Last updated: February 24, 2025
In September, St. Petersburg, United States experiences warm and humid weather, with daily temperatures fluctuating between a maximum of 32°C (89°F) and a minimum of 23°C (74°F), yielding an average of 27°C (82°F). The month is characterized by frequent rain, accumulating an average of 143 mm (5.6 in) over 18 days, contributing to the city's overall 78% humidity. Visitors can expect a blend of sunny spells and occasional downpours, making it essential to stay prepared for the shifting conditions.
As summer transitions to autumn in St. Petersburg, September remains warm and inviting, showcasing mild temperatures that attract visitors and locals alike. With minimums around 23°C (74°F) and average highs reaching 32°C (89°F), the month retains a hint of summer warmth while gently signaling the cooler days ahead. This gradual decline from the peak summer heat—where July and August boast the same max temperatures—indicates a subtle shift in the season. Overall, September offers a delightful balance, making it an ideal time for outdoor activities, with sunny days interspersed with the first whispers of fall, perfect for embracing the vibrant coastal city.
September marks a notable transition in St. Petersburg's precipitation pattern, reflecting the tail end of the summer rainy season. With 143 mm (5.6 in) of rainfall over 18 days, it's a month that balances lingering summer showers with the onset of drier autumn weather. This contrasts sharply with the hefty downpours of July and August, where the city sees 204 mm (8.0 in) and 219 mm (8.6 in), respectively. As September progresses, rainfall tapers off, paving the way for October's anticipated 67 mm (2.6 in). This trend underscores a peak in precipitation during the summer months, gradually giving way to a more moderate climate, making September a key month for both moisture and transition in St. Petersburg.
In St. Petersburg, United States, September marks a subtle shift in humidity patterns, as levels settle at 78%. This figure represents a slight increase from the drier months of July and August, both recorded at 74%. The trend throughout the year showcases the area's generally high humidity, particularly in the colder months, with January and February hovering at a notable 82%. As the seasons transition, September's humidity reflects the lingering warmth of summer while hinting at the forthcoming autumn chill. It’s a month where the humidity begins to inch up again, setting the stage for the more humid months ahead.
As summer transitions to autumn in St. Petersburg, the UV Index remains notably high throughout September, maintaining an extreme exposure category with a level of 11. This trend mirrors the intense UV radiation experienced in the peak summer months of June and July, where readings also hit 12. Interestingly, although September sees a slight dip from the peak summer levels, the burn time remains a brief 10 minutes, emphasizing the need for protective measures when outdoors. As the season progresses into October, residents can expect a decrease in intensity, with the UV Index falling to 9. For detailed insights on UV exposure and safety, visit St. Petersburg UV Index.
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As summer transitions to autumn, September in St. Petersburg shines with an impressive 311 hours of sunshine. This notable amount reflects a slight dip from the summer peak, with July and August basking in 319 and 316 hours, respectively. However, September retains its warmth and brightness, marking it as a fantastic time for outdoor lovers to enjoy the city before the cooler months set in. The trend reveals a gradual reduction in sunshine as the year progresses, with October following closely behind at 300 hours. Nonetheless, September’s generous sun ensures that residents and visitors can relish in beautiful days, soaking up the last remnants of summer's glow.
In St. Petersburg, the chances of sunny weather experience notable fluctuations throughout the year. After a series of increasing probabilities from January to April, where sunlight is more likely, the summer months take a significant dip, with June, July, and August seeing only 18%, 23%, and 17% of sunny conditions, respectively. September offers a small rebound, presenting a 33% chance of sunshine, which, while better than the dog days of summer, remains below the annual average. As the year progresses into October and November, the likelihood of sun climbs again, peaking at 55% in November. This pattern indicates that while September can still hold some sunny spells, the overall trend reflects a shift toward cooler and cloudier weather as fall approaches.
