Last updated: August 27, 2025
In September, Slovenia experiences a delightful transition as summer eases into autumn. With maximum temperatures peaking at 29°C (85°F) and an average of 15°C (60°F), the weather remains pleasantly warm, although nights can be cooler with minimums dipping to 1°C (34°F). This month also witnesses a notable precipitation amount of 134 mm (5.3 in) spread over approximately 13 days, contributing to a relatively high humidity level of 74%. This mixture of warmth and moisture creates a vibrant landscape, making September an ideal time to explore Slovenia's natural beauty and cultural heritage.
As September unfolds in Slovenia, it marks the transition from the sweltering summer to the cooler embrace of autumn. Daytime temperatures can reach a pleasant maximum of 29°C (85°F), offering a last taste of summer warmth, while nights cool down to a crisp 1°C (34°F). This month boasts an average temperature of 15°C (60°F), a comfortable sweet spot for outdoor explorations. The noticeable drop in temperatures toward the month's end hints at the approaching change of seasons, making it an ideal time to witness the picturesque landscapes begin their transformation into a canvas of autumn hues.
September marks a significant transition in Slovenia's precipitation patterns, with 134 mm (5.3 in) of rain falling over approximately 13 days. This notable increase in rainfall not only surpasses the preceding summer months but also hints at the forthcoming autumnal shift. Following the warm and relatively dry summer, September's precipitation is a precursor to the wetter months ahead, as the landscape begins to embrace the refreshing embrace of fall. The robust rainfall during this period contributes to the vibrancy of Slovenia’s lush greenery, showcasing nature's resilience and setting the stage for the colorful changes that autumn brings.
September in Slovenia experiences a noticeable shift in humidity, settling at a comfortable 74%. This marks a slight increase from the summer months, where August dipped to 68%, reflecting the gradual transition into the cooler fall season. As temperatures begin to drop, the humidity levels slightly rise again, preparing for the higher moisture content typical of autumn. Compared to earlier months, the trend shows a decline from the 91% humidity of January to September's more moderate levels, indicating a gradual easing of the summer swelter. The overall pattern signals a shift towards a more refreshing atmosphere, perfect for enjoying Slovenia's picturesque landscapes as the leaves start to change.
As summer fades into autumn, September in Slovenia sees a notable shift in the UV Index, dropping to a high level of 6. This translates to a burn time of 25 minutes, reminding us that even as temperatures cool, protective measures remain essential. Following the peak months of July and August, which boasted very high UV ratings, the September sun still demands attention. With a gradual decline in UV exposure into October, outdoor enthusiasts are encouraged to enjoy the lingering warmth while staying vigilant against UV radiation. For more detailed insights, check out the UV Index to plan your sun-safe adventures effectively.
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As summer edges into autumn, September in Slovenia still enjoys a delightful 306 hours of sunshine, albeit a noticeable decline from the sun-drenched heights of July and August. This month marks the transition from the peak of summer with its 414 hours in July, gradually tapering off as the days grow shorter. With the bright rays of May and June leading the charge, September retains a remarkable amount of sun, making it an ideal time for outdoor activities amid the picturesque autumn scenery. While daylight diminishes into the cozy embrace of October's 272 hours, September still shines as a bridge between the vibrant summer days and the crisp fall ambiance, inviting visitors to bask in its warm glow before winter approaches.
September in Slovenia offers a refreshing blend of summer's warmth and autumn's embrace, with a 50% chance of sunny weather. This is a notable improvement compared to the preceding months, where sunshine probabilities begin to dip after the vibrant summer. Notably, June and July hold the highest chances of sun at 51% and 47%, respectively, while September maintains a solid mid-range likelihood. As the year progresses, a clear trend emerges: the probabilities of sunny days tend to decrease significantly from the early summer into late autumn, making September a sweet spot for those looking to enjoy the last rays of sunshine before the colder days set in.
