September Weather in Poznan, Poland

Last updated: August 27, 2025

September in Poznan, Poland, presents a charming blend of early autumn tranquility and lingering summer warmth. With maximum temperatures reaching up to 33°C (92°F), locals and visitors alike can still enjoy mild days before the chill settles in. The average temperature hovers around a comfortable 15°C (59°F), while the minimum drops to a brisk 3°C (37°F), inviting cozy evenings. This month also experiences an average precipitation of 59 mm (2.3 in) over about 10 days, contributing to a humidity level of 78%, adding a refreshing touch to the crisp air. Whether exploring historical sites or savoring local cuisine, September in Poznan is a delightful time for outdoor adventures and cultural experiences.

September Temperature in Poznan

In Poznan, Poland, September marks a delightful transition from the warmth of summer to the coolness of autumn. With minimum temperatures averaging around 3°C (37°F) and an inviting average of 15°C (59°F), the days are still pleasantly warm, reaching up to 33°C (92°F) during the peak. This month signals a gradual dip in temperatures, especially when compared to the heights of August, yet it retains a hint of summer’s lingering warmth. The crispness in the air and vibrant foliage emerging during this time hint at the seasonal shift, making September a captivating period for both locals and visitors to enjoy the beauty of Poznan's landscapes.

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

The chart illustrates September temperature patterns in Poznan, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Poznan, 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).
JanFebMarAprMayJunJulAugSepOctNovDec343540485667676859514336
Data source: Temperature data for Poznan generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Poznan

In September, Poznan experiences a noticeable transition as summer wanes, with precipitation amounting to 59 mm (2.3 in) across 10 rainy days. This total reflects a decline from the wetter months of July and August, yet remains significant compared to earlier in the year. As the changing season ushers in cooler weather, September's rainfall serves as a reminder of the approaching autumn, contributing to the lush landscapes that characterize the region. The steady precipitation pattern observed from May through October underscores Poznan's climate, with each month revealing its distinct character through varying rainfall levels and days of rain, hinting at the diverse beauty of the city throughout the year.

September Precipitation Trends in Poznan

The chart displays monthly precipitation patterns in Poznan, 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 Poznan, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec464443356869996359614047
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Poznan

In September, Poznan experiences a shift in humidity as it transitions from the summer to the autumn months. With humidity levels at 78%, it's notably drier than the sweltering summer months of June to August, which maintain a consistent 67%. This gradual drop hints at the cooling temperatures on the horizon, contrasting sharply with the winter months ahead, where humidity levels rise significantly again, peaking at 90% or more by January and February. Overall, September serves as a refreshing respite before the return of the damp conditions characteristic of the colder season, providing a perfect time for enjoying the crisp air without the oppressive moisture of summer.

September Average Humidity in Poznan

This chart illustrates the average monthly humidity levels in Poznan, 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 Poznan is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec91%90%87%81%67%67%67%67%78%84%89%92%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Poznan

As summer transitions to autumn in September, Poznan experiences a notable shift in UV Index levels, reflecting a high category rating of 6. This marks a decrease from the peak summer months of July and August, where the index rose to a very high 8. However, while sunburn potential remains, residents should be mindful with a burn time of just 25 minutes. As the days grow shorter and temperatures cool, the UV exposure still calls for vigilance, particularly during midday hours. For those seeking more detailed insights and forecasts, check out the full information on Poznan UV Index.

Maximum UV Index Levels in Poznan for September

The chart shows the monthly maximum UV Index (UVI) for Poznan 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 Poznan typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec124578876321
Data source: Poznan 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 Poznan

As September rolls into Poznan, Poland, the city enjoys a delightful average of 288 hours of sunshine, signaling the gentle transition from summer to autumn. This month, while slightly lower than the sun-drenched heights of June and July, still offers a rich tapestry of clear skies and warm days, making it an inviting time for outdoor activities. Following the peak of summer, September's rays are balanced—providing ample light, yet wrapped in the cool embrace of approaching fall. The gradual decline in sunshine hours from the summer's peak indicates a shift, as the city prepares for the shorter days of October, which offers only 241 hours of sunlight. This makes September an enchanting window to soak up the last whispers of summer while basking in the golden hues of early autumn.

Monthly Sunshine Duration in Poznan: September Highlighted

The September sunshine duration represents the total number of hours Poznan 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.
JanFebMarAprMayJunJulAugSepOctNovDec108h191h265h339h384h420h414h383h288h241h162h123h
Data source: Poznan September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Poznan During September

As summer transitions into autumn, September in Poznań, Poland, offers a 35% chance of sunny weather, mirroring the average conditions of April and July. This indicates a slight dip from the sunny heights of June, where the likelihood peaks at 50%. Interestingly, while the sunny days start to diminish as the month progresses, September remains a pleasant time to enjoy the last whispers of warmth before the chill of October sets in. The overall trend reflects a gradual decrease in sunshine as the year winds down, but with a September that still holds its own amidst the shifting seasons.