As summer wanes in St. Petersburg, the daylight duration in September settles at a comfortable 12 hours, mirroring the longer days of March and April. This month serves as a gentle transition, where the lingering warmth of summer begins to give way to the cool embrace of autumn. While the city enjoys a steady daylight pattern throughout the summer months, the gradual decline in daylight hours begins in September, leading to a softer, golden light that enhances the vibrant fall colors. It's a reminder of nature’s rhythm, where the balance of light and darkness ebbs and flows, casting a spell of tranquility before the shorter days of October and November arrive.
As September arrives in St. Petersburg, the breezy charm of summer gives way to a gentle decline in wind speed, averaging a modest 3.4 m/s (8 mph). This month marks a notable shift, as the winds soften compared to the stronger 5.0 m/s (11 mph) experienced in the spring and early summer. Interestingly, September’s calmness follows a trend of diminishing wind, with the lowest speeds recorded since June. With these tranquil breezes, the city seems to welcome the onset of autumn, creating a serene atmosphere perfect for leisurely strolls along the waterfront. As the season transitions, the fluctuations in wind speed also signal an impending change in St. Petersburg’s weather patterns, hinting at the brisker days to come.
The weather in St. Petersburg 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 St. Petersburg and find detailed weather information for every month.
September and January present stark contrasts in weather patterns. In September, temperatures are warm, with an average of 27°C (82°F), peaking at 32°C (89°F), and accompanied by high humidity at 78%. This month sees considerable rainfall, totaling 143 mm (5.6 in) over 18 days, making it a wet and steamy time of year. Conversely, January brings much cooler temperatures, with a minimum of 3°C (37°F) and an average of 17°C (62°F), with highs reaching just 24°C (75°F). Rainfall in January is significantly lower, at 40 mm (1.6 in) across only 4 days, while humidity remains high at 82%. For more information on January weather specifics, visit St. Petersburg weather in January.
September and February showcase contrasting weather patterns in St. Petersburg, Florida. In September, temperatures are notably warmer, with a minimum of 23°C (74°F) and an average of 27°C (82°F), peaking at a maximum of 32°C (89°F). This month experiences significant rainfall, totaling 143 mm (5.6 in) over 18 days, and maintaining a humidity level of 78%. Conversely, February brings a much cooler climate, where temperatures range from a low of 9°C (48°F) to an average of 19°C (66°F), with highs reaching 25°C (78°F). This month is drier, with only 50 mm (2.0 in) of precipitation over just 5 days, and the humidity remains relatively high at 82%. For more details on February weather in St. Petersburg, check St. Petersburg weather in February.
In September, St. Petersburg experiences significantly warmer weather, with average temperatures ranging from a minimum of 23°C (74°F) to a maximum of 32°C (89°F), while March sees cooler temperatures, peaking at around 26°C (80°F). Additionally, September is marked by much higher precipitation, accumulating 143 mm (5.6 in) over 18 rainy days, compared to March’s lighter rainfall of just 20 mm (0.8 in) across only 3 days. Humidity levels remain fairly consistent, at 78% in September and slightly higher at 79% in March. For a closer look at March's weather specifics, you can check St. Petersburg weather in March.
September and April present striking differences in weather conditions. In September, temperatures range from a minimum of 23°C (74°F) to a maximum of 32°C (89°F), making it notably warmer than April, where temperatures vary from 12°C (54°F) to 28°C (83°F). Additionally, September experiences significantly higher precipitation, with 143 mm (5.6 in) over 18 days, compared to April's 60 mm (2.4 in) spread over just 7 days. Despite both months having a humidity level of 78%, the overall climate in September feels much more tropical, while April tends to be mild and more pleasant. For a detailed look at April weather, you can visit St. Petersburg weather in April.
In comparing the weather of September and May, September typically experiences warmer temperatures, with average highs reaching around 32°C (89°F) compared to May's maximum of 30°C (87°F). Additionally, September tends to be wetter, with an average precipitation of 143 mm (5.6 in) over 18 days, while May averages 105 mm (4.1 in) across only 10 days. Humidity levels are quite similar, hovering around 78% in September and 76% in May, creating a muggy atmosphere in both months. For more detailed insights, you can check St. Petersburg weather in May.
