Last updated: August 27, 2025
September in Slovenia offers a beautiful transition into autumn, with temperatures ranging from a comfortable maximum of 28°C (83°F) to a brisk minimum of 0°C (33°F). The month boasts an average temperature of 15°C (59°F), perfect for outdoor activities. However, visitors should prepare for occasional rain, as 170 mm (6.7 in) of precipitation falls over about 13 days, resulting in a humidity level of around 74%. This blend of warm days and cooler nights makes September an ideal time to explore Slovenia's stunning landscapes and rich culture.
As September arrives in Slovenia, the weather begins to shift, marking the transition from the warmth of summer to the cooler embrace of autumn. With minimum temperatures hovering around 0°C (33°F) and comfortable average highs reaching 28°C (83°F), the month retains a pleasant warmth, inviting outdoor activities. Days are still filled with sunshine, but as the month progresses, temperatures gradually decline, paving the way for the crispness of October. This moderate climate makes September an ideal time to explore Slovenia's stunning landscapes, where the first hints of fall foliage enrich the scenery, offering a delightful backdrop for hiking and sightseeing. As the warmth lingers, the overall ambiance invites a sense of relaxation and appreciation for the natural beauty that abounds.
September marks a significant shift in Slovenia's precipitation patterns, with an impressive 170 mm (6.7 in) of rainfall, making it the wettest month of the year. This spike contrasts with the drier summer months, as August sees 146 mm (5.8 in) and July 122 mm (4.8 in). The trend is further highlighted by the 13 precipitation days, offering a refreshing respite after the height of summer, while still maintaining a moderate frequency compared to the more substantial rainfall typically associated with spring. As the country transitions into autumn, this increase not only enriches the lush landscapes but also prepares the ground for the wetter months ahead, showcasing Slovenia's dynamic climate.
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 transitions to autumn in Slovenia, September brings a UV Index of 7, indicating a high exposure category. This is a slight decrease from the very high levels experienced in the peak summer months of June and July, where the UV Index soared to 9. With a burn time of 25 minutes, it's essential to remain cautious during outdoor activities, especially during midday when the sun's rays are strongest. The trend shows that while the UV Index is lower than the heights of summer, it still necessitates protective measures. As the days grow shorter and the weather begins to cool, it's wise to stay informed about local conditions by checking the UV Index, ensuring a pleasant yet safe experience outdoors.
UV Risk Categories
September in Slovenia offers a delightful balance of sunshine, boasting an impressive 309 hours of bright skies. As summer's warmth transitions into autumn, this month reflects a gentle dip in sunlight after the peak of July, which recorded 415 hours. Notably, September's sunshine is still abundant compared to the earlier months, showcasing an overall upward trend from the chilly depths of winter. Following this vibrant month, October sees a further decrease to 275 hours, signaling the gradual retreat of summer's glow. Embrace the golden days of September, where the lingering warmth of summer still dances in the crisp autumn air.
In Slovenia, September brings a reliable 48% chance of sunshine, making it one of the brighter months of the year. This is a significant improvement compared to the gloomy vibes of November, which plummets to a mere 22% chance of sun. The likelihood of sunny weather peaks during the spring and summer months, with March and June showcasing a healthy 54% and 48% respectively. As summer wanes, September offers an ideal balance, combining pleasant weather and fewer tourists, inviting visitors to relish the beauty of Slovenia's landscapes under mostly clear skies. Enjoying the last rays of summer sun in this charming country is a perfect way to close out the season.
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 unfolds in Slovenia, the average wind speed lingers at a gentle 1.5 m/s (3 mph), mirroring the mild breezes of the preceding months. This period signals a subtle transition as the summer heat begins to wane, creating a serene atmosphere punctuated by soft gusts. Notably, June and August register the calmest winds, with speeds slipping to 1.5 m/s and 1.4 m/s, while the spring months showcase a slight uptick as nature awakens, hinting at more dynamic conditions ahead. As the year progresses into October, we see a minor resurgence to 1.7 m/s (4 mph), illustrating a cycle of ebb and flow that characterizes Slovenia's serene landscapes during this time of year.
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 stark contrasts in weather conditions. In September, temperatures range from a cool 0°C (33°F) at night to a pleasant high of 28°C (83°F) during the day, with an average of 15°C (59°F). This month experiences significant rainfall, totaling 170 mm (6.7 in) across about 13 days, and humidity levels around 74%. In contrast, January is much colder, with temperatures dipping as low as -16°C (3°F) and averaging -1°C (31°F), peaking at just 11°C (52°F). Additionally, January sees minimal precipitation of 51 mm (2.0 in) over 6 days, accompanied by higher humidity at 91%. For a detailed look at this winter month, you can explore the weather in January.
September and February exhibit markedly different weather patterns. In September, temperatures typically range from a cool 0°C (33°F) at night to a comfortable max of 28°C (83°F) during the day, with an average of 15°C (59°F). This month also sees significant rainfall, with about 170 mm (6.7 in) spread over 13 days, accompanied by a humidity level of 74%. In contrast, February is much colder, with temperatures dipping as low as -13°C (9°F) and only reaching a maximum of 18°C (64°F), resulting in an average temperature of just 2°C (36°F). Precipitation is less frequent, totaling around 90 mm (3.5 in) across 10 days, and humidity is notably higher at 87%. For more information, check out the weather in February.