Percentage of Sunny Days in September in Poznan

The chart illustrates the percentage of sunny days in Poznan 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 Poznan experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec14%29%37%35%41%50%33%31%35%41%14%22%
Data source: Poznan September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Poznan in September

As summer fades into autumn, September in Poznan, Poland, offers a gentle transition with about 12 hours of daylight. After basking in the longest days of summer, where daylight peaked at 16 hours in June and July, the days begin to shorten, yet remain pleasantly bright. Following the vibrant months of May and June, which brought 15 to 16 hours of sunlight, September sees a modest decline, inviting a softer glow as nature prepares for the upcoming chill. This decrease in daylight serves as a reminder of the shifting seasons, with October bringing even shorter days of 10 hours. Embracing the lingering warmth and light, September is a beautiful bridge between the exuberance of summer and the cozy embrace of fall.

Average Daylight Hours in Poznan for September

The chart illustrates the variation in daylight duration in Poznan throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 16m9h 54m11h 54m13h 57m15h 45m16h 42m16h 12m14h 35m12h 36m10h 34m8h 43m7h 44m
Data source: Poznan daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Poznan

As September unfolds in Poznań, Poland, the average wind speed reaches a gentle 3.3 m/s (7 mph), not much different from the late summer winds of August. This mild breeze marks a subtle transition from the warmer months to the crispness of autumn. While the wind begins to pick up slightly in the following months—October averaging 3.9 m/s (9 mph) and November at 4.0 m/s (9 mph)—September offers a serene period where the air is still, hinting at the impending seasonal change without the harsher gusts of autumn yet to come. Overall, it’s a time when the city breathes a little easier, striking a balance between lingering warmth and the approach of cooler days.

Average September Wind Speed in Poznan

The chart displays monthly wind speed patterns in Poznan, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.43.43.53.63.72.82.93.23.3 m/s3.94.03.9
Data source: Poznan September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Poznan Compares to Other Months

Weather in Poznan varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Poznan, focusing on differences in temperature, rainfall, humidity, and UV levels.

September and January present starkly contrasting weather conditions. In September, temperatures range from a mild 3°C (37°F) at night to a warm average of 15°C (59°F) and even peak at a hot 33°C (92°F) during the day, accompanied by a reasonable level of humidity at 78%. The month experiences around 59 mm (2.3 inches) of precipitation over 10 days. In contrast, January brings a chilling drop, with nighttime lows plummeting to -18°C (1°F) and a chilly average of just 1°C (34°F), peaking at a modest 12°C (54°F). This winter month sees slightly less precipitation, totaling 46 mm (1.8 inches) over 11 days, but with an increased humidity of 90%, creating a damp and cold atmosphere. For more detailed information, you can refer to Poznan weather in January.

September and February present contrasting climates, with September enjoying warmer temperatures ranging from a mild 15°C (59°F) on average to highs of 33°C (92°F). This month witnesses a total of 59 mm (2.3 in) of precipitation over about 10 days, accompanied by a humidity level of 78%. In contrast, February is much colder, with temperatures averaging around 2°C (35°F) and reaching a maximum of only 17°C (63°F), while dipping as low as -15°C (5°F). With 44 mm (1.7 in) of precipitation spread over 9 days and a higher humidity level of 90%, February's weather is more frigid and damp. To learn more about the specifics of February weather, you can visit Poznan weather in February.

In comparing September and March weather, September boasts a notable warmth with average temperatures around 15°C (59°F) and maximums reaching up to 33°C (92°F), while March presents a much chillier profile, with average temperatures of just 4°C (40°F) and lows that can plummet to -14°C (6°F). Precipitation levels are relatively close, with September receiving 59 mm (2.3 in) over 10 days, compared to March's 43 mm (1.7 in) spread over 11 days. Additionally, March has a higher humidity level at 87%, making the air feel brisker in contrast to September's 78%. For more details, you can check Poznan weather in March.

September and April showcase distinct weather patterns, reflecting the transition into autumn and the arrival of spring, respectively. In September, temperatures range widely from a chilly 3°C (37°F) to a warm 33°C (92°F), with an average temperature of 15°C (59°F). This month experiences around 59 mm (2.3 in) of precipitation over approximately 10 days, along with a humidity level of 78%. In contrast, April sees cooler temperatures, with a minimum of -3°C (26°F) and a maximum of 27°C (81°F), averaging around 9°C (48°F). The rainfall in April is lighter, totaling 34 mm (1.4 in) across 9 days and a slightly higher humidity level of 80%. For more detailed insights into weather patterns in April, check out Poznan weather in April.

