Last updated: March 24, 2025
In September, Aosta, Italy, experiences a diverse range of weather patterns, making it an intriguing time to visit. With maximum temperatures reaching around 20°C (68°F) and an average temperature of 8°C (47°F), the month offers a pleasant climate for outdoor activities. However, visitors should be prepared for cooler evenings, as minimum temperatures can drop to -7°C (20°F). Rainfall is common, with 64 mm (2.5 in) of precipitation spread over approximately 14 days, contributing to a humidity level of 73%. This combination of conditions creates a unique, crisp atmosphere, perfect for enjoying the beautiful autumn foliage in the picturesque Alpine scenery.
In September, Aosta begins to transition from the warmth of summer into the cooler embrace of autumn. Temperatures range from a brisk -7°C (20°F) at night to a pleasant 20°C (68°F) during the day, with an average hovering around 8°C (47°F). This shift marks a significant drop compared to the late summer months, yet the crisp air also brings a refreshing charm to the region. As the mountains start donning their fall colors, September invites visitors to enjoy both the lingering warmth of daytime sun and the cool serenity of cooler evenings, making it an ideal time for outdoor adventures and exploring the stunning landscapes of the Aosta Valley.
In September, Aosta, Italy, experiences a noticeable dip in precipitation, averaging 64 mm (2.5 inches) over 14 days. This decline marks a transition from the wetter summer months, such as May with 144 mm, to a more moderate fall climate. The trend highlights a shift towards drier weather as autumn approaches, creating a tranquil atmosphere perfect for exploring the region's stunning landscapes. With the cooler temperatures and reduced rainfall, September is an ideal time for outdoor activities, as the mountains begin to don their early autumn hues against a backdrop of crisp, clear skies.
As summer transitions into autumn, September brings a noticeable shift in humidity levels in Aosta, Italy, settling at a comfortable 73%. This marks a slight increase from the drier August, where humidity dropped to a refreshing 63%. Following the dry summer months, the return of higher humidity in September signals the approach of cooler temperatures, reminiscent of the wetter conditions experienced in the preceding months of winter. The trend is clear: while the air remains relatively mild, the humidity begins to rise again, hinting at the onset of a more humid season ahead as October looms with its higher 89% mark.
As September arrives in Aosta, Italy, the UV Index remains noteworthy, measuring 8, which falls into the very high exposure category. This signifies that sun protection is essential during outdoor activities, with a burn time of just 15 minutes. While the summer months of June and July showcased an extreme UV Index of 11, the gradual decline in September reflects a transition into the cooler autumn season. Despite this drop, it is crucial for residents and visitors alike to remain vigilant against sun exposure. For those interested in tracking UV levels, detailed information can be found at Aosta UV Index.
UV Risk Categories
As September rolls into Aosta, Italy, the region basks in 329 hours of glorious sunshine, a slight dip from the sun-drenched heights of July and August. This month marks a transition, where the lingering warmth of summer begins to blend with the cooler whispers of autumn. After basking in 424 hours of sunshine in July, Aosta experiences a gradual decrease, yet the late summer rays still provide a vibrant backdrop for twilight strolls and scenic views. The trend is evident: sunshine hours peak in the peak summer months before gracefully declining through October and winter. Nonetheless, September still boasts more sunlight than early winter, reminding visitors of the lasting allure of Aosta's skies.
In Aosta, Italy, September offers a modest 27% chance of sunny weather, marking a decline from the warmer summer months of August, which boasts a more hopeful 47%. Following the peak of summer, the weather begins to transition, showcasing a trend where the likelihood of sunshine drops as the region heads into the cooler autumn months. This pattern suggests that while the days are still pleasant, potential outdoor activities may be more unpredictable as September progresses, reminding visitors to embrace the fleeting warmth before the much cooler October arrives, with its improved 43% sunny chance.
As summer fades into autumn, September in Aosta, Italy, welcomes a gentle transition with 12 hours of daylight. Following the peak of summer, where daylight stretches to a lengthy 15 hours in June and July, September brings a gradual decrease. This shift signifies the onset of fall, with daylight hours receding to 14 hours in August before dipping further. The pattern seen throughout the year highlights a distinct rhythm: shorter days in the colder months of winter, starting at 9 hours in January and descending to an even shorter 8 hours by December. This annual cycle not only reflects Aosta's geographical position but also captivates residents and visitors alike, offering a visual reminder of the comforting predictability of nature.
