September Weather in Bologna, Italy

Last updated: March 24, 2025

Bologna in September features a rich tapestry of weather, with maximum temperatures soaring up to 34°C (93°F), providing plenty of warmth for outdoor exploration. On average, temperatures hover around a comfortable 21°C (70°F), perfect for enjoying the city’s vibrant culture. However, the month also sees cooler nights, with lows dipping to 7°C (45°F), so a light jacket may be necessary. Rainfall amounts to 86 mm (3.4 in) over approximately 10 days, contributing to the area’s lush landscapes. With a humidity level of 66%, visitors can expect a pleasantly warm climate, ideal for wandering through Bologna's historic streets while savoring local cuisine.

September Temperature in Bologna

In September, Bologna basks in the lingering warmth of summer, with temperatures gradually transitioning into the crispness of autumn. The average temperature settles at a comfortable 21°C (70°F), while daytime highs can reach an inviting 34°C (93°F), making it an ideal time for outdoor exploration. As the month progresses, evening temperatures cool down, dipping to a refreshing 7°C (45°F), perfect for enjoying the city's famed al fresco dining. This blend of warm days and cooler nights sets the stage for a delightful experience, whether you’re wandering through historic streets or savoring local cuisine. The clear skies and pleasant climate make September a prime time to immerse yourself in the vibrant culture of Bologna before the chill of autumn truly takes hold.

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

The chart illustrates September temperature patterns in Bologna, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec394549576575797969605042
Data source: Temperature data for Bologna 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 Bologna

September in Bologna marks a notable transition in weather as the summer heat begins to fade, bringing an increase in precipitation. With 86 mm (3.4 inches) of rain recorded over 10 days, this month stands out as one of the wetter times of the year. This uptick follows a relatively dry August and sets the stage for the wetter months ahead, particularly November, which averages 118 mm (4.6 inches) of rain. The shift not only revitalizes the landscape but also signals the gradual approach of autumn, making September a month of refreshing change in the Emilia-Romagna capital.

September Precipitation Trends in Bologna

The chart displays monthly precipitation patterns in Bologna, 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.
JanFebMarAprMayJunJulAugSepOctNovDec24734859112486049866511874
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Bologna

As summer turns to autumn, September in Bologna brings a noticeable shift in humidity, settling at 66%. This marks a slight increase from the drier months of July and August, which saw the lowest levels at 61% and 54%, respectively. The gradual rise in humidity hints at the approach of the rainy season, with October expected to see a significant jump to 83%. Overall, the trend reveals a steady decline in humidity from the start of the year, peaking towards winter as the colder months draw nearer. September serves as a gentle reminder of the changing seasons, balancing the lingering warmth of summer with the impending chill of autumn.

September Average Humidity in Bologna

This chart illustrates the average monthly humidity levels in Bologna, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec87%79%69%71%70%65%61%54%66%83%88%85%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Bologna

As September unfolds in Bologna, Italy, the UV Index settles at a moderate level of 7, indicating a transition from the heights of summer. After the peak UV exposure in July and August, with values of 9 and 8 respectively, this month offers slightly more protection while still calling for caution during outdoor activities. With a burn time of 25 minutes, it's a reminder that while the summer heat begins to wane, harmful UV rays remain a concern. As autumn approaches, maintaining awareness of UV levels is crucial in striking a balance between enjoying the pleasant weather and protecting your skin. For more details, check out the Bologna UV Index.

Maximum UV Index Levels in Bologna for September

The chart shows the monthly maximum UV Index (UVI) for Bologna 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.
JanFebMarAprMayJunJulAugSepOctNovDec2367810987532
Data source: Bologna 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 Bologna

September in Bologna brings a delightful transition, with 336 hours of sunshine that echo the warm embrace of summer while hinting at the approach of autumn. After a peak in July with 427 hours, the days begin to taper just slightly, yet September’s glow remains generous compared to earlier months. In fact, it boasts more sun than any month from November through May, offering a vibrant backdrop for leisurely strolls through the city's historic streets. As the sun sets earlier, the warmth of September sun invites both locals and tourists to savor the rich flavors of Bologna’s culinary scene in the golden twilight, making it a perfect time to unwind before the cooler months arrive.

Monthly Sunshine Duration in Bologna: September Highlighted

The September sunshine duration represents the total number of hours Bologna 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.
JanFebMarAprMayJunJulAugSepOctNovDec180h220h310h339h381h419h427h397h336h297h209h211h
Data source: Bologna September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Bologna During September

In Bologna, Italy, September ushers in a refreshing transition from the sweltering summer months, providing a 55% chance of sunny weather. This likelihood is a modest drop from August's 62% but remains favorable compared to the earlier spring months. As the city moves from the high summer sunshine of July and August, the chance of sun in September still offers ample opportunities for outdoor exploration. Notably, this percentage marks a noteworthy improvement over the cooler months of October and November, creating a delightful window for both locals and tourists to enjoy Bologna's rich cultural tapestry under pleasant skies. Overall, September stands out as an excellent choice for those seeking sunny days amidst the backdrop of the city's stunning architecture and vibrant atmosphere.

