September is one of the warmer months of the year in Saint Petersburg, with average highs near 29.6°C and lows around 23.9°C (mean 26.8°C). It is a relatively wet time of year, averaging 178 mm of rainfall and 83% relative humidity across the period.
September is one of the warmer months of the year in Saint Petersburg. Across 45 years of records, the warmest September in Saint Petersburg was 2024 — when the month averaged 28.2°C — while the coldest was 2001 at 25.3°C. Typical September days reach 29.6°C with nights near 23.9°C. The long-term trend is warming, about 0.3°C per decade.
September is a relatively wet time of year in Saint Petersburg, averaging 178 mm of rainfall. The wettest September on record was 2004 with 407 mm, while the driest was 2019 at 49 mm.
Relative humidity in Saint Petersburg during September averages 83%. The most humid September was 2004 at 88%, and the least humid was 1996 at 74%.
September receives about 5.2 kWh/m²/day of solar energy in Saint Petersburg. The sunniest September was 2019 at 5.9 kWh/m²/day, and the cloudiest was 1998 at 4.5.
Average wind speed in Saint Petersburg during September is 2.6 m/s. The windiest September was 2004 at 4.5 m/s, while the calmest were 1987 and 2021 at 1.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 26.2°C | 26.7°C | 26.6°C | 27.0°C | 27.4°C | +1.2°C |
| Avg High | 29.0°C | 29.6°C | 29.4°C | 29.8°C | 30.4°C | +1.4°C |
| Avg Low | 23.3°C | 23.9°C | 23.9°C | 24.1°C | 24.4°C | +1.1°C |
| Avg Rain | 182 mm | 153 mm | 200 mm | 177 mm | 177 mm | -4 mm |
September temperatures in Saint Petersburg have risen by about 1.8°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 16°C (1981) to a record high of 33.2°C (2020).
Rainfall in September is a relatively wet time of year, averaging 178 mm, with a wettest year of 407 mm.
A quieter season to visit Saint Petersburg
If your dates are flexible, the more temperate months of April and November tend to be the most comfortable for visiting Saint Petersburg. That said, September — with days averaging 29.6°C and nights around 23.9°C (mean 26.8°C) and higher rainfall (178 mm) — can still be rewarding for travellers who don't mind the warmth, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 30.7°C | 27.4°C | 24.0°C | 32.4°C | 21.5°C | 62 mm | 79% | 2.4 m/s | 5 |
| 2024 🔥 | 30.9°C | 28.2°C | 25.4°C | 32.1°C | 23.5°C | 198 mm | 83% | 2.4 m/s | 5.2 |
| 2023 | 31.5°C | 28.0°C | 24.5°C | 33.2°C | 21.3°C | 120 mm | 76% | 2.1 m/s | 5.5 |
| 2022 | 29.7°C | 26.9°C | 24.1°C | 32.8°C | 18.0°C | 288 mm | 84% | 2.5 m/s | 4.7 |
| 2021 | 29.5°C | 26.9°C | 24.3°C | 30.9°C | 20.9°C | 207 mm | 82% | 1.9 m/s | 5 |
| 2020 | 29.9°C | 27.1°C | 24.3°C | 33.2°C | 17.8°C | 186 mm | 84% | 2.9 m/s | 5 |
| 2019 | 30.6°C | 27.3°C | 23.9°C | 32.6°C | 20.3°C | 49 mm | 80% | 3.1 m/s | 5.9 |
| 2018 | 30.4°C | 27.7°C | 24.9°C | 32.1°C | 23.5°C | 142 mm | 83% | 2.2 m/s | 5.7 |
| 2017 | 29.6°C | 26.9°C | 24.1°C | 31.3°C | 22.4°C | 260 mm | 83% | 2.6 m/s | 5.3 |
| 2016 | 29.9°C | 27.2°C | 24.5°C | 31.3°C | 21.9°C | 176 mm | 84% | 2.3 m/s | 5.4 |
| 2015 | 29.2°C | 26.8°C | 24.3°C | 31.1°C | 20.9°C | 155 mm | 85% | 2.2 m/s | 4.8 |
| 2014 | 29.5°C | 26.7°C | 23.9°C | 32.9°C | 21.8°C | 326 mm | 83% | 2 m/s | 4.7 |
| 2013 | 29.7°C | 26.7°C | 23.8°C | 31.3°C | 20.8°C | 214 mm | 83% | 2.5 m/s | 5.3 |
| 2012 | 29.1°C | 26.2°C | 23.3°C | 31.1°C | 19.2°C | 132 mm | 83% | 2.4 m/s | 5.1 |
| 2011 | 29.7°C | 26.9°C | 24.0°C | 31.3°C | 22.2°C | 203 mm | 81% | 2 m/s | 5.1 |
| 2010 | 30.4°C | 27.1°C | 23.9°C | 32.4°C | 21.2°C | 113 mm | 80% | 2.6 m/s | 5.7 |
| 2009 | 29.5°C | 26.8°C | 24.1°C | 31.0°C | 19.0°C | 168 mm | 84% | 2.2 m/s | 5.2 |
| 2008 | 29.6°C | 26.6°C | 23.6°C | 31.3°C | 18.9°C | 65 mm | 82% | 3.1 m/s | 5.3 |
