The temperatures in Viterbo in September are comfortable with low of 16°C and and high up to 26°C.
You can expect about 3 to 8 days of rain in Viterbo 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 Viterbo in September 2026.
If you’re planning to visit Viterbo in the near future, we highly recommend that you review the 14 day weather forecast for Viterbo before you arrive.
Temperatures
26° / 16°
Rainy Days
4
Snowy Days
0
Dry Days
26
Rainfall
106
mm
Sun Hours
11.5
Hrs
