Viana do Castelo Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Viana do Castelo.
Climate overview of Viana do Castelo
Viana do Castelo, Norte Region, Portugal, has a moderate seasonal temperature range, with August reaching 24°C (75°F) and January cooling to 14°C (57°F).
The city has a wet climate, receiving around 1649 mm (65 in) of rainfall per year. Despite the high annual total, it has a distinct rainy season from October to January. November is the wettest month. Sunshine peaks in July, when the city sees around 10.2 hours of sunshine per day.
Viana do Castelo Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Viana do Castelo - and find the best time to visit.
Monthly Temperature in Viana do Castelo
The climate in Viana do Castelo experiences moderate temperature changes, with mild shifts between seasons. On average, daytime temperatures range from a comfortable 24°C (75°F) in August to a moderate 14°C (57°F) in January.
Nighttime temperatures range from 16°C (61°F) in August to 8°C (46°F) in January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Viana do Castelo
Viana do Castelo is known for its substantial rainfall, with annual precipitation reaching 1649 mm (65 in). The seasons in Viana do Castelo bring significant changes in precipitation. The wettest month, November, receives heavy rainfall, with an average of 225 mm (8.9 in) of precipitation. This rainfall is distributed across 17 rainy days.
In contrast, the driest month, July, experiences much less rainfall, totaling 29 mm (1.1 in) over 7 rainy days. These distinct seasonal differences provide diverse experiences throughout the year. For more details, please visit our Viana do Castelo Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Sunshine Hours in Viana do Castelo
In Viana do Castelo, summer days are longer and more sunny, with daily sunshine hours peaking at 10.2 hours in July. As the darker season arrives, the brightness of the sun becomes less. January sees a soft sun for only 4.1 hours per average day.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Humidity in Viana do Castelo by Month
The relative humidity is high throughout the year in Viana do Castelo.
The city experiences its highest humidity in January, reaching 81%. In July, the humidity drops to its lowest level at 73%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Best Time to Visit Viana do Castelo
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
- Best overall: June, July, August and September
- Warmest weather: July, August and September
- Most sunshine: July and August
- Fewest rainy days: July and August
- Seasonal pattern: A distinct rainy season from October to January
Frequently asked questions about the climate in Viana do Castelo
What is the best time to visit Viana do Castelo?
June, July, August and September typically offer the most optimal weather in Viana do Castelo. In contrast, January, November and December tend to have less optimal conditions. Viana do Castelo has a distinct rainy season from October to January.
What temperatures can I expect in Viana do Castelo?
Daytime highs range from 14°C (57°F) in January to 24°C (75°F) in August. Nighttime lows range from 8°C (46°F) to 16°C (61°F).
How much rain does Viana do Castelo get?
Annual rainfall is around 1649 mm (65 in). November is the wettest month with 225 mm (8.9 in), while July is the driest with 29 mm (1.1 in).
How sunny is Viana do Castelo?
Viana do Castelo receives around 2,465 hours of sunshine per year. July is the sunniest month with 307 hours, while January is the cloudiest with just 122 hours. Overall, Viana do Castelo enjoys abundant sunshine.
Viana do Castelo 3-Day Forecast
Viana do Castelo 3-Day Forecast
Viana do Castelo on the map
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