The temperatures in Viana do Castelo in September are comfortable with low of 16°C and and high up to 23°C.
You can expect about 3 to 8 days of rain in Viana do Castelo 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 Viana do Castelo in September 2025.
If you’re planning to visit Viana do Castelo in the near future, we highly recommend that you review the 14 day weather forecast for Viana do Castelo before you arrive.
Temperatures
23° / 16°
Rainy Days
3
Snowy Days
0
Dry Days
27
Rainfall
26
mm
Sun Hours
2.9
Hrs