Last updated: August 27, 2025
September in Slovenia showcases a delightful transition from summer to autumn, with temperatures reaching a maximum of 32°C (90°F) and averaging around 17°C (63°F). Visitors can expect a broad range of cooler evenings, dipping to a minimum of 2°C (37°F). While the month experiences some rainfall, totaling 103 mm (4.1 in) over approximately 10 days, the humidity remains moderate at 65%, creating a comfortable atmosphere for outdoor activities. Whether you’re exploring vibrant landscapes or charming towns, this month offers a unique blend of warmth and refreshing breezes, perfect for enjoying Slovenia's natural beauty.
As summer winds down, September in Slovenia ushers in a delightful transition, marked by comfortably mild temperatures. With minimums around 2°C (37°F) and average highs peaking at a pleasant 32°C (90°F), this month reflects a perfect blend of warmth and coolness. The average temperature settles at 17°C (63°F), making it an ideal time for outdoor exploration. Unlike the scorching heat of August, which can reach up to 37°C (100°F), September's temperatures provide a refreshing respite, making it an appealing month for both locals and tourists to experience Slovenia's stunning landscapes. As autumn approaches, the gentle drop in temperatures signals the onset of a beautiful seasonal shift, inviting visitors to soak up the last rays of summer while enjoying the vibrant scenery.
In September, Slovenia experiences a notable uptick in precipitation, with 103 mm (4.1 in) of rain recorded over 10 days. This increase signifies a shift from the drier summer months of July and August, both averaging around 90 mm, reflecting the transition into the wetter autumn season. The fall brings more consistent rainfall, during which the landscape flourishes, revitalized after the summer heat. As October approaches, rainfall decreases to 56 mm (2.2 in), signaling a gradual reduction in precipitation days. This pattern highlights September as a pivotal month of change, where Slovenia's natural beauty is nourished by the rejuvenating rains, setting the stage for the colorful autumn foliage to come.
As summer fades into autumn, September in Slovenia experiences a noticeable shift in humidity, averaging around 65%. This marks a slight increase from the drier summer months, where humidity dipped to 60% in August. The trend throughout the year showcases a gradual decline in humidity from the damp chill of winter, peaking at an impressive 90% in January, before reaching its annual low in July. However, as the season transitions, humidity levels begin to rise once again, hinting at the approaching wetness of fall, which can see percentages soaring back up to 84% by October. This dynamic shift underlines the typical Slovene climate, where the crispness of autumn brings a refreshing yet slightly more humid air.
In September, Slovenia experiences a UV Index of 6, indicating a high exposure category with a burn time of approximately 25 minutes. This marks a slight decrease from the intense heat of summer months, where the UV Index peaked at 9 in both June and July, categorized as very high. As the season shifts, the sunlight becomes less harsh, yet caution remains essential for outdoor activities, especially as the days become shorter. With the UV Index trending downward from the peak summertime levels, it’s a great time to enjoy the beautiful Slovenian outdoors while still protecting your skin. For more details, check the comprehensive UV Index resource.
UV Risk Categories
As summer transitions to autumn, September in Slovenia continues to bask in a generous 323 hours of sunshine. This marks a notable decline from the sun-drenched days of July and August, which enjoy the peak of summer with 424 and 389 hours, respectively. However, September still boasts a vibrant glow, reminiscent of the 367 hours seen in May, providing a perfect backdrop for outdoor adventures and scenic explorations. While the days gradually shorten, the lingering summer warmth ensures that the month retains a delightful charm, serving as a pleasant farewell to the summer season before the cooler temperatures of October set in with 286 hours. This gradual shift hints at nature's rhythm, inviting both locals and travelers to savor the bright, crisp days of early fall.
September in Slovenia brings a promising 51% chance of sunny weather, marking a notable transition as the summer months start to wane. This month stands out with a slight increase in sunshine likelihood compared to the previous summer, particularly when juxtaposed with the sunnier July and August, which hover around 44% to 47%. As summer's grip loosens, September offers a delightful balance—a blend of occasional sunny days alongside the early hints of autumn, making it an inviting time to explore the stunning landscapes of Slovenia. With a favorable prediction of sun, it’s the perfect month for outdoor adventures or simply basking in the warm Slovenian sun.