September and March present distinctly different weather patterns. In September, temperatures range from a cool 0°C (33°F) at their minimum to a warm 28°C (83°F) at their peak, with an average of 15°C (59°F). This month also experiences more precipitation, totaling 170 mm (6.7 in) over 13 days, accompanied by a humidity level of 74%. In contrast, March has colder temperatures, with a minimum of -16°C (3°F) and a maximum of 21°C (70°F), averaging around 5°C (40°F). Though precipitation is lower at 80 mm (3.1 in) across 10 days, the humidity is slightly higher at 82%. For more detailed insights on March weather, you can check weather in March.
In September, the weather tends to be warmer, with temperatures ranging from a minimum of 0°C (33°F) to a maximum of 28°C (83°F) and an average of 15°C (59°F). This month also experiences significant precipitation, averaging 170 mm (6.7 in) over about 13 days, accompanied by a humidity level of 74%. In contrast, April typically presents cooler conditions, with temperatures varying from a minimum of -10°C (15°F) to a maximum of 25°C (77°F) and an average of 9°C (49°F). Though there is slightly less precipitation at 113 mm (4.4 in) over 12 days, the humidity is higher, reaching 79%. For more detailed insights into the conditions, check the weather in April.
In comparing the weather in September and May, we see some notable differences. September experiences slightly warmer temperatures, with averages around 15°C (59°F) and maximums reaching 28°C (83°F), while May has a lower average of 13°C (56°F), peaking at 26°C (79°F). Both months have similar levels of precipitation, with September recording 170 mm (6.7 in) over 13 days and May having 168 mm (6.6 in) spread over a longer period of 20 days. Humidity remains consistent at 74% for both months, contributing to the overall dampness. For more detailed information, you can check the weather in May.
In comparing the weather of September to June, we can observe notable differences. September typically has a wider temperature range, with minimums dipping down to 0°C (33°F) and maximums reaching up to 28°C (83°F), resulting in an average of 15°C (59°F). In contrast, June consistently enjoys warmer temperatures, with a minimum of 4°C (39°F) and maximums soaring to 33°C (92°F), averaging around 18°C (66°F). Additionally, while September experiences higher precipitation levels at 170 mm (6.7 in) over 13 days, June has relatively less rainfall at 105 mm (4.1 in) spread across 14 days. The humidity remains fairly similar, with September at 74% and June slightly higher at 75%. For more detailed insights, you can check weather in June.
September and July exhibit notable differences in weather patterns. July typically enjoys warmer temperatures, with an average of 19°C (67°F) and a maximum reaching 31°C (88°F), while September sees cooler averages at 15°C (59°F) and a maximum of 28°C (83°F). In terms of precipitation, September is wetter with 170 mm (6.7 in) over 13 days, compared to July's 122 mm (4.8 in) spread across 16 days. Humidity remains consistent in both months at 74%, but the overall conditions in September feel much cooler and wetter. For a detailed overview of July's climate, you can check the weather in July.
Comparing the weather in September to that of August reveals some notable differences. September experiences cooler temperatures, with a minimum of 0°C (33°F) and an average of 15°C (59°F), whereas August is milder, averaging 20°C (68°F) and reaching a maximum of 33°C (92°F). Additionally, September sees more precipitation, measuring 170 mm (6.7 in) over 13 rainy days compared to August's 146 mm (5.8 in) across 15 days. Humidity also rises slightly in September, sitting at 74% compared to August's 68%. For more details, you can check the weather in August.
September and October showcase a notable transition in weather patterns. In September, temperatures range from a mild 0°C (33°F) at night to a warm 28°C (83°F) during the day, with an average of 15°C (59°F). Precipitation is relatively high at 170 mm (6.7 in), occurring on about 13 days, and humidity hovers around 74%. In contrast, October brings cooler temperatures, with nighttime lows dipping to -1°C (31°F) and daytime highs reaching only 22°C (73°F), averaging at 10°C (50°F). Rainfall declines to 96 mm (3.8 in) over 10 days, while humidity increases to 88%, creating a crisp and damp atmosphere. For more detailed information, you can check the weather in October.
September typically offers milder temperatures, with averages around 15°C (59°F) and maximums reaching up to 28°C (83°F), making it more comfortable for outdoor activities. In contrast, November sees a significant drop in temperature, with average values of just 5°C (42°F) and lows that can plummet to -11°C (12°F). While September experiences about 170 mm (6.7 in) of precipitation over 13 days, November's rainfall is slightly lower at 154 mm (6.1 in) over 11 days, but the humidity is higher at 90%. For a more detailed view of what to expect during this month, you can check the weather in November.
In September, temperatures range from a minimum of 0°C (33°F) to a pleasant maximum of 28°C (83°F), with an average of 15°C (59°F). The month experiences considerable rainfall, totaling 170 mm (6.7 in) over 13 days, and the humidity sits at 74%. In contrast, December brings a chillier climate with temperatures dipping as low as -16°C (3°F) and averaging around 0°C (33°F), peaking at a maximum of 12°C (53°F). Although precipitation decreases to 126 mm (5.0 in) over 11 days, the humidity rises to 89%. For more details, you can check the weather in December.
As September rolls in, the weather undergoes a gentle transition, marking the end of summer and the onset of autumn. With temperatures averaging around 15°C, this month presents a cooler atmosphere compared to the warmer months that preceded it. The increased humidity levels—hovering at 74%—coupled with about 170 mm of rain over 13 days, hint at a shift towards a more moist environment. This change in precipitation is notable, as it paves the way for the vibrant colors of fall while providing a refreshing contrast to the dry heat of the summer months. For a comprehensive understanding of the climate nuances, don't forget to check out the detailed Climate page.