Temperatures in September
It's warm in September in Viana do Castelo with an average temperature of 24°C. Temperatures this month range from a low of 21°C to a high of 27°C. At night, you can expect temperatures between 13°C and 17°C.
Max and Min Temperatures per Day
This chart shows the daily maximum and minimum temperatures in degrees Celsius for Viana do Castelo in September. The red line indicates the max temperatures, and the blue line shows the minimums.
Start of September
The month of September starts in Viana do Castelo with warm temperatures, averaging around 25°C during the day and nights close to 16°C. A few showers might pop up in the first days of the month, but the weather remains mostly sunny and dry.
Mid-September
By mid-September, the average daytime temperature drops to around 24°C, with nights close to 16°C. During this part of the month, you can expect regular precipitation, but there’ll also be some sunny days.
End of September
By the end of September, the average daytime temperature in Viana do Castelo will be around 23°C, with nights close to 14°C. A shower might show up, but overall the weather will be dry and sunny.
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Water temperature
The water temperature at Viana do Castelo is 20°C this month. Refreshing if you fancy a swim.
Precipitation in September
In September, there is an average of 76 mm of precipitation, spread over 8 days. The wind speed is around 3 Bft, mostly coming from the Southwest.
The average precipitation chance is 26% per day this month. Though it seems pretty low, the weather’s variable. Some days have higher and others lower precipitation chances, which lowers the average.
Precipitation Chance
This chart shows the daily precipitation chance (in percentages) in September for Viana do Castelo. 0% means it never rained on that day in the past 10 years, and 100% means it rained every day. All values in between represent the average chance of precipitation on that day.
Viana do Castelo in September |
London | ||
|---|---|---|---|
 Average Temperature |
24°C | 20°C | |
 High Temp |
27°C | 22°C | |
| Low Temp |
21°C | 17°C | |
 Total Precipitation |
76 mm | 44 mm | |
| Rainy Days |
8 days | 8 days | |
August
UV index
The UV index is a maximum of 6 this month. That's a moderate to high value on the intensity scale of 1 to 11. Unprotected skin can burn within 15-25 minutes.
Is September a good time to visit Viana do Castelo?
Want nice weather? Then September is a great time to be in Viana do Castelo. You’ll have pleasant temperatures and not too much rain this month.
Temperature records for Viana do Castelo in September
With 36°C, Viana do Castelo hit the highest temperature in the last 10 years in September 2020. The lowest daytime temperature in this month was 16°C in 2018. The extreme night temperatures ranged from a low of 8°C to a high of 22°C.
Check out the climate of Viana do Castelo for all months and discover the best travel time
Curious about the climate in other parts of Portugal? Check out the weather and climate in places like Algarve, Lisbon, Albufeira, or have a look at other destinations in Portugal.
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Daily Temperature in September in Viana do Castelo
This chart shows the average daily temperatures, both day and night, for each day in September in Viana do Castelo, measured in degrees Celsius. The red line represents the maximum temperatures, while the blue line shows the minimums. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, gives an overview of the average daily temperatures during this month.
Daily Precipitation in September in Viana do Castelo
The chart below shows the average daily precipitation in September for Viana do Castelo, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are shown at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that rain is more likely. But it’s still an average, so each day can be different. Based on historical weather data for September, you can expect around 8 days of rain in Viana do Castelo.
Daily UV Index in September in Viana do Castelo
This chart shows the average daily UV index in September in Viana do Castelo, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in September in Viana do Castelo Over the Years
This chart shows the average temperature in September in Viana do Castelo, measured in degrees Celsius, over the past years.
Total Precipitation in September in Viana do Castelo Over the Years
This chart shows the average precipitation in September in Viana do Castelo, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail.
Daily climate in September for Viana do Castelo
Click on a specific day in September for detailed info on the typical weather on that day in Viana do Castelo. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Viana do Castelo
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Average Weather in Viana do Castelo by Month
Click on a month below to see detailed weather info for Viana do Castelo. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
Or check out the climate of Viana do Castelo for all months at once