| 2007 | 29.9°C | 27.1°C | 24.2°C | 31.3°C | 21.8°C | 141 mm | 82% | 2.7 m/s | 5.4 |
| 2006 | 29.4°C | 26.5°C | 23.7°C | 31.0°C | 21.0°C | 191 mm | 81% | 2 m/s | 5.4 |
| 2005 | 30.7°C | 27.4°C | 24.1°C | 33.0°C | 22.1°C | 71 mm | 79% | 3 m/s | 5.3 |
| 2004 🌧️ | 28.9°C | 26.6°C | 24.3°C | 30.9°C | 21.2°C | 407 mm | 88% | 4.5 m/s | 4.8 |
| 2003 | 28.7°C | 26.1°C | 23.5°C | 30.4°C | 20.0°C | 165 mm | 86% | 2.7 m/s | 4.9 |
| 2002 | 29.7°C | 27.1°C | 24.5°C | 30.9°C | 23.3°C | 187 mm | 87% | 2.8 m/s | 4.9 |
| 2001 ❄️ | 27.7°C | 25.3°C | 22.9°C | 30.1°C | 17.3°C | 338 mm | 86% | 2.5 m/s | 4.7 |
| 2000 | 29.4°C | 26.7°C | 24.0°C | 31.3°C | 20.5°C | 264 mm | 84% | 2.9 m/s | 5.1 |
| 1999 | 29.3°C | 26.5°C | 23.7°C | 32.2°C | 18.5°C | 123 mm | 82% | 3 m/s | 4.8 |
| 1998 | 29.1°C | 26.8°C | 24.6°C | 31.6°C | 21.3°C | 330 mm | 87% | 3.3 m/s | 4.5 |
| 1997 | 30.3°C | 27.0°C | 23.7°C | 32.8°C | 20.8°C | 205 mm | 77% | 2.4 m/s | 5.4 |
| 1996 | 31.1°C | 27.5°C | 24.0°C | 32.9°C | 19.9°C | 93 mm | 74% | 2.6 m/s | 5.5 |
| 1995 | 29.8°C | 26.9°C | 24.0°C | 30.9°C | 22.0°C | 110 mm | 83% | 2.2 m/s | 5.2 |
| 1994 | 28.2°C | 25.8°C | 23.5°C | 31.2°C | 20.5°C | 225 mm | 87% | 2.5 m/s | 4.7 |
| 1993 | 29.4°C | 26.7°C | 24.0°C | 31.1°C | 18.7°C | 123 mm | 82% | 2.2 m/s | 5.3 |
| 1992 | 28.8°C | 26.4°C | 23.9°C | 30.8°C | 20.6°C | 144 mm | 85% | 2.5 m/s | 5.2 |
| 1991 | 29.5°C | 26.5°C | 23.5°C | 31.1°C | 18.0°C | 86 mm | 83% | 2.8 m/s | 5.6 |
| 1990 | 30.3°C | 27.1°C | 23.8°C | 32.3°C | 18.5°C | 90 mm | 77% | 2.4 m/s | 5.3 |
| 1989 | 29.8°C | 26.9°C | 23.9°C | 31.4°C | 21.7°C | 181 mm | 83% | 2.4 m/s | 5.3 |
| 1988 | 29.3°C | 26.7°C | 24.1°C | 30.8°C | 20.6°C | 322 mm | 86% | 2.9 m/s | 5.1 |
| 1987 | 30.0°C | 27.1°C | 24.2°C | 32.3°C | 21.8°C | 127 mm | 78% | 1.9 m/s | 4.7 |
| 1986 | 29.6°C | 26.6°C | 23.6°C | 30.7°C | 21.8°C | 111 mm | 82% | 2.2 m/s | 5.5 |
| 1985 | 28.4°C | 25.6°C | 22.8°C | 30.1°C | 20.0°C | 126 mm | 85% | 3.1 m/s | 5.5 |
| 1984 | 28.9°C | 25.8°C | 22.7°C | 31.2°C | 21.2°C | 141 mm | 80% | 3.4 m/s | 5.3 |
| 1983 | 28.0°C | 25.5°C | 23.0°C | 30.3°C | 17.8°C | 220 mm | 85% | 2.8 m/s | — |
| 1982 | 28.6°C | 25.9°C | 23.2°C | 31.3°C | 18.8°C | 277 mm | 84% | 2.4 m/s | — |
| 1981 | 28.7°C | 25.7°C | 22.6°C | 30.8°C | 16.0°C | 128 mm | 82% | 2.4 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 29.6°C with lows near 23.9°C (mean 26.8°C), based on 45 years of NASA POWER data.
September averages 178 mm of rainfall in Saint Petersburg, a relatively wet time of year. The wettest on record was 407 mm in 2004.
The hottest September reached 33.2°C in 2020. The coldest dipped to 16°C in 1981.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.8°C. Daytime highs moved from 28.5°C to 30.5°C and overnight lows from 22.9°C to 24.5°C over the same span.
September is one of the warmer months of the year in Saint Petersburg and a relatively wet time of year, so plan for around 29.6°C daytime highs and 23.9°C at night.
Not quite — September is the 9th coolest month in Saint Petersburg, averaging 26.8°C.
For September in Saint Petersburg, pack light layers you can adjust through the day, with typical highs of 29.6°C and lows of 23.9°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 83% — quite humid.
Average wind speed in September is 2.6 m/s. The windiest September on record averaged 4.5 m/s (2004).
The wettest September on record was 2004 with 407 mm. On average, September sees 178 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Saint Petersburg behaves each September, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for September specifically, along with year-by-year records and how the month has changed over the decades.
