September weather forecastOlhão, Portugal
September
Weather in September
September in Olhão signifies the beginning of a gentle transition from the warm summer to the cooler autumn months. Compared to August, there is a notable shift in the average temperature, signaling cooler days. Rainfall also sees a slight increase from 1mm (0.04") to 3mm (0.12"), marking the end of the summer drought. The decrease in temperature doesn't deter beach lovers as the sea temperature remains relatively warm. As the summer crowds recede, it is an opportune time for a tranquil retreat into the city’s picturesque surroundings.Temperature
Olhão measures an average high-temperature of a still moderately hot 24.8°C (76.6°F) in September, nearly consistent with the preceding month. Olhão's temperature during September nights registers a minor decrease to an average low of 20°C (68°F).Humidity
In Olhão, the average relative humidity in September is 68%.Rainfall
In Olhão, in September, during 2.7 rainfall days, 3mm (0.12") of precipitation is typically accumulated. Throughout the year, in Olhão, there are 54.1 rainfall days, and 109mm (4.29") of precipitation is accumulated.Sea temperature
In September, the average sea temperature in Olhão is 21.6°C (70.9°F).Note: Most individuals do not find swimming at 21.6°C (70.9°F) to be enjoyable. As the water temperature declines below 21°C (69.8°F), maintaining control over one's breathing becomes harder.
Daylight
In September, the average length of the day is 12h and 25min.On the first day of September, sunrise is at 07:02 and sunset at 19:59. On the last day of the month, sunrise is at 07:26 and sunset at 19:16 WEST.
Sunshine
The average sunshine in September in Olhão, Portugal, is 9.6h.UV index
The months with the highest UV index are May through September, with an average maximum UV index of 6. A UV Index estimate of 6 to 7 represents a high health risk from exposure to the Sun's UV rays for average individuals.Note: An average maximum UV index of 6 in September leads to these recommendations:
Undertake precautions and comply with sun safety standards. Protection from skin and eye injury is vital. Limit your exposure to the sun's UV radiation, which is strongest between 10 a.m. and 4 p.m., and note that parasols or canopies may not provide full sun protection. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes. Caution! The mirror effect of sand and water ups the UV radiation strength.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Olhão, Portugal
- Average high temperature in September: 24.8°C
The warmest month (with the highest average high temperature) is August (27.1°C).
The month with the lowest average high temperature is January (15.1°C).
- Average low temperature in September: 20°C
The month with the highest average low temperature is August (20.8°C).
The coldest month (with the lowest average low temperature) is February (11.2°C).
Average pressure in September
Olhão, Portugal
- Average pressure in September: 1016.4mbar
The month with the highest atmospheric pressure is December (1022.5mbar).
The months with the lowest atmospheric pressure are April and August (1015.4mbar).
Average wind speed in September
Olhão, Portugal
- Average wind speed in September: 12.7km/h
The windiest months (with the highest average wind speed) are February and March (19km/h).
The calmest month (with the lowest average wind speed) is September (12.7km/h).
Average humidity in September
Olhão, Portugal
- Average humidity in September: 68%
The month with the highest relative humidity is April (74%).
The month with the lowest relative humidity is August (62%).
Average rainfall in September
Olhão, Portugal
- Average rainfall in September: 3mm
The wettest month (with the highest rainfall) is November (19mm).
The driest months (with the least rainfall) are June, July and August (1mm).
Average rainfall days in September
Olhão, Portugal
- Average rainfall days in September: 2.7 days
The month with the highest number of rainy days is April (8.2 days).
The month with the least rainy days is August (0.8 days).
Average sea temperature in September
Olhão, Portugal
- Average sea temperature in September: 21.6°C
The best month for swimming (with the highest average sea temperature) is August (22.1°C).
The coldest month (with the lowest average sea temperature) is March (15.9°C).
Average daylight in September /
Average sunshine in September
Olhão, Portugal
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in September: 9h and 36min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 6h and 6min).
Average sunshine days in September
Olhão, Portugal
- Average sunshine days in September: 26.5 days
The month with the most sunshine days is July (29.8 days).
The month with the least sunshine days is April (20.3 days).
Average UV index in September
Olhão, Portugal
- Average UV index in September: 6
The months with the highest UV index are May, June, July, August and September (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 4).
Average cloud cover in September
Olhão, Portugal
- Average cloud cover in September: 13
The month with the most cloud cover is January (Cloud cover 30).
The month with the least cloud cover is July (Cloud cover 4).
Average visibility in September
Olhão, Portugal
- Average visibility in September: 10km
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
