September Weather in , Slovenia

Last updated: August 27, 2025

In September, Slovenia experiences a dynamic interplay of weather, with temperatures fluctuating from a pleasant average of 16°C (61°F) to maximum highs reaching 32°C (89°F). The season transitions bring cooler nights, where temperatures can dip to a brisk minimum of 3°C (37°F). Though this month marks the onset of autumn, it also brings moderate rainfall, accumulating to 145 mm (5.7 in) over approximately 12 days, resulting in a humidity level of around 65%. This blend of warmth and moisture crafts a landscape that is both invigorating and lush, making September an ideal time to explore Slovenia's natural beauty.

September Temperature in

As summer fades into autumn, September in Slovenia showcases a delightful transition in temperatures. The month greets visitors with a minimum of 3°C (37°F), offering a crisp freshness, while daytime warmth peaks at a pleasant 32°C (89°F). With an average temperature of 16°C (61°F), this month strikes a charming balance between the lingering warmth of summer and the coolness that heralds fall. The clear skies and mild weather create an ideal backdrop for outdoor activities, making it a wonderful time to explore Slovenia's breathtaking landscapes before the chill of October sets in.

September Weather in : Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in , showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In , September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec333843525969707061534336
Data source: Temperature data for generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in

In September, Slovenia experiences a notable peak in precipitation, with 145 mm (5.7 in) of rainfall recorded over approximately 12 days. This increase continues the trend from the summer months, where moisture levels were significant, particularly in May and July. As the country transitions into autumn, the rainfall not only surpasses the typical amounts seen earlier in the year, but it also indicates a shift toward a wetter climate. The cumulative effect of increased precipitation creates lush landscapes, fostering vibrant flora and maintaining the region's lush green charm as it prepares for the cooler months ahead.

September Precipitation Trends in

The chart displays monthly precipitation patterns in , with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In , September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec3458527313893114103145698771
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in

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.

September Average Humidity in

This chart illustrates the average monthly humidity levels in , with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec90%84%78%73%71%73%70%60%65%84%89%89%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in

As summer fades into autumn, September in Slovenia presents a noticeable shift in the UV Index, dropping to 6, categorizing it as high. This reduction from the peak summer levels, where the UV Index reached as high as 9, indicates that while sun exposure is still significant, the risk of harm is somewhat lower. With a burn time of 25 minutes, it's essential to remain vigilant about sun protection, especially during midday. This transition mirrors the general trend in UV exposure throughout the year, where winter months see minimal UV activity and safer exposure times. For more details on managing sun safety throughout the year, check out the UV Index.

Maximum UV Index Levels in for September

The chart shows the monthly maximum UV Index (UVI) for in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec235689986432
Data source: September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in

As summer gracefully transitions into autumn, September in Slovenia offers a delightful balance of warmth and light. With 318 hours of sunshine, it stands out as a vibrant month, nestled comfortably between the sun-drenched peaks of July and August and the cooler embrace of October. This notable decline from the previous months signals the gradual change of seasons, yet still holds onto a generous amount of sunlight. Following the peak summer months, September presents a perfect opportunity for outdoor activities amidst the stunning fall foliage, making it an ideal time to savor Slovenia's natural beauty as daylight begins to wane.

Monthly Sunshine Duration in : September Highlighted

The September sunshine duration represents the total number of hours experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec164h218h300h334h363h401h422h388h318h284h199h203h
Data source: September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in During September

In September, Slovenia enjoys a favorable chance of sunny weather, with a 53% likelihood of sunshine. This trend is particularly noteworthy as it aligns with the summery vigor of the preceding months, like June and July. The transition into autumn sees a slight dip in sunshine probabilities compared to the peak summer months, yet September stands out as a reliable option for those seeking clear skies. As the days begin to cool, this retaining of summer-like sunlight sets the stage for pleasant outdoor activities amidst the stunning landscapes of Slovenia.

Percentage of Sunny Days in September in

The chart illustrates the percentage of sunny days in throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec29%51%54%38%37%53%47%43%53%42%26%33%
Data source: September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in in September

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.

