Last updated: August 27, 2025
September in Saint Petersburg, Russian Federation, offers a captivating blend of early autumn charm and climatic variability. The temperature swings from a maximum of 24°C (76°F) to a brisk minimum of 1°C (34°F), with an average hovering around 12°C (54°F). This month marks a transitional phase, where lush greenery begins to give way to vibrant hues of fall. Rainfall is frequent, totaling 76 mm (3.0 in) across 14 days, contributing to the city’s renowned humidity levels, which linger around 90%. Visitors can experience the unique beauty of Saint Petersburg as it dons its autumn attire, making September a month of both brisk weather and scenic allure.
As summer fades into autumn, September in Saint Petersburg, Russian Federation, presents a notable shift in temperatures, marking the transition from the warmth of summer to the crispness of fall. With minimums dipping to 1°C (34°F) and an average around 12°C (54°F), the city starts to cool down significantly compared to the preceding months. The highs can reach a comfortable 24°C (76°F), offering a pleasant atmosphere for exploring before the chill of October sets in. This month reflects a beautiful balance, where the lingering warmth from summer blends with the fresh air of approaching autumn, making it a captivating time to experience the city's rich culture and stunning architecture.
In September, Saint Petersburg experiences a notable transition as the summer warmth begins to wane, accompanied by a precipitation total of 76 mm (3.0 in) over 14 days. This amount marks a slight decrease from the wetter months of July and August, where rainfall peaked at 82 mm (3.2 in) and 115 mm (4.5 in), respectively. However, September's precipitation remains significant, continuing the trend of frequent rain typical for the city in the early autumn. As the days grow shorter and cooler, the moderate rainfall sets a picturesque scene, blending the charm of the city's historic architecture with the soft, overcast skies that often prevail during this season.
In September, the humidity in Saint Petersburg stands at a notable 90%, marking a slight increase from the summer months. This uptick signifies the gradual transition from the relatively warmer, more humid days of July and August to the cooler embrace of autumn. Notably, the humidity has a downward trend from the peak summer levels, dipping from 86% in August, but it still remains significantly high compared to the drier late spring months, such as May, which recorded 74%. As autumn approaches, the humidity levels begin to rise again, resembling January's lofty 97%, suggesting that the city's climate retains a characteristic dampness even as the seasons change.
As September settles in Saint Petersburg, the UV Index dips to 4, indicating a moderate exposure category. This slight decrease from the summer highs reflects a transition toward cooler autumn days, but it's still essential to stay mindful of sun exposure, as the burn time remains at 30 minutes. Following the peak summer months, where the UV Index reached 7, September marks a gradual decline, yet the sun can still be deceptively potent. Embrace the pleasant early autumn weather while taking precautions to protect your skin. For more detailed information, visit Saint Petersburg UV Index.
UV Risk Categories
As September unfolds in Saint Petersburg, residents can bask in a generous 280 hours of sunshine, a delightful transition from the vibrant summer months. This substantial amount of sunlight reflects the peak of the city's annual solar gain, following June's impressive high of 469 hours. While the sunlight gradually diminishes as autumn approaches, with October bringing only 189 hours, September stands resilient as a bridge between the golden rays of summer and the fading light of winter. The trend of gradually decreasing sunshine from the sun-drenched months of May through August culminates in September's warm glow, inviting all to embrace the lingering warmth before the colder months settle in.
In September, the promise of sunny weather in Saint Petersburg begins to wane, with a sunshine probability of only 21%. This marks a noticeable decline from the peak months of July and June, where the chance for sun reaches 57% and 56%, respectively. As summer retreats, and the days grow shorter, residents and visitors alike may find themselves yearning for those bright, warm rays. Despite the dip in sunshine, September still offers more favorable weather compared to the onset of autumn and the stark chill of the following months. With October nudging back up to 34%, the transition into fall provides a unique opportunity to enjoy the lingering beauty of early autumn light.
In Saint Petersburg, September marks a gentle transition from the long, sunlit days of summer to the shorter daylight hours of autumn. With approximately 12 hours of daylight, the month showcases a decline from the 17 hours in May and 18 hours in June, yet it still affords ample time to enjoy the city's vibrant parks and historic sites. As the season shifts, the days gradually shorten, paving the way for the dimmer months ahead. This gradual decrease is a notable trend, reflecting the city's unique latitude and the distinct seasonal rhythms that frame the cultural backdrop of this beautiful Russian city. As September unfolds, residents and visitors alike embrace the lingering warmth while anticipating the changing colors of fall.