As summer gracefully transitions into autumn, September in Slovenia offers a delightful 12 hours of daylight, marking a gradual decline from the sun-drenched days of July and August, which boast 15 hours of light. This month serves as a bridge between the vibrant long days of summer and the shorter, cozier days of fall. Following the peak daylight duration in June, visitors can observe that as nature begins to prepare for the cooler months ahead, daylight starts to wane. The steady decrease in daylight hours that commenced in late summer highlights the seasonal rhythm, inviting both locals and travelers to savor the perfect balance of warmth and evening sunsets before the days shrink further into October's 10 hours of light.
As September arrives in Slovenia, the gentle caress of the wind mirrors the transition of seasons. With an average wind speed of 1.9 m/s (4 mph), this month finds itself on par with the soft breezes of August, both embracing a calmness that hints at the approaching autumn. A notable dip in wind speed during the summer months showcases a serene atmosphere, while prior months like April and March had boasted slightly brisker conditions. This trend suggests a gradual shift towards more tranquil weather as the region gears up for the cooler months ahead. The mildness of September’s winds invites leisurely strolls and outdoor activities, making it a delightful time to savor the beauty of Slovenia's natural 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.
In September, the weather is generally warm, with temperatures ranging from a chilly 2°C (37°F) at night to a pleasant average of 17°C (63°F) during the day, peaking at a hot 32°C (90°F). With 103 mm (4.1 in) of precipitation spread over about 10 days, the humidity sits around 65%, creating a comfortable atmosphere for outdoor activities. In contrast, January experiences much colder temperatures, with a minimum of -12°C (10°F) and an average of 1°C (33°F), peaking at a mild 15°C (59°F). Although the precipitation is significantly lower at 29 mm (1.1 in) over just 6 days, the humidity is higher at 90%, contributing to a sharp, frosty air typical of winter. For a deeper look at the specifics of winter conditions, you can check the weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a chilly 2°C (37°F) at night to a warm 32°C (90°F) during the day, with an average of 17°C (63°F). The month sees more rainfall, with a total precipitation of 103 mm (4.1 in) over approximately 10 days, and a humidity level of 65%. In stark contrast, February experiences colder conditions, with minimum temperatures plummeting to -12°C (10°F) and a milder maximum of 20°C (68°F), averaging only 4°C (39°F). Precipitation is significantly lower at 44 mm (1.7 in) over 8 days, but the humidity is notably higher at 84%. For more details, check the weather in February.
The weather in September is typically warmer and more variable compared to March. September boasts temperatures ranging from a mild 2°C (37°F) at night to a pleasant average of 17°C (63°F), peaking at a warm 32°C (90°F). In contrast, March features a chillier climate, with temperatures dipping down to -18°C (0°F) at night and averaging around 7°C (44°F), with a maximum of 23°C (73°F). September also sees more rainfall, with 103 mm (4.1 in) over about 10 days, while March has significantly less precipitation at 37 mm (1.4 in) over 8 days. Additionally, March experiences higher humidity levels at 78%, compared to September's 65%. You can find more detailed information about weather in March.
When comparing the weather in September and April, several notable differences emerge. September typically experiences a wider temperature range, with minimums around 2°C (37°F) and maximums peaking at 32°C (90°F), leading to an average temperature of 17°C (63°F). In contrast, April sees cooler conditions, with temperatures ranging from a minimum of -5°C (23°F) to a maximum of 28°C (82°F), averaging 11°C (53°F). Additionally, September receives significantly more rainfall at 103 mm (4.1 in) compared to April’s 49 mm (1.9 in), though both months have precipitation on about 10 days. Interestingly, April's humidity is slightly higher at 73%, compared to September's 65%. For a deeper insight into the characteristics of April weather, you can check the detailed information here: weather in April.
In September, temperatures vary significantly, with a minimum of 2°C (37°F), an average of 17°C (63°F), and a maximum reaching 32°C (90°F). This month experiences about 103 mm (4.1 in) of precipitation over approximately 10 days, accompanied by a humidity level of 65%. In contrast, May offers slightly cooler conditions, with temperatures ranging from a minimum of 1°C (35°F) to a maximum of 31°C (88°F), and an average of 16°C (60°F). Precipitation in May is higher at 117 mm (4.6 in) spread across around 17 days, along with a higher humidity level of 71%. For more details on the weather conditions, you can check the weather in May.
