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The temperatures in Rimouski in September are quite cold with temperatures between 9°C and 15°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Rimouski 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 Rimouski in September 2025.
If you’re planning to visit Rimouski in the near future, we highly recommend that you review the 14 day weather forecast for Rimouski before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -8° / -14° | 3 | 5 | 24 | 98 mm | Awful | Rimouski in January |
| February | -7° / -13° | 3 | 4 | 22 | 81 mm | Awful | Rimouski in February |
| March | -3° / -8° | 7 | 5 | 21 | 101 mm | Awful | Rimouski in March |
| April | 4° / -1° | 8 | 8 | 14 | 135 mm | Awful | Rimouski in April |
| May | 12° / 5° | 8 | 23 | 1 | 108 mm | Bad | Rimouski in May |
| June | 17° / 10° | 7 | 23 | 0 | 115 mm | Ok | Rimouski in June |
| July | 21° / 13° | 7 | 24 | 0 | 121 mm | Ok | Rimouski in July |
| August | 20° / 13° | 7 | 24 | 0 | 117 mm | Ok | Rimouski in August |
| September | 15° / 9° | 6 | 24 | 0 | 114 mm | Good | Rimouski in September |
| October | 9° / 4° | 9 | 18 | 4 | 147 mm | Awful | Rimouski in October |
| November | 3° / -1° | 6 | 12 | 12 | 121 mm | Awful | Rimouski in November |
| December | -4° / -8° | 5 | 7 | 19 | 115 mm | Awful | Rimouski in December |