Average Daylight Hours in for September

The chart illustrates the variation in daylight duration in throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 2m10h 19m11h 56m13h 35m15h15h 44m15h 21m14h 5m12h 30m10h 51m9h 23m8h 38m
Data source: daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in

As September arrives in Slovenia, the average wind speed remains a gentle 1.7 m/s (4 mph), mirroring the calm breezes of August. This continuation of subdued winds signals a transition from the slightly more blustery spring months, where speeds peaked at 2.6 m/s (6 mph) in April and May. While autumn typically ushers in cooler temperatures, the consistent light winds of September create a serene backdrop, perfect for enjoying the stunning fall foliage. As the month progresses, however, wind speeds are expected to rise slightly again in October, potentially invigorating the landscape and reminding us that change is always just around the corner.

Average September Wind Speed in

The chart displays monthly wind speed patterns in , with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec2.42.42.32.62.62.02.21.71.7 m/s2.41.72.0
Data source: September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Compares to Other Months

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 strikingly contrasting weather patterns. In September, temperatures range from a mild 3°C (37°F) at night to a warm 32°C (89°F) during the day, with an average of 16°C (61°F). This month experiences considerable rainfall, totaling 145 mm (5.7 in) over about 12 days, along with a humidity level of 65%. In contrast, January brings much colder conditions, with temperatures plummeting to a minimum of -17°C (1°F) and averaging just 0°C (33°F), while peaking at 14°C (57°F). The precipitation is significantly lower at 34 mm (1.3 in) across only 6 days, but the humidity remains high at 90%. For more details on January's weather, visit weather in January.

September and February present strikingly different weather patterns. In September, temperatures range from a cool 3°C (37°F) at night to a warm 32°C (89°F) during the day, with an average of 16°C (61°F). The month experiences significant rainfall, totaling 145 mm (5.7 in) over approximately 12 days, and the humidity sits at a moderate 65%. In contrast, February brings much colder conditions, with nighttime lows plunging to -12°C (11°F) and daytime highs reaching only 20°C (68°F), averaging around 4°C (39°F). Rainfall is considerably less, with only 58 mm (2.3 in) across 9 days, and the humidity rises to 84%. These contrasting months highlight the transition from the warmth of late summer to the chill of mid-winter. For more detailed information about weather in February, please check the link.

September generally features milder temperatures, with daytime highs reaching up to 32°C (89°F) and an average of 16°C (61°F), whereas March is much cooler, with maximum temperatures around 22°C (72°F) and an average of only 6°C (43°F). Additionally, March experiences significantly colder minimum temperatures, dropping as low as -18°C (0°F), compared to September's mild minimum of 3°C (37°F). Precipitation is more frequent in September, accumulating around 145 mm (5.7 in) over 12 days, while March has a more moderate 52 mm (2.1 in) of precipitation across 9 days. Humidity levels also peak in March at 78%, compared to September's 65%. For more detailed information on the weather in March, visit weather in March.

September and April showcase distinct weather contrasts, highlighting the transition from the warmth of summer to the cooler embrace of autumn. In September, temperatures can range from a chilly 3°C (37°F) at night to a balmy 32°C (89°F) during the day, with an average of 16°C (61°F). This month also sees a significant amount of precipitation, totaling 145 mm (5.7 in) over approximately 12 days, accompanied by a humidity level of 65%. Conversely, April experiences cooler temperatures, dipping as low as -7°C (19°F) at night and peaking at 27°C (81°F), with an average of 11°C (52°F). Rainfall is lighter in April, with total precipitation of 72 mm (2.9 in) over about 11 days and a slightly higher humidity of 73%. For a more detailed overview, you can check the weather in April.

When comparing the weather in September and May, both months exhibit mild temperatures, but September tends to be slightly warmer overall. September's average temperature is 16°C (61°F), peaking at 32°C (89°F), while May has a slightly lower average of 15°C (59°F) and a maximum of 31°C (88°F). Precipitation levels are relatively similar, with September receiving 145 mm (5.7 in) over 12 days, compared to May's 138 mm (5.4 in) over 17 days. Additionally, September's humidity at 65% is a touch lower than May's 71%, suggesting May may feel a bit more humid. For more information, check out the weather in May.

