Click on a day for an hourly weather forecast
The temperatures in Riihimaki in September are quite cold with temperatures between 8°C and 15°C, warm clothes are a must.
You can expect rain for roughly half of the month of September in Riihimaki. 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 Riihimaki in September 2026.
If you’re planning to visit Riihimaki in the near future, we highly recommend that you review the 14 day weather forecast for Riihimaki before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -3° / -8° | 12 | 14 | 5 | 48 mm | Awful | Riihimaki in January |
| February | -3° / -7° | 10 | 13 | 5 | 41 mm | Awful | Riihimaki in February |
| March | 1° / -5° | 9 | 17 | 5 | 42 mm | Awful | Riihimaki in March |
| April | 8° / 0° | 6 | 22 | 2 | 40 mm | Bad | Riihimaki in April |
| May | 15° / 6° | 8 | 23 | 0 | 57 mm | Ok | Riihimaki in May |
| June | 20° / 10° | 10 | 20 | 0 | 70 mm | Ok | Riihimaki in June |
| July | 22° / 13° | 10 | 21 | 0 | 76 mm | Ok | Riihimaki in July |
| August | 21° / 12° | 10 | 21 | 0 | 70 mm | Ok | Riihimaki in August |
| September | 15° / 8° | 8 | 22 | 0 | 55 mm | Ok | Riihimaki in September |
| October | 8° / 3° | 7 | 24 | 0 | 52 mm | Bad | Riihimaki in October |
| November | 3° / 0° | 8 | 21 | 1 | 47 mm | Bad | Riihimaki in November |
| December | -1° / -5° | 11 | 16 | 4 | 53 mm | Awful | Riihimaki in December |