Click on a day for an hourly weather forecast
The temperatures in Joensuu in September are quite cold with temperatures between 7°C and 13°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Joensuu 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.
Please note that Joensuu can expect a few days of snow in September.
Our weather forecast can give you a great sense of what weather to expect in Joensuu in September 2025.
If you’re planning to visit Joensuu in the near future, we highly recommend that you review the 14 day weather forecast for Joensuu before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -7° / -11° | 2 | 4 | 25 | 61 mm | Awful | Joensuu in January |
| February | -6° / -11° | 2 | 3 | 24 | 60 mm | Awful | Joensuu in February |
| March | -2° / -7° | 4 | 4 | 23 | 61 mm | Awful | Joensuu in March |
| April | 4° / -1° | 6 | 10 | 15 | 55 mm | Awful | Joensuu in April |
| May | 13° / 5° | 7 | 22 | 3 | 74 mm | Awful | Joensuu in May |
| June | 18° / 9° | 6 | 23 | 0 | 95 mm | Good | Joensuu in June |
| July | 21° / 13° | 8 | 23 | 0 | 125 mm | Ok | Joensuu in July |
| August | 19° / 11° | 7 | 24 | 0 | 122 mm | Ok | Joensuu in August |
| September | 13° / 7° | 7 | 22 | 1 | 102 mm | Bad | Joensuu in September |
| October | 6° / 2° | 8 | 15 | 8 | 83 mm | Awful | Joensuu in October |
| November | 1° / -2° | 8 | 7 | 16 | 82 mm | Awful | Joensuu in November |
| December | -4° / -7° | 4 | 3 | 25 | 70 mm | Awful | Joensuu in December |