September weather forecastViana, Spain
September
Weather in September
September, the first month of the autumn in Viana, is still a warm month, with an average temperature fluctuating between 12.1°C (53.8°F) and 24.4°C (75.9°F).Temperature
The shift from August to September coincides with a small decrease in the average high-temperature, down to a still warm 24.4°C (75.9°F) from a moderately hot 28.3°C (82.9°F). Throughout September nights, a significant departure from daytime temperatures, with an average low of 12.1°C (53.8°F), is recognized in Viana.Humidity
In September, the average relative humidity is 65%.Rainfall
September is the month with the least rainfall in Viana. Rain falls for 7.7 days and accumulates 10mm (0.39") of precipitation.Snowfall
In Viana, snow does not fall in April through November.Daylight
In Viana, Spain, the average length of the day in September is 12h and 29min.On the first day of September in Viana, sunrise is at 07:35 and sunset at 20:43. On the last day of the month, sunrise is at 08:06 and sunset at 19:52 CEST.
Sunshine
The average sunshine in September is 9.3h.UV index
The average daily maximum UV index in September in Viana, Spain, is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for the average person.Note: In September, the maximum UV index of 5 suggests these recommendations:
Exercise prevention - Protecting skin and eyes from harm is required. The Sun is most powerful around mid-day, so it's a good practice to reduce direct exposure. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Viana, Spain
- Average high temperature in September: 24.4°C
The warmest month (with the highest average high temperature) is August (28.3°C).
The month with the lowest average high temperature is January (8.8°C).
- Average low temperature in September: 12.1°C
The month with the highest average low temperature is August (14.7°C).
The coldest month (with the lowest average low temperature) is February (1.8°C).
Average pressure in September
Viana, Spain
- Average pressure in September: 1018.3mbar
The month with the highest atmospheric pressure is December (1022.5mbar).
The month with the lowest atmospheric pressure is April (1015.4mbar).
Average wind speed in September
Viana, Spain
- Average wind speed in September: 9km/h
The windiest month (with the highest average wind speed) is February (13.3km/h).
The calmest month (with the lowest average wind speed) is September (9km/h).
Average humidity in September
Viana, Spain
- Average humidity in September: 65%
The month with the highest relative humidity is January (78%).
The month with the lowest relative humidity is August (62%).
Average rainfall in September
Viana, Spain
- Average rainfall in September: 10mm
The wettest month (with the highest rainfall) is November (37mm).
The driest month (with the least rainfall) is September (10mm).
Average rainfall days in September
Viana, Spain
- Average rainfall days in September: 7.7 days
The month with the highest number of rainy days is April (14.4 days).
The month with the least rainy days is August (6.7 days).
Average snowfall in September
Viana, Spain
- Average snowfall in September: 0mm
The month with the highest snowfall is February (23mm).
The months with the least snowfall are April, May, June, July, August, September, October and November (0mm).
Average snowfall days in September
Viana, Spain
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.9 days).
The months with the least snowfall days are May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Viana, Spain
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is July (Average sunshine: 11h and 18min).
The month with the least sunshine is November (Average sunshine: 6h and 0min).
Average sunshine days in September
Viana, Spain
- Average sunshine days in September: 18.3 days
The month with the most sunshine days is August (20.1 days).
The months with the least sunshine days are April and May (11.8 days).
Average UV index in September
Viana, Spain
- Average UV index in September: 5
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is November (UV index 2).
Average cloud cover in September
Viana, Spain
- Average cloud cover in September: 23
The months with the most cloud cover are January and November (Cloud cover 40).
The month with the least cloud cover is August (Cloud cover 19).
Average visibility in September
Viana, Spain
- Average visibility in September: 10km
The months with the highest visibility are June, July, August, September, October and December (10km).
The months with the lowest visibility are January, February, March, April, May and November (9km).