As summer gives way to autumn, September in Aosta, Italy, brings a gentle transition in wind patterns, with an average wind speed of just 1.0 m/s (2 mph)—the calmest of the year. This noticeable drop from the summer months is part of a broader trend, where wind speeds tend to peak in the colder months. The mild breezes of September create a serene atmosphere, perfect for leisurely strolls through the city or along the picturesque countryside. With each passing week, the air becomes crisper, hinting at the beauty of the changing seasons ahead, while the soft winds whisper tales of summer's end.
The weather in Aosta 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 Aosta and find detailed weather information for every month.
In September, temperatures range significantly from a chilly -7°C (20°F) at night to a mild 20°C (68°F) during the day, with an average temperature of 8°C (47°F). The month sees about 64 mm (2.5 in) of precipitation over approximately 14 days, with a relative humidity of 73%. In contrast, January experiences much colder conditions, with minimum temperatures dropping to -25°C (-13°F) and an average of -9°C (16°F), while daytime highs only reach up to 4°C (39°F). Additionally, January is wetter, with precipitation totaling 114 mm (4.5 in) over roughly 10 days and a higher humidity level at 91%. For more detailed information, check out Aosta weather in January.
In comparing the weather of September and February, notable differences emerge. September boasts a milder temperature range, with minimums around -7°C (20°F) and a comfortable average of 8°C (47°F), peaking at 20°C (68°F). This month experiences a total precipitation of 64 mm (2.5 in) over approximately 14 days, paired with a humidity level of 73%. In contrast, February is significantly colder, with minimum temperatures plunging to -22°C (-7°F) and an average temperature of -6°C (22°F), only reaching a maximum of 8°C (47°F). This winter month has higher precipitation levels at 79 mm (3.1 in) across 12 days, along with increased humidity at 87%. For more detailed insights, check out Aosta weather in February.
When comparing the weather in September and March, it's clear that March tends to be much colder. In September, temperatures range from a minimum of -7°C (20°F) to a pleasant average of 8°C (47°F), peaking at 20°C (68°F). In contrast, March showcases significantly lower temperatures, with a minimum of -25°C (-13°F) and an average of -4°C (25°F), only reaching a maximum of 10°C (50°F). Additionally, March experiences heavier precipitation, with 106 mm (4.2 in) over 15 days, compared to September's 64 mm (2.5 in) over 14 days. The humidity is also higher in March at 84%, compared to 73% in September. For more details on February weather conditions, you can check Aosta weather in March.
September and April exhibit notable differences in weather patterns. In September, temperatures range from a minimum of -7°C (20°F) to a maximum of 20°C (68°F), with an average of 8°C (47°F). The month sees about 64 mm (2.5 in) of precipitation over 14 days, accompanied by a humidity level of 73%. In contrast, April typically experiences colder conditions, with temperatures ranging from a minimum of -16°C (4°F) to a maximum of 12°C (54°F) and an average temperature of 0°C (32°F). This month has higher precipitation of 83 mm (3.3 in) across 11 days, coupled with a humidity level of 83%. For a more detailed look at April's weather, you can refer to Aosta weather in April.
September and May exhibit contrasting weather patterns, with September generally being milder than May. In September, temperatures range from a minimum of -7°C (20°F) to a maximum of 20°C (68°F), while May sees colder temperatures, dipping as low as -12°C (11°F) and peaking at 18°C (65°F). Additionally, September experiences an average temperature of 8°C (47°F), compared to May's average of 4°C (40°F). However, May is notably wetter, with 144 mm (5.7 in) of precipitation over 20 days, compared to September's 64 mm (2.5 in) over 14 days. Both months exhibit high humidity levels, with May slightly higher at 78% compared to September's 73%. For more details on May weather, check out Aosta weather in May.
