Sea Temperature in Roscoff in September

© Thomas Jaouen

Complete information on the sea temperature range in the Celtic Sea in Roscoff in September. Historical daily data. Climate details for September. Tips on swimming conditions and beach relaxation in Roscoff. We find every spot where you can swim and tell you what the water temperature is there today and throughout the year.

Roscoff Climate and Swimming Opportunities in September

Roscoff lies within the Brittany in France. The average daytime temperature in Roscoff in September is 20°C (67°F), while the nighttime average is 13°C (55°F). There are typically 10 rainy days during the month, with a total precipitation of 63 mm (2.5 inches). The daylight duration in September in Roscoff is 12 hours, with an average of 6 hours of sunshine per day. The average wind speed in September is 18 km/h (11 mph), and the humidity level is around 83%.

The water temperature in Roscoff in September ranges from 15°C to 16°C (59°F to 61°F). At the beginning of the month, the average temperature is around 17°C (63°F), shifting to 16°C (61°F) by mid-September and reaching 16°C (61°F) in the last ten days. Overall, the average sea temperature in Roscoff for September is 16°C (61°F). Ideal conditions for a refreshing swim, though some may still find it a bit cool.

Frequently Asked Questions About Water Temperatures in September in Roscoff