As September unfolds in Saint Petersburg, the city experiences a notable shift in its wind patterns, with an average wind speed of 4.4 m/s (10 mph), a touch gentler than the gusty October that follows. This slight decrease in speed, compared to the breezy August, heralds the beginning of autumn, as the winds transition from the lively bursts of summer to a more subdued yet refreshing crispness. Tracking the year, one can see that the wind speeds increase steadily from March’s 4.8 m/s (11 mph), peaking in October at 5.3 m/s (12 mph), indicating a seasonal trend where the breezes grow stronger as the year progresses. By the time November arrives, the winds kick up further, averaging 5.4 m/s (12 mph), suggesting that this rhythmic dance of air is a harbinger of the colder months ahead.
Weather in Saint Petersburg varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Saint Petersburg, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present contrasting weather conditions, reflecting the transition from late summer to winter. In September, temperatures range from a minimum of 1°C (34°F) to a maximum of 24°C (76°F), with an average temperature of 12°C (54°F). The month experiences substantial precipitation totaling 76 mm (3.0 in) over approximately 14 days, alongside a humidity level of 90%. In stark contrast, January is significantly colder, with temperatures plummeting to a minimum of -22°C (-7°F) and peaking at just 7°C (44°F), yielding an average of -4°C (25°F). Despite receiving less precipitation at 40 mm (1.6 in) over 11 days, the humidity is notably high at 97%. For more detailed information, you can check Saint Petersburg weather in January.
When comparing the weather in September and February, the differences are striking. September experiences milder temperatures ranging from a minimum of 1°C (34°F) to a maximum of 24°C (76°F), while February sees much colder conditions, with temperatures plummeting to a minimum of -28°C (-17°F) and peaking at just 6°C (43°F). Additionally, September has a higher average temperature of 12°C (54°F) compared to February’s average of -4°C (24°F). Precipitation is similar, with both months reporting rain on 14 days, but September records more rainfall at 76 mm (3.0 in) compared to February's 51 mm (2.0 in). Furthermore, the humidity in February is slightly higher at 94% versus September's 90%. For more insights on the unique climate of February, check out Saint Petersburg weather in February.
September and March present contrasting weather conditions in Saint Petersburg. In September, temperatures range from a minimum of 1°C (34°F) to a pleasant average of 12°C (54°F), peaking at 24°C (76°F). With a total precipitation of 76 mm (3.0 in) spread over 14 days, the month is characterized by relatively high humidity at 90%. In sharp contrast, March sees much colder temperatures, with a minimum of -23°C (-9°F), an average of -2°C (29°F), and a maximum of 11°C (53°F). Precipitation is lower at 52 mm (2.0 in) over 12 days, while humidity remains slightly higher at 91%. For more detailed insights on March weather, you can visit Saint Petersburg weather in March.
When comparing the weather in September and April, significant differences emerge. September features milder temperatures, with daily averages around 12°C (54°F) and a maximum of 24°C (76°F), whereas April is much cooler, with an average of only 4°C (39°F) and a maximum of 19°C (67°F). Precipitation is relatively more frequent in September, occurring on 14 days and totaling 76 mm (3.0 in), compared to April, which sees 51 mm (2.0 in) across 11 days. Humidity levels are quite high in both months, with September at 90% and April slightly lower at 87%. For more specific details about the weather in April, you can explore Saint Petersburg weather in April.
In comparing the weather patterns of September and May, notable differences emerge in both temperature and precipitation. September experiences a broader temperature range, with minimums reaching 1°C (34°F) and maximums climbing to 24°C (76°F), while May sees slightly cooler temperatures, with a minimum of -2°C (29°F) and a maximum of 27°C (80°F). Furthermore, September tends to be wetter, accumulating 76 mm (3.0 in) of rainfall over approximately 14 days, compared to May’s 48 mm (1.9 in) across just 9 days. Humidity levels are also higher in September at 90%, contrasting with the more moderate 74% seen in May. For more detailed information, you can visit Saint Petersburg weather in May.
