Click on a day for an hourly weather forecast
The temperatures in Mikkeli in September are quite cold with temperatures between 8°C and 14°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Mikkeli 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 Mikkeli in September 2025.
If you’re planning to visit Mikkeli in the near future, we highly recommend that you review the 14 day weather forecast for Mikkeli before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -6° / -9° | 4 | 3 | 26 | 69 mm | Awful | Mikkeli in January |
| February | -4° / -9° | 3 | 3 | 23 | 58 mm | Awful | Mikkeli in February |
| March | -1° / -6° | 5 | 5 | 22 | 56 mm | Awful | Mikkeli in March |
| April | 6° / -1° | 6 | 12 | 13 | 55 mm | Awful | Mikkeli in April |
| May | 15° / 6° | 6 | 23 | 2 | 66 mm | Ok | Mikkeli in May |
| June | 19° / 10° | 6 | 24 | 0 | 75 mm | Good | Mikkeli in June |
| July | 22° / 13° | 6 | 25 | 0 | 94 mm | Good | Mikkeli in July |
| August | 20° / 12° | 6 | 25 | 0 | 86 mm | Good | Mikkeli in August |
| September | 14° / 8° | 6 | 24 | 0 | 79 mm | Good | Mikkeli in September |
| October | 7° / 2° | 8 | 15 | 7 | 83 mm | Awful | Mikkeli in October |
| November | 2° / -1° | 8 | 9 | 14 | 76 mm | Awful | Mikkeli in November |
| December | -3° / -6° | 6 | 3 | 24 | 76 mm | Awful | Mikkeli in December |