Percentage of Sunny Days in September in Bologna

The chart illustrates the percentage of sunny days in Bologna 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 Bologna experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec37%46%69%47%48%60%54%62%55%46%30%45%
Data source: Bologna September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Bologna in September

As summer transitions into autumn, September in Bologna, Italy, presents a gentle shift in daylight duration, offering about 12 hours of sunshine. Following the peak of daylight in June and July, which bask in a full 15 hours, September celebrates a comforting reduction, embracing a balance between the sun's lingering warmth and the crispness of fall. This month marks the beginning of a gradual descent in daylight, reflecting the changing seasons as it dips to 10 hours by October. The progression from the lively 14 hours of May highlights a seasonal rhythm, where each month dances along the spectrum of sunlight, inviting residents and visitors alike to relish the last hints of summer before embracing the cozy embrace of autumn.

Average Daylight Hours in Bologna for September

The chart illustrates the variation in daylight duration in Bologna throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 14m10h 26m11h 56m13h 29m14h 48m15h 28m15h 7m13h 57m12h 28m10h 56m9h 34m8h 52m
Data source: Bologna daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Bologna

As summer gracefully transitions into fall, September in Bologna experiences a noticeable dip in average wind speed, reaching a gentle 1.7 m/s (4 mph). This marks one of the calmest months of the year, as the bustling city shifts from the warm embrace of summer to the cooler whispers of autumn. Following the summer months that showcased slightly stronger breezes, September's tranquil winds create an inviting atmosphere, perfect for leisurely strolls through the historic streets. This decline in wind speed not only highlights the seasonal change but also enhances the charm of Bologna, making it a delightful time for visitors to soak in the rich culture and vibrant landscapes in a serene setting.

Average September Wind Speed in Bologna

The chart displays monthly wind speed patterns in Bologna, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.12.02.12.22.62.01.92.21.7 m/s2.12.01.6
Data source: Bologna September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Bologna Compares to Other Months

The weather in Bologna changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Bologna and find detailed weather information for every month.

September and January present starkly contrasting weather conditions. In September, temperatures range from a minimum of 7°C (45°F) to a peak of 34°C (93°F), accompanied by an average of 21°C (70°F). This month typically experiences 86 mm (3.4 in) of precipitation over about 10 days, with humidity levels around 66%. In contrast, January is much cooler, with temperatures ranging from a minimum of -6°C (22°F) to a maximum of only 15°C (59°F) and an average of 4°C (39°F). Precipitation during this month is significantly lower at 24 mm (1.0 in) over approximately 4 days, and the humidity rises to 87%. For more detailed information, you can check Bologna weather in January.

September and February present strikingly different weather patterns. In September, temperatures range from a mild 7°C (45°F) to a warm maximum of 34°C (93°F), with an average of 21°C (70°F). The month experiences about 86 mm (3.4 in) of precipitation over approximately 10 days, accompanied by a moderate humidity level of 66%. In contrast, February is characterized by much colder conditions, with temperatures dipping as low as -9°C (16°F) and reaching a maximum of 21°C (70°F), while the average temperature is only around 7°C (45°F). Precipitation in February totals 73 mm (2.9 in) over 9 days, and the humidity is slightly higher at 79%. For a closer look at the weather specifics in February, you can check Bologna weather in February.

When comparing the weather between September and March, there are notable differences in temperature and precipitation. September enjoys a warm average temperature of 21°C (70°F), peaking at 34°C (93°F), while March is considerably cooler, with an average of only 10°C (50°F) and a maximum of 25°C (77°F). Precipitation in September is higher, with 86 mm (3.4 in) over about 10 days compared to March’s 48 mm (1.9 in) across 7 days. Interestingly, both months have similar humidity levels, with September at 66% and March at 69%. For those looking for more detailed information, check out Bologna weather in March.

In comparing the weather between September and April, a marked contrast in temperatures is evident. September boasts milder conditions, with average temperatures reaching a comfortable 21°C (70°F) and maximums soaring to 34°C (93°F). In contrast, April's temperatures are cooler, with an average of 14°C (57°F) and nighttime lows dipping as low as -1°C (31°F). While September experiences more precipitation, totaling 86 mm (3.4 in) over about 10 days, April sees slightly less, with 59 mm (2.3 in) falling over 8 days. Interestingly, April has a higher humidity level at 71%, compared to September's 66%. For those looking to explore the weather patterns in April specifically, more details can be found here: Bologna weather in April.