In comparing the weather between September and June, it's clear that June tends to be warmer and drier. In June, temperatures range from a minimum of 4°C (39°F) to a maximum of 33°C (92°F), with an average of 16°C (62°F). In contrast, September sees cooler temperatures, with a minimum of 1°C (34°F) and a maximum of 24°C (76°F), averaging around 12°C (54°F). Additionally, June experiences less precipitation, with only 48 mm (1.9 in) over about 9 days, compared to September's 76 mm (3.0 in) across 14 days. Humidity levels are also lower in June at 77%, compared to a humid 90% in September. For more details, check out Saint Petersburg weather in June.
In comparing the weather of September and July, it's evident that July is generally warmer, with average temperatures ranging from a minimum of 8°C (48°F) to a maximum of 32°C (90°F), while September presents cooler conditions with a range between 1°C (34°F) and 24°C (76°F). Humidity levels are slightly higher in September at 90%, compared to July's 83%, contributing to the damp sensation during the early fall month. Additionally, both months experience significant precipitation, with September receiving 76 mm (3.0 in) over 14 days and July slightly higher at 82 mm (3.2 in) over 13 days. For a more comprehensive look at July weather, you can check Saint Petersburg weather in July.
In comparing the weather between September and August, we observe notable differences in temperatures and precipitation. September experiences cooler temperatures, with minimums dropping to 1°C (34°F) and an average of 12°C (54°F), compared to August's milder minimum of 8°C (47°F) and average of 17°C (62°F). August also boasts higher maximum temperatures, reaching up to 30°C (86°F), while September peaks at a more moderate 24°C (76°F). Precipitation is slightly lower in September at 76 mm (3.0 in) over 14 days, compared to August's 115 mm (4.5 in) over 15 days, although September's humidity rises to 90%, slightly above August's 86%. For more detailed insights about the weather in August, you can visit Saint Petersburg weather in August.
September and October in Saint Petersburg show a distinct transition in weather patterns. September generally has milder temperatures with a minimum of 1°C (34°F) and an average of 12°C (54°F), peaking at a pleasant 24°C (76°F). In contrast, October experiences cooler conditions, featuring a lower minimum temperature of -4°C (25°F) and an average of just 7°C (44°F), with highs reaching only 17°C (63°F). Precipitation also increases slightly from September to October, with 76 mm (3.0 in) over 14 days in September compared to 86 mm (3.4 in) over 16 days in October. Additionally, humidity levels rise from 90% in September to 93% in October, adding to the chill in the air. For more details, check out Saint Petersburg weather in October.
September in Saint Petersburg welcomes milder temperatures, with lows around 1°C (34°F) and highs reaching up to 24°C (76°F). This month receives a notable amount of rainfall, averaging 76 mm (3.0 in) over 14 days, coupled with a relatively high humidity level of 90%. In contrast, November heralds the approach of winter, with temperatures dropping significantly; the minimum plummets to -8°C (18°F) and the maximum peaks at just 10°C (51°F). Precipitation decreases slightly to 55 mm (2.2 in) over 13 days, and humidity remains high at 92%. For a detailed look at what to expect, check out Saint Petersburg weather in November.
In September, weather conditions in Saint Petersburg are relatively mild, with temperatures ranging from a chilly minimum of 1°C (34°F) to a comfortable maximum of 24°C (76°F) and an average of 12°C (54°F). The month experiences significant precipitation, with 76 mm (3.0 in) spread over 14 days, and humidity levels are high at 90%.
In contrast, December brings a stark drop in temperatures, with a minimum of -21°C (-6°F) and a maximum of only 6°C (42°F), resulting in an average temperature of -2°C (28°F). Though precipitation decreases slightly to 69 mm (2.7 in) across 17 days, the humidity remains elevated at 94%, contributing to the cold and crisp winter atmosphere. For more detailed insights, visit Saint Petersburg weather in December.
As summer gives way to autumn, September in Saint Petersburg offers a captivating transition marked by cooler temperatures and increased rainfall. While days are still occasionally warm, the average chill sets in, contrasting sharply with the balmy months prior. With a higher frequency of rainy days, the lush scenery around the city comes alive, enveloped in rich, earthy tones. Despite the humidity hovering around 90%, the vibrant atmosphere invites exploration, making it a unique time for visitors to experience the city's enchanting beauty. For those seeking a deeper understanding of the changing weather patterns, more information can be found at Saint Petersburg Climate.