September and June exhibit notable differences in weather patterns. In September, the temperatures range from a chilly minimum of -7°C (20°F) to a pleasant maximum of 20°C (68°F), with an average of 8°C (47°F). Meanwhile, June brings milder conditions, with temperatures ranging from -3°C (27°F) to a warm 25°C (77°F) and an average of 10°C (50°F). Precipitation in June is higher, totaling 104 mm (4.1 in) over 18 days, compared to September's 64 mm (2.5 in) over 14 days. Humidity levels are similar, with September at 73% and June slightly higher at 75%. For more detailed information about the weather in June, you can visit Aosta weather in June.
In comparing the weather between September and July, we see notable differences in temperature and precipitation. September experiences a wider range of temperatures, with a minimum of -7°C (20°F) and a maximum of 20°C (68°F), averaging around 8°C (47°F). In contrast, July is milder, with temperatures ranging from 1°C (34°F) to a maximum of 25°C (76°F) and an average of 12°C (55°F). Precipitation is also more significant in July, totaling 98 mm (3.9 in) over 16 days, compared to September's 64 mm (2.5 in) over 14 days. Both months have similar humidity levels, with September at 73% and July at 72%. For more details about July conditions, you can visit Aosta weather in July.
In comparing the weather between August and September, we see a notable decline in temperature as summer transitions into autumn. September's average temperature is 8°C (47°F), with a range from -7°C (20°F) to a maximum of 20°C (68°F), while August experiences warmer averages at 12°C (54°F), with temperatures ranging from a minimum of 0°C (33°F) to a maximum of 23°C (74°F). Additionally, September has a total of 64 mm (2.5 in) of precipitation over 14 days, which is less than August's 101 mm (4.0 in) over the same number of days. Humidity levels also rise slightly in September to 73%, compared to 63% in August. For more details on August weather in Aosta, you can check this link: Aosta weather in August.
In September, temperatures in Aosta typically range from a minimum of -7°C (20°F) to an average of 8°C (47°F), reaching a maximum of 20°C (68°F). The month experiences about 64 mm (2.5 in) of precipitation over 14 days, with a humidity level of 73%. In contrast, October sees a notable drop in temperatures, with a minimum of -8°C (17°F), an average of 4°C (39°F), and a maximum of 15°C (60°F). This month also brings increased precipitation, totaling 124 mm (4.9 in) over 13 days, accompanied by higher humidity at 89%. For more detailed information, check out Aosta weather in October.
September and November present contrasting weather conditions as autumn progresses into winter. In September, temperatures range from a minimum of -7°C (20°F) to a pleasant maximum of 20°C (68°F), with an average of 8°C (47°F). The month experiences relatively moderate precipitation of 64 mm (2.5 in) over 14 days and a humidity level of 73%.
In stark contrast, November sees much colder temperatures, with a minimum of -23°C (-9°F) and an average of -3°C (27°F), although highs can still reach 12°C (54°F). This month brings more considerable precipitation at 117 mm (4.6 in) across 15 days and higher humidity at 90%. For more detailed information, visit Aosta weather in November.
In September, the weather is generally milder with temperatures ranging from a minimum of -7°C (20°F) to a maximum of 20°C (68°F), averaging around 8°C (47°F). The month experiences about 64 mm (2.5 in) of precipitation over approximately 14 days, accompanied by a humidity level of 73%. In contrast, December brings much colder conditions, with temperatures dipping significantly lower, reaching a minimum of -23°C (-9°F) and a maximum of only 4°C (39°F), resulting in an average temperature of -8°C (18°F). Precipitation increases to 165 mm (6.5 in) over about 17 days, and humidity rises to 90%. For more specifics on December weather, you can check Aosta weather in December.
As September unfolds in Aosta, the crisp air marks a distinct transition from the warmer summer months. With temperatures averaging around 8°C (47°F) and highs reaching 20°C (68°F), this month offers a refreshing respite from the heat, making it ideal for outdoor activities. While the average humidity hovers at 73%, the prevalence of rainfall—about 64 mm across 14 days—brings life back to the landscape, turning the surroundings into a vibrant tapestry of autumn hues. The shift in weather not only invites visitors to explore the stunning scenery but also provides a cozy atmosphere for enjoying local delicacies. For a deeper understanding of seasonal changes, check out the detailed insights at Aosta Climate.