Sun, sea & sand

Roscoff weather in September

Temperature, sea and sunshine in September: long-term averages from 30 years of weather data, not a forecast.

21

Holiday weather in September

Poor

Best time to visit: April – September

What is the weather like in Roscoff in September?

In September, Roscoff is mild: daytime highs average 18 °C, and nights cool down to about 14 °C. The sea averages 15.9 °C – swimming is only for the hardy. Expect around 6 hours of sunshine a day. Rain is frequent, with about 10 rainy days and 53 mm in total. All in all, September is not an ideal month for a holiday in Roscoff.

September compared

How the weather changes from August to October. Tap a month to open it.

AugustAugSeptemberSepOctoberOct
Score21218
Day19°18°16°
Night15°14°12°
Sea16°16°15°
Sun6 h6 h4 h
Rain days111014

More details for September

Daylight
12 h 41 min07:51 – 20:32
UV index
4 · moderateclear sky, noon (estimate)All months
Muggy days
0 daysdew point 18 °C or moreAll months
Wind
21 km/haverage daily peakAll months
Cloud cover
61 %on averageAll months
Hot days
0 days30 °C or more
Time zone
UTC+2Europe/Paris

How the score comes together

  • Temperatureweight 35 %0 %
  • Seaweight 25 %0 %
  • Sunshineweight 20 %45 %
  • Few rainy daysweight 20 %58 %

Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.

What to pack in September

  • Sunscreen
  • A jumper for the evenings
  • Rain jacket or umbrella

Roscoff in September: quick answers

Is Roscoff hot in September?

No. In September, Roscoff is mild: daytime highs average 18 °C and nights drop to about 14 °C.

Can you swim in Roscoff in September?

Only if you don't mind cold water: in September the sea averages just 15.9 °C. Comfortable swimming temperatures are not reached at any time of year.

Does it rain much in Roscoff in September?

Rain is frequent, with about 10 rainy days and 53 mm in total.

Roscoff month by month

Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences