Climate and monthly weather forecast
Weather in January
In January, the average sea temperature in Sennen, United Kingdom, is 10.4°C (50.7°F). Note: Being in 10.4°C (50.7°F) waters at 13°C (55.4°F) is discomforting, but anything below 10°C (50°F) can jeopardize breathing and induce cold shock, factoring in physical endurance. Weather in January »
Weather in February
In February, the average sea temperature in Sennen, United Kingdom, is 10°C (50°F). Note: To swim in 10°C (50°F) at less than 10°C (50°F), ensure you're well-protected. Weather in February »
Weather in March
The month with the coldest seawater in Sennen, United Kingdom, is March, with an average sea temperature of 9.7°C (49.5°F). Note: Caution: 9.7°C (49.5°F) temperatures below 10°C (50°F) during swimming can result in intense cold shock and quickened breathing. Weather in March »
Weather in April
In Sennen, United Kingdom, the average seawater temperature in April is 10.7°C (51.3°F). Note: To swim in 10.7°C (51.3°F) at less than 10°C (50°F), ensure you're well-protected. Weather in April »
Weather in May
In Sennen, United Kingdom, in May, the average water temperature is 12°C (53.6°F). Note: You can swim in 12°C (53.6°F) below 10°C (50°F) with proper thermal wear; failing that, the cold shock and respiratory challenges are nearly certain. Weather in May »
Weather in June
In Sennen, United Kingdom, the average seawater temperature in June is 14.2°C (57.6°F). Note: With the appropriate swimsuit, one can swim in 14.2°C (57.6°F) even if temperatures dip below 10°C (50°F); otherwise, be ready for cold shock and breath issues. Weather in June »
Weather in July
In Sennen, United Kingdom, the average seawater temperature in July is 16.6°C (61.9°F). Note: Swimming in 16.6°C (61.9°F) is not enjoyable for the majority. Weather in July »
Weather in August
The month with the warmest seawater in Sennen, United Kingdom, is August, with an average sea temperature of 17.1°C (62.8°F). Note: Swimming is not enjoyable for most people in water that is 17.1°C (62.8°F). Weather in August »
Weather in September
In Sennen, United Kingdom, in September, the average water temperature is 16.5°C (61.7°F). Note: Swimming is not an enjoyable activity for the majority when the water is at 16.5°C (61.7°F). Weather in September »
Weather in October
In Sennen, United Kingdom, in October, the average water temperature is 14.8°C (58.6°F). Note: Swimming in 14.8°C (58.6°F) can be lethal. Merely spending a few minutes in 13°C (55.4°F) waters feels harsh, and venturing below 10°C (50°F) might disrupt breathing control and bring about cold shock, contingent on individual resilience. Weather in October »
Weather in November
In Sennen, United Kingdom, the average seawater temperature in November is 13.3°C (55.9°F). Note: One needs to be cautious in 13.3°C (55.9°F) waters. Weather in November »
Weather in December
In Sennen, United Kingdom, in December, the average water temperature is 11.8°C (53.2°F). Note: Swimming in 11.8°C (53.2°F) is deemed hazardous. Exposure to temperatures below 10°C (50°F) leads to immediate severe cold shock and hyperventilation. Weather in December »
Updated: Feb 6, 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
What is the month with the coldest sea water in Sennen?
The month with the coldest seawater is March, with an average sea temperature of 9.7°C (49.5°F).
When are the longest days in Sennen?
With an average of 16h and 18min of daylight, June has the longest days of the year in Sennen.
When is the sea warmest in Sennen?
The month with the warmest seawater is August, with an average sea temperature of 17.1°C (62.8°F).
When is Daylight Saving Time (DST) in Sennen?
On Sunday, 27. October 2024, at 2:00 am, Daylight Saving Time ends in Sennen, United Kingdom, and the time zone changes from BST to GMT. The next Daylight Saving Time starts on Sunday, 30. March 2025, at 1:00 am, and the time zone reverts from GMT to BST.
What is the month with the shortest days in Sennen?
December has the shortest days of the year in Sennen, with an average of 8h and 12min of daylight.
Average sea temperature
Sennen, United Kingdom
The best month for swimming (with the highest average sea temperature) is August (17.1°C).
The coldest month (with the lowest average sea temperature) is March (9.7°C).
Average daylight
Sennen, United Kingdom
- Average daylight in January:
8h and 4min - Average daylight in February:
10h and 1min - Average daylight in March:
11h and 5min - Average daylight in April:
13h and 5min - Average daylight in May:
15h and 2min - Average daylight in June:
16h and 2min
- Average daylight in July:
15h and 5min - Average daylight in August:
14h and 2min - Average daylight in September:
12h and 4min - Average daylight in October:
10h and 4min - Average daylight in November:
9h and 1min - Average daylight in December:
8h and 1min
The month with the longest days is June (Average daylight: 16h and 18min).
The month with the shortest days is December (Average daylight: 8h and 12min).
