Last updated: August 27, 2025
September in Piran, Slovenia, showcases a delightful transition into autumn, with maximum temperatures soaring to a pleasant 28°C (82°F) and an average of 22°C (71°F), providing a warm backdrop for outdoor activities. Nights cool off with a minimum of 14°C (57°F), perfect for cozy evenings. While the region experiences 10 days of precipitation, totaling 171 mm (6.7 in), the average humidity remains at a comfortable 64%. This blend of warmth and occasional rain creates an inviting atmosphere, making September an ideal time to explore Piran's charming coastal landscapes.
In September, Piran, Slovenia, experiences a delightful transition as summer gradually gives way to autumn. With minimum temperatures around 14°C (57°F) and soaring to a pleasant maximum of 28°C (82°F), the month boasts an average of 22°C (71°F), making it one of the most enjoyable times to visit. As the air begins to cool, the days remain warm and inviting, perfect for exploring the stunning coastal scenery or indulging in local cuisine. This month reflects a noteworthy trend, showcasing a balance of warmth and crispness that hints at the forthcoming seasonal change, all while inviting visitors to bask in the lingering summer sun before the cooler months set in.
September marks a notable shift in precipitation patterns in Piran, Slovenia, as the month experiences a significant uptick in rainfall, totaling 171 mm (6.7 in) over 10 days. This surge contrasts sharply with the summer months, where precipitation was relatively low, peaking at 58 mm (2.3 in) in both August and July. As summer's dry spell fades, September’s rain sets the stage for the autumn months, which maintain high levels of moisture, particularly witnessing November's impressive 183 mm (7.2 in). Overall, this transition highlights September as a pivotal month where the area's lush landscapes are rejuvenated, paving the way for the rich colors of fall.
In September, Piran experiences a moderate humidity level of 64%, a slight uptick from the drier summer months of July and August, where humidity dipped to 63% and 51%, respectively. This increase signals the transition from the warmth of summer to the more humid conditions that autumn brings, as indicated by the significant rise to 83% in October. The overall trend from January to September shows a gradual decrease in humidity, peaking in the colder months, with January and February showcasing the highest levels at 88% and 82%. As nature shifts gears, September serves as a gentle reminder of the approaching fall, blending the lingering warmth of summer with the onset of a wetter season.
As summer transitions into autumn, Piran, Slovenia experiences a notable decrease in the UV Index, with September boasting a UV Index of 7, categorized as high. This indicates a gradual shift from the intense summer sun, where values peaked at 9 in June and July, requiring only 15 minutes for potential skin damage. In contrast, September allows for a more moderate burn time of 25 minutes, making it a favorable month for outdoor activities while still necessitating precautions. This trend reflects the seasonal changes, with UV exposure beginning to decline toward the more moderate indices seen in October and November. For those looking to stay informed about the UV levels throughout the year, visit Piran UV Index.
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September in Piran, Slovenia is a delightful blend of summer warmth and early autumn charm, boasting 326 hours of sunshine. As the days gradually shorten, this month reflects a soft transition from the sun-drenched heights of July, which stands at 430 hours, to the more subdued glow of October with 293 hours. The sunshine peaks in the summer months, but September retains a significant share, making it an ideal time for visitors to enjoy the picturesque coastal city with pleasant weather and fewer crowds. With the sun still shining brightly, this month invites leisurely strolls along the waterfront and exploration of the charming old town, allowing both locals and tourists to bask in the fading summer rays before autumn takes hold.
As summer transitions into autumn, September in Piran, Slovenia presents a fairly promising chance of sunny weather, with about 59% likelihood of sunshine. This marks a slight decline from the sun-drenched days of August, which boasts a 62% chance. While the sunny days diminish as the year progresses, the overall trend from earlier months shows that September still holds onto a respectable amount of bright weather compared to the rest of the year. With a higher chance of sun than many of the preceding and following months, including the likes of October and November, September remains an alluring time for those seeking pleasant days in this charming coastal town.