In September, the weather is generally warmer, with average temperatures around 21°C (70°F) and maximums reaching up to 34°C (93°F). In contrast, May sees slightly cooler temperatures, averaging 18°C (65°F) and peaking at 32°C (90°F). Both months experience notable humidity levels, with September at 66% and May slightly higher at 70%. Rainfall is also more frequent in May, with 112 mm (4.4 in) over 14 days, compared to September's 86 mm (3.4 in) over 10 days. For a detailed look at May's climate, check out Bologna weather in May.

In comparing the weather between September and June, September features a wider temperature range, with minimums dipping to 7°C (45°F) and maximums reaching 34°C (93°F). In contrast, June offers warmer conditions, with a minimum of 12°C (55°F) and maximums soaring to 39°C (102°F), making it the hotter month overall. While September experiences more precipitation, totaling 86 mm (3.4 in) over approximately 10 days, June is relatively drier with only 48 mm (1.9 in) over 7 days. Humidity levels are quite similar, with September at 66% and June slightly lower at 65%. For detailed insights into June's weather patterns, you can check Bologna weather in June.

In comparing the weather of September to that of July, it's clear that September experiences a wider temperature range, with minimums dipping to 7°C (45°F) and maximums reaching up to 34°C (93°F). In contrast, July presents a warmer profile, with minimum temperatures averaging 15°C (60°F) and soaring to a maximum of 38°C (100°F). Precipitation in September is slightly higher, totaling 86 mm (3.4 in) over 10 days, compared to July's 60 mm (2.3 in) over 8 days. Additionally, September sees a higher humidity level at 66%, while July maintains a lower humidity of 61%. For more specific information, you can check out Bologna weather in July.

In comparing the weather between August and September, September tends to be cooler, with average temperatures ranging from a minimum of 7°C (45°F) to a maximum of 34°C (93°F), while August boasts warmer averages between 13°C (55°F) and 40°C (105°F). Although September sees a slightly higher amount of precipitation at 86 mm (3.4 in) over 10 days compared to August's 49 mm (1.9 in) over 8 days, the humidity is notably higher in September at 66%, compared to 54% in August. For more detailed insights, you can refer to Bologna weather in August.

In September, the weather typically features warmer temperatures, with averages around 21°C (70°F) and maximums reaching as high as 34°C (93°F). This month experiences a total precipitation of 86 mm (3.4 in) over about 10 days, alongside a humidity level of 66%. In contrast, October sees a significant drop in temperature, averaging 15°C (60°F) and peaking at 27°C (82°F). The precipitation decreases to 65 mm (2.5 in) over roughly 7 days, but humidity rises to a higher average of 83%. For more specific details about weather patterns in this month, you can check Bologna weather in October.

September weather is typically warm and variable, with temperatures ranging from a minimum of 7°C (45°F) to a maximum of 34°C (93°F), and an average temperature of 21°C (70°F). This month sees approximately 86 mm (3.4 in) of precipitation over 10 days, coupled with a humidity level of 66%. In contrast, November brings a significant drop in temperatures, with a range from -2°C (29°F) to 20°C (68°F), averaging just 10°C (51°F). Rainfall increases to 118 mm (4.6 in) over 12 days, and humidity rises to a more pronounced 88%. For more details, you can check Bologna weather in November.

September and December present starkly different weather patterns. September typically enjoys milder temperatures, ranging from a minimum of 7°C (45°F) to a maximum of 34°C (93°F), with an average of 21°C (70°F). This month also sees considerable rainfall, with precipitation reaching 86 mm (3.4 in) over about 10 days, contributing to a moderate humidity of 66%. In contrast, December experiences much colder weather, with temperatures dropping to a minimum of -6°C (22°F) and an average of only 5°C (42°F). The maximum temperature during this month reaches just 16°C (61°F), and while precipitation decreases slightly to 74 mm (2.9 in), the humidity increases to 85%. For more detailed insights on December weather, you can explore this link: Bologna weather in December.

Compare Bologna's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Bologna

As summer fades, September in Bologna presents a delightful transition marked by warm days and cool evenings. With average temperatures hovering around a comfortable 21°C (70°F), this month invites outdoor exploration, though visitors should be prepared for occasional rain, as approximately 10 days bring 86 mm (3.4 in) of precipitation. The humidity at 66% adds a touch of summer's lingering warmth, creating a vibrant atmosphere that differs significantly from the sweltering heights of July and August. This is an ideal time to enjoy the rich cultural experiences Bologna offers, all against a backdrop of shifting colors and changing seasons. For more insights, check out Bologna Climate.