Click on a day for an hourly weather forecast
The temperatures in Terni in September are comfortable with low of 12°C and and high up to 27°C.
You can expect about 3 to 8 days of rain in Terni 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 Terni in September 2026.
If you’re planning to visit Terni in the near future, we highly recommend that you review the 14 day weather forecast for Terni before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 10° / -1° | 6 | 25 | 1 | 83 mm | Ok | Terni in January |
| February | 11° / 0° | 5 | 21 | 2 | 88 mm | Bad | Terni in February |
| March | 15° / 2° | 5 | 26 | 0 | 79 mm | Good | Terni in March |
| April | 19° / 5° | 5 | 25 | 0 | 68 mm | Good | Terni in April |
| May | 22° / 8° | 8 | 23 | 0 | 98 mm | Ok | Terni in May |
| June | 27° / 11° | 6 | 24 | 0 | 82 mm | Perfect | Terni in June |
| July | 32° / 14° | 4 | 27 | 0 | 57 mm | Good | Terni in July |
| August | 32° / 15° | 3 | 28 | 0 | 46 mm | Good | Terni in August |
| September | 27° / 12° | 4 | 26 | 0 | 68 mm | Perfect | Terni in September |
| October | 21° / 8° | 3 | 28 | 0 | 67 mm | Good | Terni in October |
| November | 16° / 5° | 6 | 24 | 0 | 99 mm | Good | Terni in November |
| December | 11° / 1° | 4 | 26 | 1 | 95 mm | Ok | Terni in December |