St. Petersburg in September

In September, St. Petersburg averages 15°C (60°F) during the day and 9°C (48°F) at night, with frequent rain — about 20 days of the month see precipitation (59 mm total).

Shoulder

Conditions are cool — bring a jacket for evenings. Expect daily rain or showers, often in heavy bursts.

September is one of the wetter and less comfortable months in St. Petersburg. If your dates are flexible, consider a different time of year.

15°C
Avg high
9°C
Avg low
20
Rain days
59 mm
Rainfall

How September compares to the rest of the year in St. Petersburg

5th
warmest month of the 12
5th
wettest month of the 12
8%
of yearly rainfall falls in September
12 h 57 min
daylight on the 15th

September is in the middle of the year for warmth in St. Petersburg (5th of 12) and moderately rainy compared to the rest of the year (5th of 12). Daytime temperature runs 6°C above the annual average (9°C). September runs 5°C cooler than August (21°C) and cools 7°C in October (8°C).

September sunrise & sunset in St. Petersburg

🌅
Sunrise (15th)
6:25 AM
🌇
Sunset (15th)
7:22 PM
Day length
12 h 57 min

Times shown for St. Petersburg local time (Europe/Moscow), calculated for the 15th of September. They shift by a few minutes day to day across the month.

Photography light in St. Petersburg — September

Golden-hour and blue-hour windows for the 15th of September, in St. Petersburg's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).

🌅 Blue hour (AM)
5:25 AM – 6:05 AM
🌄 Golden hour (AM)
6:05 AM – 7:05 AM
🌇 Golden hour (PM)
6:42 PM – 7:42 PM
🌆 Blue hour (PM)
7:42 PM – 8:22 PM
Milky Way galactic core
Poor
Core barely rises (or hasn't yet returned for the season). Consider a different month.
Aurora visibility
Fair
Aurora is possible from St. Petersburg but requires a strong geomagnetic event (Kp 5+) plus clear skies — chase nights, don't count on them.

📅 When to book — St. Petersburg in September

Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on September's tier (Shoulder) and St. Petersburg's popularity.

✈ Flights — lead time
6-10 weeks
Sweet spot for value. Major fare-sales (US: Black Friday, EU: post-Easter) hit hardest in shoulder months for shoulder travel.
🏨 Lodging — lead time
4-8 weeks
Lots of selection. Look for shoulder-season packages — many hotels add value (free breakfast, spa credit) to fill rooms.

Crowds & pricing — September in St. Petersburg

Shoulder

St. Petersburg is in a shoulder season month — fewer crowds, slightly lower prices, and a calmer atmosphere than peak weeks. Most major sights stay open with normal hours, though a handful of seasonal restaurants or boat trips may run reduced schedules. Many regulars consider these months the best time to visit because you trade a small amount of weather reliability for a much more pleasant on-the-ground experience.

Sun & mosquito risk — September in St. Petersburg

☀️ UV Index (noon, 15th)
5.7
Moderate
Use SPF 15-30 for prolonged outdoor exposure; sunglasses recommended at peak hours.
🦟 Mosquito risk
●●●○○
Moderate
Active mosquito season. DEET 25-30% repellent recommended, especially at dawn/dusk.

UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.

St. Petersburg in other months

MonthAvg highAvg lowRainfallRain daysSnow days
January -3°C / 26°F -7°C / 19°F 46 mm 21
February -1°C / 29°F -6°C / 21°F 43 mm 18
March 3°C / 37°F -4°C / 24°F 40 mm 18
April 9°C / 48°F 0°C / 32°F 49 mm 16
May 16°C / 60°F 6°C / 44°F 57 mm 17
June 20°C / 69°F 12°C / 54°F 60 mm 19
July 22°C / 71°F 14°C / 58°F 89 mm 22
August 21°C / 69°F 13°C / 56°F 96 mm 21
September 15°C / 60°F 9°C / 48°F 59 mm 20
October 8°C / 46°F 3°C / 38°F 66 mm 21
November 2°C / 36°F -1°C / 30°F 53 mm 20
December -1°C / 31°F -4°C / 24°F 51 mm 20

Other cities with similar September weather

🌍 See the full ranked list of climate twins for St. Petersburg in September →

Frequently asked questions

How hot is St. Petersburg in September?

In September, St. Petersburg averages a high of 15°C (60°F) and a low of 9°C (48°F) — generally cool.

Does it rain a lot in St. Petersburg in September?

September is quite rainy in St. Petersburg, with about 20 rainy days on average.

Is September a good time to visit St. Petersburg?

September is cool but on the rainy side. It suits travelers who are comfortable with cool weather; check the month-by-month ranking to compare it against the rest of the year.

What should I pack for St. Petersburg in September?

Pack a warm jacket and layers, plus a compact umbrella or rain jacket. See the full September packing list for St. Petersburg for a complete, climate-based checklist.

Open St. Petersburg on the interactive map

Check the live 10-day forecast and sunrise/sunset.