The weather in September is generally warmer compared to May, with average temperatures reaching 15°C (59°F) and maximum highs of 33°C (92°F). In contrast, May sees an average temperature of 13°C (56°F) and a maximum of 30°C (86°F). September tends to be more humid, averaging 78% compared to May's 67%. While both months experience similar amounts of precipitation, September has slightly less at 59 mm (2.3 in) over approximately 10 days compared to May's 68 mm (2.7 in) over 11 days. For more details on May's weather, you can refer to Poznan weather in May.

In comparing the weather of September and June, we notice some notable differences. September typically experiences a wider temperature range, with minimum temperatures dropping to 3°C (37°F) and maximums reaching 33°C (92°F), leading to an average of 15°C (59°F). In contrast, June has slightly warmer minimum temperatures at 4°C (40°F) and a higher average of 19°C (67°F), with maximums potentially soaring up to 37°C (98°F). Both months see a similar level of precipitation, with September recording 59 mm (2.3 in) over about 10 days and June slightly higher at 69 mm (2.7 in) across 11 days, though June benefits from lower humidity at 67% compared to September’s 78%. For more detailed insights into June specifically, you can visit Poznan weather in June.

When comparing the weather in September to that of July, noticeable differences emerge. July tends to be warmer, with average temperatures reaching 19°C (67°F) and maximums soaring up to 37°C (99°F). In contrast, September presents a more moderate climate, offering minimums of 3°C (37°F) and averages of 15°C (59°F). Precipitation levels are also higher in July, with 99 mm (3.9 in) over 12 days, compared to September's 59 mm (2.3 in) spread over 10 days. Additionally, July has lower humidity at 67%, while September's humidity rises to 78%, contributing to a different feel during those months. For more details, you can check Poznan weather in July.

In comparing the weather of September and August, September features a slightly cooler temperature range, with minimums of 3°C (37°F) compared to August's 6°C (43°F). The average temperature in September is also lower at 15°C (59°F), whereas August enjoys a warmer average of 20°C (68°F). However, both months have similar maximum temperatures, with September reaching up to 33°C (92°F) and August peaking at 34°C (93°F). Precipitation levels are comparable, with September receiving 59 mm (2.3 in) of rain over 10 days, just slightly less than August's 63 mm (2.5 in) across the same number of days. Notably, September has a higher humidity level at 78%, compared to August’s 67%. For those looking for more details about August weather, check out Poznan weather in August.

September weather in Poznan is characterized by warmer temperatures, with a minimum of 3°C (37°F) and a maximum reaching up to 33°C (92°F). The average temperature hovers around a comfortable 15°C (59°F), and while there is a significant amount of humidity at 78%, the precipitation is relatively moderate at 59 mm over 10 days.

In contrast, October sees a notable drop in temperatures, with minimums plunging to -3°C (27°F) and a maximum of 24°C (76°F). The average temperature for the month is cooler at 11°C (52°F), and while the precipitation slightly increases to 61 mm over 11 days, humidity rises to 84%. This shift marks a transition into the chillier autumn days. For more detailed information, you can check Poznan weather in October.

September and November present quite a contrast in weather. In September, temperatures are much warmer, with an average of 15°C (59°F) and highs reaching up to 33°C (92°F), making it feel more like the tail end of summer. With 59 mm (2.3 in) of precipitation spread over about 10 days, humidity levels sit at 78%, giving the month a muggy feel. In stark contrast, November brings a noticeable chill, with average temperatures dropping to 6°C (43°F) and lows dipping to -5°C (23°F). Although it has less rainfall at 40 mm (1.6 in) over 8 days, humidity increases to 89%, making the air feel crisp and damp. For more detailed information, check out Poznan weather in November.

September and December showcase a dramatic shift in weather conditions. In September, temperatures range from a pleasant minimum of 3°C (37°F) to a warm maximum of 33°C (92°F), with an average of 15°C (59°F) and relatively high humidity at 78%. The month sees about 59 mm (2.3 inches) of precipitation over approximately 10 days. In contrast, December plunges into winter, with temperatures dropping significantly, featuring a minimum of -17°C (2°F) and a maximum of only 12°C (55°F), resulting in an average temperature of just 2°C (36°F). Although precipitation decreases to 47 mm (1.8 inches) over 11 days, humidity rises to 92%, contributing to a chilly, damp atmosphere. For more detailed information, check out Poznan weather in December.

Compare Poznan's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Poznan

September in Poznan marks a transitional phase, where the lingering warmth of summer begins to give way to the crispness of autumn. The temperature range showcases a delightful mix, with days that can still reach a balmy warmth juxtaposed against cooler nights. While the humidity remains relatively high, bringing about a certain softness to the air, the month sees a moderate amount of rainfall that can occasionally disrupt plans. This unique blend of weather creates an inviting atmosphere, perfect for enjoying outdoor activities while the foliage starts to change. For more in-depth insights about the climate of Poznan, check out Poznan Climate.