When comparing the weather in September and June, we see notable differences in temperature and precipitation. September experiences a broader temperature range, with a minimum of 3°C (37°F) and a maximum of 32°C (89°F), leading to an average of 16°C (61°F). In contrast, June has a warmer average temperature of 20°C (69°F), with minimums of 7°C (45°F) and maximums reaching up to 36°C (96°F). Precipitation is heavier in September, totaling 145 mm (5.7 in) over 12 days, compared to June's 93 mm (3.7 in) across 13 days. Humidity levels are slightly higher in June at 73%, while September's humidity sits at 65%. For more details, check the weather in June.

When comparing the weather in September to that in July, notable differences emerge in temperature and precipitation. September experiences a wider temperature range, with a minimum of 3°C (37°F), an average of 16°C (61°F), and a maximum of 32°C (89°F), while July tends to be warmer with temperatures ranging from a minimum of 9°C (49°F) to a maximum of 35°C (94°F) and an average of 21°C (70°F). In terms of precipitation, September sees a higher total of 145 mm (5.7 in) over 12 days, compared to July's 114 mm (4.5 in) spread over 14 days. Humidity levels are relatively high in both months, with July at 70% and September at 65%. For a more detailed look at July's weather, check out weather in July.

In comparing the weather between August and September, we see notable differences in temperature and precipitation. September experiences a more significant temperature range, with minimums dropping to 3°C (37°F) and average highs around 32°C (89°F). This is a departure from August, where the temperatures typically range from a minimum of 7°C (46°F) and a higher average around 21°C (71°F), with maximums reaching 36°C (97°F). Additionally, September sees increased precipitation with 145 mm (5.7 in) over 12 days, compared to August's 103 mm (4.0 in) over 11 days. Humidity also rises slightly in September to 65%, compared to 60% in August. For more details, you can check the weather in August.

September showcases a wider range of temperatures with a minimum of 3°C and a maximum reaching up to 32°C, providing a warm average of 16°C. The month also experiences higher precipitation at 145 mm over 12 days, while humidity hovers at 65%. In contrast, October brings cooler conditions, with temperatures dipping as low as -1°C and an average of 11°C, peaking at 25°C. This month sees significantly less rainfall, totaling 69 mm over 9 days, and a rise in humidity to 84%. For more detailed insights on October weather, you can check weather in October.

September and November present contrasting weather patterns. In September, temperatures range from a comfortable 3°C (37°F) at night to a warm 32°C (89°F) during the day, with an average of 16°C (61°F). This month experiences about 145 mm (5.7 inches) of precipitation over 12 days, accompanied by a moderate humidity level of 65%. In comparison, November is considerably cooler, with temperatures dipping to a low of -5°C (23°F) and an average of only 6°C (43°F), peaking at 20°C (68°F). This month sees less precipitation at 87 mm (3.4 inches) spread over 10 days, but the humidity rises to a high of 89%. For a detailed look at the weather specifics, you can check weather in November.

In September, the weather is notably warmer and more variable, with temperatures ranging from a chilly 3°C (37°F) at night to a warm 32°C (89°F) during the day, and an average temperature of 16°C (61°F). The month experiences considerable rainfall, totaling 145 mm (5.7 in) over 12 days, and maintains a moderate humidity level of 65%. In contrast, December ushers in much colder conditions, with temperatures dipping as low as -9°C (15°F) and averaging only 2°C (36°F). The maximum temperature reaches a modest 16°C (62°F), and precipitation decreases to 71 mm (2.8 in) over 9 days, accompanied by a higher humidity of 89%. For a detailed overview of the weather conditions, take a look at the weather in December.

Compare 's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in

As September rolls in, Hajdina experiences a refreshing transition from the warmth of summer to the cooler embrace of autumn. With temperature variations that swing from the mild highs of 32°C to the crisp lows of 3°C, this month showcases a remarkable blend of warmth and coolness. Unlike the peak summer months, September welcomes an increased chance of rain, totaling 145 mm over approximately 12 days, paired with a humidity level around 65%, creating a more humid atmosphere. This harmonious mix of conditions transforms the landscape, making it an ideal time for nature lovers and adventurers alike to explore the beauty of the changing seasons. For more insights into the climate, visit Climate.