September
Weather in September
September begins to signify the end of summer, ushering Alderney into the first hints of autumn. A marked drop is exhibited in daylight hours, coming down to an average of 12.6 per day. There's a minimal shift in sea temperature hovering at 17.4°C (63.3°F), exhibiting the highest sea temperature. September serves as a wonderful transitional month, retaining the warmth of the departing summer and introducing the crispness of the incoming autumn.
Note: The majority find it unenjoyable to swim in 17.4°C (63.3°F). Breathing becomes tougher as the water temperature descends under 21°C (69.8°F).
On the first day of the month, sunrise is at 06:25 and sunset at 19:52. On the last day of September, sunrise is at 07:08 and sunset at 18:49 BST.
Sea temperature
September is the month with the warmest seawater, with an average sea temperature of 17.4°C (63.3°F).Note: The majority find it unenjoyable to swim in 17.4°C (63.3°F). Breathing becomes tougher as the water temperature descends under 21°C (69.8°F).
Daylight
The average length of the day in September is 12h and 36min.On the first day of the month, sunrise is at 06:25 and sunset at 19:52. On the last day of September, sunrise is at 07:08 and sunset at 18:49 BST.
Updated: Jun 5, 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
When is the sea warmest?
With an average sea temperature of 17.4°C (63.3°F), September is the month with the warmest seawater.
What is the sea water temperature in September?
In Alderney, the average seawater temperature in September is 17.4°C (63.3°F). Swimming in 17.4°C (63.3°F) is not enjoyable for the majority. Controlling breathing becomes progressively more difficult as surface water temperature decreases below 21°C (69.8°F).
How many hours of daylight does Alderney have in September?
In Alderney, the average day length in September is 12h and 36min.
When are sunrise and sunset in September?
On the first day of September, sunrise is at 06:25 and sunset at 19:52. On the last day of the month, sunrise is at 07:08 and sunset at 18:49 BST.
Average sea temperature in September
Alderney, Guernsey
- Average sea temperature in September: 17.4°C
The best month for swimming (with the highest average sea temperature) is September (17.4°C).
The coldest month (with the lowest average sea temperature) is March (9.3°C).
Average daylight in September
Alderney, Guernsey
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 16h and 12min).
The month with the shortest days is December (Average daylight: 8h and 12min).