As summer gives way to autumn in Slovenia, September brings a gentle transition in daylight duration, offering around 12 hours of natural light each day. This marks a noticeable decrease from the sun-drenched days of July and August, which boast up to 15 hours of daylight. The gradual shift from the long days of summer highlights the progression toward shorter daylight hours, a trend that continues into October with only 10 hours remaining. Although September's daylight is less than the enchanting summer months, it still captures the beauty of early fall, where the vibrant landscapes start to transform in preparation for the quieter months ahead.
As September unfolds in Slovenia, the average wind speed gently settles at 1.6 m/s (4 mph), marking a subtle decline from the summer's gentle breezes. Throughout the year, wind speeds show a consistent rhythm, peaking subtly in spring and early summer, then tapering off as autumn approaches. Notably, August experiences the calmest winds, while the resilience of 1.6 m/s in September hints at a lingering warmth in the air, inviting outdoor adventures before the chill of fall sets in. This trend reflects a balanced transition, where the whispers of the wind echo the changing seasons, creating a serene backdrop for all who wander through Slovenia’s picturesque landscapes.
Weather in varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in , focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present a stark contrast in weather conditions. In September, temperatures range from a minimum of 1°C (34°F) to a maximum of 29°C (85°F), with an average of 15°C (60°F), accompanied by significant precipitation of 134 mm (5.3 in) over 13 days, and a humidity level of 74%. In contrast, January features much colder temperatures, with a minimum of -18°C (0°F) and a maximum of 12°C (54°F), averaging around 0°C (32°F). Precipitation is markedly lower at 39 mm (1.5 in) over just 6 days, but the humidity is higher at 91%. For a more detailed look at the weather patterns in January, you can visit weather in January.
September and February present contrasting weather conditions. In September, temperatures range from a chilly 1°C (34°F) at night to a warm 29°C (85°F) during the day, with an average of 15°C (60°F). This month also experiences higher precipitation, totaling 134 mm (5.3 in) over approximately 13 days, and the humidity level sits at a comfortable 74%.
In contrast, February is much colder, with minimum temperatures plummeting to -14°C (7°F) and a daytime high of 19°C (66°F), averaging just 3°C (38°F). Precipitation is lower at 68 mm (2.7 in) over 8 days, but the humidity rises to 87%, creating a brisk and damp atmosphere. For more details, check out the weather in February.
September and March present contrasting weather conditions. In September, temperatures range from a minimum of 1°C (34°F) to a maximum of 29°C (85°F), with an average of 15°C (60°F). This month experiences more precipitation, totaling 134 mm (5.3 in) over approximately 13 days, with humidity around 74%. In contrast, March has colder temperatures, with a minimum of -13°C (8°F) and a maximum of 21°C (71°F), averaging at 6°C (42°F). The precipitation is significantly lower at 60 mm (2.4 in) over about 10 days, coupled with higher humidity at 82%. For more detailed insights, you can check the weather in March.
In comparing the weather between September and April, we see notable differences in temperature and precipitation. September boasts a more moderate average temperature of 15°C (60°F), with maximum highs reaching up to 29°C (85°F). This month typically experiences 134 mm (5.3 in) of precipitation over 13 days, with a humidity level of 74%. In contrast, April presents cooler conditions, with average temperatures around 10°C (50°F) and minimum lows plunging to -10°C (14°F). Precipitation is lighter at 94 mm (3.7 in) over 12 days, accompanied by slightly higher humidity at 79%. For a closer look at the weather specifics, you can explore weather in April.
In comparing the weather of September and May, both months exhibit similar humidity levels, averaging 74%. September typically showcases a wider temperature range, with minimums of 1°C (34°F) and maximums reaching up to 29°C (85°F), while May's temperatures hover slightly lower, with minimums at 0°C (32°F) and maximums at 28°C (83°F). Rainfall is more frequent in May, with precipitation occurring on 19 days and totaling 150 mm (5.9 in), compared to September's 134 mm (5.3 in) over 13 days. This makes May a wetter month overall, which may impact outdoor activities. For a detailed look at weather in May, visit the link.