As summer wanes, September in Piran, Slovenia marks a gentle transition, with daylight lasting approximately 12 hours. This decrease from the sun-soaked days of July and August, which enjoy 15 and 14 hours of sunlight respectively, hints at the inevitable approach of autumn. While the days begin to shorten, September still radiates warmth and brightness, providing a perfect backdrop for outdoor adventures. As nature prepares for the cooler months, the gradual decline in daylight invites a cozy atmosphere, making it an ideal time for reflection and connection in this charming coastal town.
As summer transitions to autumn in Piran, September brings a gentle breeze with an average wind speed of 3.4 m/s (8 mph). This is slightly lower than the lively gusts of May and April, which average around 4.1 to 4.5 m/s, yet it maintains a serene atmosphere perfect for leisurely strolls along the Adriatic coast. Throughout the year, the wind tends to fluctuate, peaking in the late autumn months of October (5.0 m/s) and November (5.2 m/s), suggesting that the city's maritime charm is heightened as the seasons change. The mild winds of September, while less vigorous, create an inviting backdrop for both locals and visitors to savor the lingering warmth before winter sets in.
Weather in Piran varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Piran, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January showcase contrasting weather patterns. In September, temperatures range from a minimum of 14°C (57°F) to a maximum of 28°C (82°F), with an average of 22°C (71°F). The month experiences significant rainfall, totaling 171 mm (6.7 in) over approximately 10 days, coupled with a moderate humidity level of 64%. In sharp contrast, January brings much colder conditions, with temperatures dipping to a minimum of -3°C (27°F) and peaking at 13°C (56°F), averaging around 7°C (46°F). Additionally, January sees less precipitation—58 mm (2.3 in) over 7 days—and higher humidity at 88%. For more details, check out Piran weather in January.
September and February exhibit stark contrasts in weather conditions. September enjoys milder temperatures, with averages around 22°C (71°F) and highs reaching 28°C (82°F), whereas February experiences much colder weather, with averages plummeting to just 8°C (47°F) and maximums only peaking at 13°C (56°F). In terms of precipitation, September has more rainfall, recording 171 mm (6.7 in) over about 10 days, compared to February's 106 mm (4.2 in) across 11 days. Additionally, February exhibits higher humidity levels at 82%, further emphasizing the chilly and damp atmosphere. For more detailed insights into February weather, check this link: Piran weather in February.
In comparing the weather of September and March, one can observe notable differences in temperature and precipitation. September typically experiences milder conditions with average temperatures ranging from a minimum of 14°C (57°F) to a maximum of 28°C (82°F), and a decent amount of rainfall totaling 171 mm (6.7 in) over about 10 days, coupled with a relative humidity of 64%. In contrast, March is much cooler, with average temperatures ranging from a minimum of -3°C (27°F) to a maximum of 16°C (62°F). This month sees significantly less precipitation at 57 mm (2.3 in) over approximately 7 days, although humidity is slightly higher at 73%. For more detailed insights into March weather, you can check Piran weather in March.
September typically experiences warmer temperatures compared to April, with minimums around 14°C (57°F) and maximums reaching 28°C (82°F), whereas April sees lower temperatures ranging from a minimum of 5°C (42°F) to a maximum of 20°C (68°F). Additionally, September tends to be wetter, averaging 171 mm (6.7 in) of precipitation over 10 days, while April has significantly less at 86 mm (3.4 in) over 8 days. Despite its lower temperatures, April has a higher humidity level of 73%, compared to September's 64%. For more detailed information about weather conditions in Piran during April, visit Piran weather in April.
September and May present distinct weather patterns. In September, temperatures are generally warmer, with a minimum of 14°C (57°F) and averaging around 22°C (71°F), peaking at 28°C (82°F). However, it also experiences higher precipitation, totaling 171 mm (6.7 in) over about 10 days, and a humidity level of 64%. In contrast, May is cooler, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 24°C (76°F) and an average of 17°C (64°F). While it sees slightly less rainfall at 105 mm (4.2 in) over 13 days, the humidity is higher at 70%. For more details on May weather, you can check this link: Piran weather in May.
