The highest day temperature in September 2025 was 77°F. The lowest night temperature was 33°F. The average values for day and night temperatures during September were 64.2°F и 51.7°F respectivly.

The average sea surface temperature in September 2025 for Shlisselburg was 58.6°F. The maximum and minimum values were 49.2°F and 65.0°F respectively.

Most of the days in September are gloomy but you can also expect sunny days.

Precipitation total in September for Shlisselburg is 0.6 in. It makes september one of the least rainy months of the year.

The average wind speed in September is 7.7 mph. This value is relatively stable throughout the year.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Shlisselburg in September is 6.4 hours.