Saint Petersburg weather in September
September in Saint Petersburg: cool, a little rain, with clean air — a great time to visit.
#5 of 12 months in Saint Petersburg · #366 of 604 destinations to visit in September · comfort 76/100 (tier B)
Updated June 2026 · climate normals from ERA5 reanalysis
Saint Petersburg climate normals — September
| Daytime high | 15°C / 58°F | 🙂 cool |
|---|---|---|
| Nighttime low | 9°C / 49°F | |
| Feels like (high) | 12°C / 54°F | |
| Rainfall | 61 mm / 2.4 in | 🌦 some rain |
| Rainy days | 12 days | |
| Humidity | 82% | 💦 very humid |
| Dew point | 9°C / 49°F | |
| Sunshine | 7.7 h/day | |
| Daylight | 12.9 h | |
| Wind | 20 km/h / 13 mph | |
| Air quality (US AQI) | 38 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
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Saint Petersburg in September — FAQ
- Is September a good time to visit Saint Petersburg?
- September in Saint Petersburg: cool, a little rain, with clean air — a great time to visit. It ranks #5 of 12 months for Saint Petersburg on SeasonMap's comfort score (76/100).
- What is the weather like in Saint Petersburg in September?
- In September, Saint Petersburg averages a daily high of 14.6°C and a low of 9.4°C, with about 61.1 mm of rain over roughly 12 rainy days.
- What is the air quality in Saint Petersburg in September?
- Saint Petersburg has a mean US Air Quality Index of about 38 in September.