In comparing the weather of September and June, we see notable differences in temperature and precipitation patterns. September experiences a broader range of temperatures, with minimums dipping to 1°C (34°F) and maximums reaching up to 29°C (85°F), averaging 15°C (60°F). In contrast, June presents a milder climate, with minimum temperatures of 5°C (42°F) and a maximum reaching 34°C (93°F), resulting in an average of 19°C (67°F). Additionally, September is wetter, receiving 134 mm (5.3 in) of precipitation over 13 days, while June has less rainfall at 89 mm (3.5 in) over 14 days. Both months boast similar humidity levels, hovering around 74% in September and 75% in June. For more details, you can check the weather in June.
In comparing the weather of September and July, we observe notable differences in temperature and precipitation patterns. September experiences cooler temperatures, with a minimum of 1°C (34°F) and an average of 15°C (60°F), while July boasts warmer conditions, featuring a minimum of 10°C (49°F) and an average of 21°C (69°F). Both months receive similar amounts of precipitation—September with 134 mm (5.3 in) over 13 days and July slightly less with 132 mm (5.2 in) spread across 15 days. Interestingly, the humidity levels remain constant at 74% for both months, creating a consistently damp atmosphere. For a deeper insight into July's weather, you can check out this link: weather in July.
In comparing the weather of September and August, we see significant differences in temperature and precipitation. August generally enjoys warmer conditions, with minimum temperatures around 7°C (45°F) and averages peaking at 21°C (69°F), whereas September sees a drop, with minimums dipping to just 1°C (34°F) and averages around 15°C (60°F). Additionally, August experiences higher maximum temperatures, reaching up to 35°C (96°F), while September's maximum is 29°C (85°F). Precipitation levels also vary slightly; September has 134 mm (5.3 in) of rainfall over 13 days, compared to August's 114 mm (4.5 in) over 14 days. Humidity tends to be higher in September at 74%, compared to 68% in August. For more detailed insights, you can check the weather in August.
In September, temperatures range from a low of 1°C (34°F) to a high of 29°C (85°F), with an average of 15°C (60°F). The month experiences considerable rainfall, totaling 134 mm (5.3 in) over 13 days, accompanied by a humidity level of 74%. In contrast, October sees a drop in temperatures, with the minimum reaching -1°C (30°F) and a maximum of 23°C (74°F), averaging at 11°C (52°F). Precipitation decreases to 76 mm (3.0 in) over 9 days, and humidity rises to 88%. For more detailed insights, you can check the weather in October.
In comparing the weather between September and November, September boasts a wider temperature range, with minimums around 1°C (34°F) and maximums reaching 29°C (85°F), making it generally warmer. The average temperature in September is 15°C (60°F) and experiences 134 mm (5.3 in) of precipitation over approximately 13 days, accompanied by a humidity level of 74%. In contrast, November brings colder conditions, with minimum temperatures dropping to -7°C (20°F) and average temperatures sitting at 6°C (43°F), peaking at 20°C (68°F). Despite having slightly lower precipitation at 108 mm (4.2 in) over about 10 days, November's humidity soars to 90%, adding to the overall dampness of the month. For more detailed information, you can check the weather in November.
September and December weather present a stark contrast. In September, temperatures can range from a mild minimum of 1°C (34°F) to a warm maximum of 29°C (85°F), with an average of 15°C (60°F). The month sees about 134 mm (5.3 in) of precipitation spread over 13 days, and humidity levels hover around 74%. In contrast, December brings much colder conditions, with temperatures dropping significantly, ranging from a chilling minimum of -17°C (2°F) to a maximum of 14°C (58°F), and an average temperature close to freezing at 1°C (35°F). Precipitation decreases to 94 mm (3.7 in) over 9 days, while humidity rises to 89%, making the air feel even colder. For a more detailed look, you can check the weather in December.
As summer fades, September introduces a refreshing shift in weather that sets the stage for the upcoming autumn months. With temperatures ranging from mild averages to brisk lows, this month is distinctively cooler than the sweltering summer days. The increased humidity level contributes to an invigorating atmosphere, though it also brings about substantial precipitation, often enveloping the landscape in a lush, green embrace. While September may see rain on several days, it offers a unique charm with its vibrant foliage and cooler air, creating a perfect backdrop for outdoor activities. For a detailed exploration of weather patterns, visit our Climate page.