In comparing the weather of September and June, we notice distinct differences in temperature and precipitation patterns. September experiences a wider temperature range, with lows of 2°C (37°F) and highs reaching 32°C (90°F), averaging around 17°C (63°F). In contrast, June typically has milder temperatures, starting at a minimum of 8°C (47°F) and peaking at 35°C (95°F), with an average of 21°C (70°F). When it comes to precipitation, September has slightly more rainfall, totaling 103 mm (4.1 in) over about 10 days, compared to June's 90 mm (3.5 in) over 12 days. The humidity in June is also higher at 73%, compared to September's 65%. For more details, you can check the complete weather in June.
In comparing the weather between September and July, September offers a greater temperature range, with a minimum of 2°C (37°F) and a maximum of 32°C (90°F), while July features milder conditions, starting at 10°C (51°F) and peaking at 35°C (96°F). July is generally warmer with an average temperature of 22°C (72°F) compared to September's 17°C (63°F). Additionally, September sees slightly more precipitation at 103 mm (4.1 in) over 10 days, whereas July has 86 mm (3.4 in) spread over 13 days. Humidity levels are also marginally higher in July at 70%, compared to September's 65%. For more detailed insights, you can check the weather in July.
In comparing the weather between August and September, we can observe notable differences. August typically experiences higher temperatures, with minimums around 9°C (48°F) and maximums peaking at 37°C (100°F), leading to an average of 22°C (72°F). In contrast, September shows a decrease in temperature, ranging from a minimum of 2°C (37°F) to a maximum of 32°C (90°F), yielding an average of 17°C (63°F).
Precipitation is slightly higher in September, totaling 103 mm (4.1 inches) over 10 days, compared to August's 90 mm (3.5 inches) over 11 days; however, September benefits from slightly higher humidity at 65%, compared to August's 60%. For more detailed insights, you can check the weather in August.
In September, the weather experiences a wider temperature range with minimums around 2°C (37°F) and maximums reaching up to 32°C (90°F), averaging 17°C (63°F). The month sees considerable precipitation, totaling 103 mm (4.1 in) over about 10 days, with a humidity level of 65%. In contrast, October brings cooler temperatures, with minimums dropping to 0°C (32°F) and maximums capping at 26°C (79°F), leading to an average of 12°C (54°F). Precipitation decreases significantly to 56 mm (2.2 in) over just 8 days, while humidity rises to 84%. For more details, you can check the weather in October.
September and November present quite distinct weather patterns. In September, temperatures range from a mild 2°C (37°F) at night to a warm 32°C (90°F) during the day, with an average of 17°C (63°F). This month experiences a considerable amount of rainfall, totaling 103 mm (4.1 in) over 10 days and a humidity level of 65%, making it feel rather comfortable overall. In stark contrast, November sees temperatures drop significantly, with minimums reaching -6°C (22°F), average highs of only 7°C (44°F), and a maximum of 20°C (68°F). With a total precipitation of 72 mm (2.8 in) over 9 days and a much higher humidity level of 89%, November definitely feels much colder and damper. For more detailed insights, you can check the weather in November.
September and December present a striking contrast in weather conditions. In September, temperatures range from a mild 2°C (37°F) at night to a warm 32°C (90°F) during the day, with an average of 17°C (63°F). There's a moderate level of precipitation at 103 mm (4.1 in) over approximately 10 days, and the humidity hovers around 65%. In contrast, December sees much colder temperatures, with a minimum of -6°C (21°F) and a maximum of 17°C (63°F), averaging just 2°C (37°F). Precipitation decreases to 61 mm (2.4 in) over about 9 days, but humidity rises significantly to 89%. For more details, you can check the weather in December.
As summer begins to fade, September weather presents a unique transition marked by a delightful mix of warmth and coolness. Daytime temperatures can reach up to a comfortable 32°C, yet evenings may dip to a chilly 2°C, creating a diverse range of experiences for locals and visitors alike. With an average temperature hovering around 17°C, the month also brings an increase in humidity at 65%, making it feel quite different from the sweltering summer. Rainfall is more frequent, with 10 days of precipitation contributing to a total of 103 mm. This balance of sun and showers sets September apart from the hotter months, creating an inviting atmosphere perfect for outdoor activities. For a deeper understanding of the climate patterns throughout the year, explore more about the Climate in this region.