Click on a day for an hourly weather forecast
The temperatures in Brest in September are usually low and can range between 14°C and 19°C.
You can expect about 3 to 8 days of rain in Brest during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Brest in September 2025.
If you’re planning to visit Brest in the near future, we highly recommend that you review the 14 day weather forecast for Brest before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 10° / 7° | 11 | 20 | 1 | 155 mm | Bad | Brest in January |
| February | 10° / 6° | 9 | 18 | 1 | 134 mm | Bad | Brest in February |
| March | 11° / 7° | 6 | 24 | 0 | 81 mm | Ok | Brest in March |
| April | 13° / 8° | 4 | 26 | 0 | 73 mm | Ok | Brest in April |
| May | 15° / 10° | 4 | 27 | 0 | 63 mm | Good | Brest in May |
| June | 18° / 13° | 4 | 26 | 0 | 74 mm | Good | Brest in June |
| July | 20° / 15° | 5 | 26 | 0 | 75 mm | Good | Brest in July |
| August | 19° / 15° | 5 | 26 | 0 | 86 mm | Good | Brest in August |
| September | 19° / 14° | 4 | 26 | 0 | 59 mm | Good | Brest in September |
| October | 16° / 12° | 7 | 24 | 0 | 126 mm | Ok | Brest in October |
| November | 13° / 10° | 9 | 21 | 0 | 159 mm | Bad | Brest in November |
| December | 11° / 8° | 10 | 21 | 1 | 167 mm | Bad | Brest in December |