August weather forecast
Lisbon, Portugal

Riding the wave of summer, August in Lisbon continues with conditions similar to July. With the temperature reaching a peak of 28.3°C (82.9°F), this is the only month to rival July in terms of warmth. The rain remains a scarce occurrence, and tourists can enjoy clear blue skies above. However, the UV index does drop slightly, offering a mild respite for those spending prolonged hours under the sun. Despite this, daytime temperatures remain high, promoting beach activities and water sports.

Temperature

Lisbon registers the highest average temperatures during the month of August, with peaks of 28.3°C (82.9°F) and lows of 18.6°C (65.5°F).

Rainfall

In August, the rain falls for 2 days. Throughout August, 6mm (0.24") of precipitation is accumulated. Throughout the year, in Lisbon, there are 112 rainfall days, and 774mm (30.47") of precipitation is accumulated.

Sea temperature

In August, the average sea temperature is 19.6°C (67.3°F).
Note: For swimming, a surface water temperature of 19.6°C (67.3°F) is not enjoyable for the majority. It is not considered safe, as controlling breathing becomes progressively more difficult as water temperature decreases below 21°C (69.8°F).

Daylight

The average length of the day in August in Lisbon is 13h and 38min.
On the first day of the month, sunrise is at 06:38 and sunset at 20:47. On the last day of August, in Lisbon, Portugal, sunrise is at 07:05 and sunset at 20:08 WEST.

Sunshine

The months with the most sunshine in Lisbon, Portugal, are July and August, with an average of 11h of sunshine.

UV index

The average daily maximum UV index in August in Lisbon is 8. A UV Index estimate of 8 to 10 represents a very high health risk from unsafe exposure to UV radiation for the average person.
Note: A maximum high UV index of 8 in August translates into the following recommendations:
Stay protected; otherwise, skin and eyes can suffer rapid damage. Limit direct sun exposure especially between 10 a.m. and 4 p.m., when UV radiation is at its peak. However, keep in mind that shade structures may not provide full sun protection. It's wise to wear UVA and UVB-blocking sunglasses when the sun shines brightly.