Click on a day for an hourly weather forecast
The temperatures in Boulogne Sur Mer in September are usually low and can range between 13°C and 18°C.
You can expect about 3 to 8 days of rain in Boulogne Sur Mer 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 Boulogne Sur Mer in September 2026.
If you’re planning to visit Boulogne Sur Mer in the near future, we highly recommend that you review the 14 day weather forecast for Boulogne Sur Mer before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 7° / 4° | 10 | 17 | 4 | 122 mm | Awful | Boulogne Sur Mer in January |
| February | 7° / 4° | 9 | 16 | 3 | 103 mm | Awful | Boulogne Sur Mer in February |
| March | 10° / 5° | 7 | 23 | 1 | 83 mm | Bad | Boulogne Sur Mer in March |
| April | 12° / 7° | 4 | 26 | 0 | 59 mm | Ok | Boulogne Sur Mer in April |
| May | 15° / 9° | 5 | 26 | 0 | 81 mm | Good | Boulogne Sur Mer in May |
| June | 17° / 12° | 6 | 24 | 0 | 102 mm | Good | Boulogne Sur Mer in June |
| July | 19° / 14° | 6 | 25 | 0 | 91 mm | Good | Boulogne Sur Mer in July |
| August | 20° / 15° | 6 | 25 | 0 | 114 mm | Good | Boulogne Sur Mer in August |
| September | 18° / 13° | 5 | 25 | 0 | 88 mm | Good | Boulogne Sur Mer in September |
| October | 15° / 11° | 8 | 23 | 0 | 128 mm | Ok | Boulogne Sur Mer in October |
| November | 11° / 8° | 9 | 20 | 0 | 142 mm | Bad | Boulogne Sur Mer in November |
| December | 8° / 6° | 10 | 19 | 2 | 151 mm | Awful | Boulogne Sur Mer in December |