In comparing the weather of September and June, we find that September typically has slightly cooler temperatures, with a minimum of 14°C (57°F) and an average around 22°C (71°F), while June starts off warmer, registering a minimum of 16°C (61°F) and an average of 23°C (73°F). The maximum temperatures in June can reach up to 30°C (86°F), compared to September's peak of 28°C (82°F). Precipitation also varies significantly; September experiences a much wetter climate with 171 mm (6.7 in) over approximately 10 days, while June is drier, with only 68 mm (2.7 in) over about 5 days. Additionally, humidity levels are relatively high in both months, with September at 64% and June at 69%. For more detailed insights, you can check Piran weather in June.
When comparing the weather in September and July, it’s evident that July tends to be warmer overall. In July, temperatures range from a minimum of 20°C (68°F) to a maximum of 29°C (85°F), with an average of 25°C (77°F). In contrast, September sees cooler temperatures, with a minimum of 14°C (57°F) and a maximum of 28°C (82°F), averaging 22°C (71°F). Additionally, September experiences significantly more precipitation, measuring 171 mm (6.7 in) over approximately 10 days, compared to the 49 mm (1.9 in) over 6 days in July. Both months have similar humidity levels, with September at 64% and July at 63%. For more detailed weather information, you can check Piran weather in July.
In comparing the weather patterns of September and August, September tends to showcase cooler temperatures, with a minimum of 14°C (57°F) and an average of 22°C (71°F), whereas August is warmer with a minimum of 17°C (63°F) and an average of 26°C (78°F). The maximum temperatures also reflect this trend, peaking at 28°C (82°F) in September compared to 30°C (87°F) in August. Additionally, September experiences significantly higher precipitation, totaling 171 mm (6.7 in) over 10 days, while August records only 58 mm (2.3 in) over 6 days. Overall, September is cooler and wetter, exhibiting a humidity level of 64%, compared to August's lower humidity of 51%. For a detailed look at August weather, see Piran weather in August.
September and October present notable contrasts in weather. September enjoys a warmer average temperature of 22°C (71°F), with maximums reaching 28°C (82°F), while October sees cooler averages around 17°C (64°F) and maximums peaking at 23°C (73°F). Precipitation is also more abundant in September, totaling 171 mm (6.7 in) across 10 days, compared to October’s 100 mm (4.0 in) over the same number of days. Additionally, humidity rises from 64% in September to 83% in October, contributing to a more muggy feel as autumn progresses. For more specifics, you can check out Piran weather in October.
September and November present contrasting weather patterns. In September, temperatures range from a mild minimum of 14°C (57°F) to a warm maximum of 28°C (82°F), with an average of 22°C (71°F). The month experiences about 171 mm (6.7 in) of precipitation over 10 days, accompanied by a humidity level of 64%. In contrast, November sees a significant drop in temperatures, with minimums around 6°C (42°F) and a maximum of 19°C (67°F), resulting in an average temperature of only 13°C (56°F). The month is slightly wetter, with 183 mm (7.2 in) of rainfall spread over 13 days, while humidity increases to a notable 89%. For more details, you can check Piran weather in November.
September and December present quite contrasting weather patterns. In September, temperatures are generally milder, with a minimum of 14°C (57°F) and an average of 22°C (71°F), peaking at 28°C (82°F). Although the month sees significant rainfall with 171 mm (6.7 in) over about 10 days, humidity remains relatively comfortable at 64%. In contrast, December experiences much cooler temperatures, with a minimum of 4°C (39°F) and an average of just 10°C (50°F), reaching a maximum of 16°C (60°F). Precipitation is slightly lower at 150 mm (5.9 in), but occurs over more days, totaling 13. The humidity also increases to a notable 88%, making December feel much damper and cooler. For more detailed insights, check out Piran weather in December.
September in Piran offers a delightful transition from the heat of summer to the cooler embrace of fall, characterized by warm days and pleasantly mild evenings. While the average temperature provides a comfortable climate for outdoor activities, the increased precipitation signals the onset of autumnal changes. This month stands out from others as humidity remains notably high, creating a unique atmosphere alongside the scenic coastal views. Perfect for exploring the city’s rich history or enjoying its beautiful beaches before the chill of winter sets in, September truly showcases Piran's diverse climate. For more details on what to expect throughout the year, check out Piran Climate.