In comparing the weather of September and June, both months showcase similar average temperatures, with minimums around 23°C (74°F) and maximums reaching up to 32°C (89°F). However, September typically experiences slightly less precipitation, averaging 143 mm (5.6 in) over 18 rainy days, compared to June's 174 mm (6.8 in) across 19 rainy days. While humidity levels are fairly close, September tends to be a bit more humid at 78%, compared to June's 75%. For a more detailed look at June's weather conditions, you can check the following link: St. Petersburg weather in June.
When comparing the weather in September and July, both months showcase warm temperatures, with September having a slight edge in cooler mornings, with a minimum temperature of 23°C (74°F) compared to July's minimum of 25°C (77°F). The average temperature remains similar, around 27°C (82°F) in September and 28°C (82°F) in July, while the maximum temperature peaks at 32°C (89°F) in September and 32°C (90°F) in July. Notably, September experiences less rainfall, with 143 mm (5.6 in) of precipitation over 18 days, contrasted with July's 204 mm (8.0 in) over 25 days, leading to a slightly higher humidity level in September at 78% versus July's 74%. For more details, you can check St. Petersburg weather in July.
September weather shows a slight cooling trend compared to August, with average temperatures dropping from 28°C (83°F) to 27°C (82°F). While the maximum temperatures remain consistent at 32°C (90°F) in both months, September's minimum temperature is a bit lower at 23°C (74°F), compared to August's 25°C (77°F). Additionally, September experiences more precipitation over fewer days, with 143 mm (5.6 in) falling over 18 days compared to August's 219 mm (8.6 in) spread across 25 days. This results in a slightly higher humidity level in September at 78%, compared to August's 74%. For a more detailed comparison, check out St. Petersburg weather in August.
In September, the weather in St. Petersburg is notably warmer, with average temperatures around 27°C (82°F) and highs reaching up to 32°C (89°F). The month is also characterized by significant humidity at 78% and substantial precipitation totaling 143 mm (5.6 in) across 18 days. In contrast, October brings a refreshing change with cooler temperatures, featuring a minimum of 15°C (59°F) and an average of 26°C (79°F), while highs drop slightly to 31°C (87°F). The precipitation also decreases to 67 mm (2.6 in) over just 10 days, and the humidity remains similar at 79%. This shift makes October a more comfortable month overall. For more detailed information on October weather, visit St. Petersburg weather in October.
In September, the weather is significantly warmer, with temperatures ranging from a minimum of 23°C (74°F) to a maximum of 32°C (89°F) and an average of 27°C (82°F). The month also experiences substantial rainfall, with 143 mm (5.6 in) of precipitation over about 18 days, contributing to a humidity level of 78%. In contrast, November sees much cooler temperatures, with a minimum of 12°C (54°F) and a maximum of 28°C (83°F), averaging around 21°C (70°F). Additionally, November has much lower precipitation at 46 mm (1.8 in) over only 6 days and slightly higher humidity at 82%. For more information on the November weather specifics, you can visit St. Petersburg weather in November.
The weather in September is markedly warmer and more humid compared to December. September sees average temperatures around 27°C (82°F), with highs reaching up to 32°C (89°F) and a significant amount of rainfall, totaling 143 mm (5.6 in) over 18 days, contributing to a humidity level of 78%. In contrast, December experiences much cooler temperatures, with an average of 19°C (66°F), and highs only reaching 25°C (77°F). Precipitation during December is less frequent and lighter, totaling 66 mm (2.6 in) over just 6 days, while humidity slightly increases to 84%. For more detailed information on December weather in St. Petersburg, visit St. Petersburg weather in December.
As September arrives in St. Petersburg, the weather transitions into a more refreshing phase, departing from the intense summer heat. With temperatures averaging around 27°C (82°F), this month provides a comfortable respite, especially compared to the scorching highs of July and August. However, the air carries a touch of humidity at 78%, contributing to the occasional rain, as 18 days see varying amounts of precipitation totaling 143 mm (5.6 in). This mix of warmth and rain creates dynamic conditions, making September a unique time to experience the city's charm. To dive deeper into what to expect throughout the year, visit St. Petersburg Climate.