Click on a day for an hourly weather forecast
The temperatures in Seinajoki in August are usually low and can range between 11°C and 20°C.
You can expect rain for roughly half of the month of August in Seinajoki. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in Seinajoki in August 2026.
If you’re planning to visit Seinajoki in the near future, we highly recommend that you review the 14 day weather forecast for Seinajoki before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -5° / -9° | 3 | 7 | 21 | 50 mm | Awful | Seinajoki in January |
| February | -4° / -9° | 3 | 6 | 20 | 44 mm | Awful | Seinajoki in February |
| March | 0° / -6° | 4 | 8 | 19 | 47 mm | Awful | Seinajoki in March |
| April | 6° / -1° | 7 | 14 | 10 | 56 mm | Awful | Seinajoki in April |
| May | 14° / 5° | 7 | 22 | 2 | 76 mm | Bad | Seinajoki in May |
| June | 19° / 9° | 7 | 23 | 0 | 89 mm | Ok | Seinajoki in June |
| July | 22° / 12° | 8 | 23 | 0 | 110 mm | Ok | Seinajoki in July |
| August | 20° / 11° | 8 | 23 | 0 | 132 mm | Ok | Seinajoki in August |
| September | 14° / 7° | 6 | 23 | 0 | 74 mm | Good | Seinajoki in September |
| October | 7° / 2° | 8 | 18 | 5 | 86 mm | Awful | Seinajoki in October |
| November | 2° / -1° | 8 | 11 | 11 | 80 mm | Awful | Seinajoki in November |
| December | -2° / -6° | 5 | 6 | 20 | 63 mm | Awful | Seinajoki in December |