September weather forecastNynäshamn, Sweden
September
Weather in September
Sea temperature
In Nynäshamn, Sweden, in September, the average water temperature is 14.8°C (58.6°F).Note: While a brief time in 14.8°C (58.6°F) at 13°C (55.4°F) is already bracing, plunging below 10°C (50°F) can severely affect breathing and introduce a cold shock, relying on your physical state.
Daylight
In September, the average length of the day is 12h and 50min.On the first day of September in Nynäshamn, sunrise is at 05:47 and sunset at 19:48. On the last day of the month, sunrise is at 06:51 and sunset at 18:24 CEST.
Updated: Feb 2, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
In September, the average sea temperature in Nynäshamn is 14.8°C (58.6°F). At temperatures below 10°C (50°F), swimming in a suitably protected swimsuit is feasible; otherwise, cold shock and loss of breathing control are imminent. Even a short swim, without thermal protection, at temperatures around 13°C (55.4°F) is not comfortable.
The average day length in September is 12h and 50min.
In September, on the first day of the month, sunrise is at 05:47 and sunset at 19:48. On the last day of the month, in Nynäshamn, sunrise is at 06:51 and sunset at 18:24 CEST.
Average sea temperature in September
Nynäshamn, Sweden
- Average sea temperature in September: 14.8°C
The best month for swimming (with the highest average sea temperature) is August (18.7°C).
The coldest month (with the lowest average sea temperature) is February (1°C).
Average daylight in September
Nynäshamn, Sweden
- Average daylight in September: 12h and 48min
The month with the longest days is June (Average daylight: 18h and 18min).
The month with the shortest days is December (Average daylight: 6h and 24min).





