of -8°C (17°F) and a maximum of 16°C (60°F), averaging 4°C (39°F). This month is wetter, recording 111 mm (4.4 in) of precipitation over 12 days, and the humidity increases significantly to 89%. For more detailed information, you can check Courmayeur weather in October.
In September, temperatures are milder, ranging from a minimum of -9°C (16°F) to a maximum of 20°C (68°F), with an average of 8°C (47°F). The month experiences about 70 mm (2.7 in) of precipitation over 13 days and boasts a humidity level of 73%. In contrast, November brings much colder conditions, with temperatures dropping significantly, where the minimum reaches -23°C (-9°F) and the average is -3°C (27°F), peaking at 12°C (55°F). This month sees increased precipitation of 106 mm (4.2 in) over 14 days, coupled with higher humidity at 90%. For more details on the weather in November, you can check out Courmayeur weather in November.
September and December present stark contrasts in weather conditions. In September, temperatures range from a minimum of -9°C (16°F) to a maximum of 20°C (68°F), with an average of 8°C (47°F); the month sees about 70 mm (2.7 in) of precipitation over 13 days, accompanied by a humidity level of 73%. By December, the climate shifts dramatically, with temperatures plunging to a minimum of -22°C (-7°F) and a maximum of only 4°C (40°F), averaging -8°C (19°F). Moreover, December experiences significantly higher precipitation, totaling 216 mm (8.5 in) over 17 days, and humidity rises to 90%. For those interested in more details, you can check out the Courmayeur weather in December.
As September arrives in Courmayeur, the weather begins to shift, offering a unique blend of summer's warmth and autumn's chill. With temperatures often reaching a pleasant 20°C (68°F) during the day but dipping to a brisk 8°C (47°F) at night, this month stands out for its notable temperature swings. Unlike the dryer summer months, September sees increased precipitation, with around 70 mm (2.7 in) of rain over approximately 13 days, contributing to a humidity level of 73%. This transition creates a picturesque atmosphere, ideal for those looking to explore the stunning landscapes as they start to change colors. For more detailed insights on what to expect throughout the year, visit Courmayeur Climate.