Weather in Lisbon in August 2025
- August is usually the hottest month of the year in Lisbon;
- August is usually the driest month of the year in Lisbon
Average weather
Average temperature in Lisbon in August
Going from a maximum of +36°C during the day to a minimum of +17°C during the night, the temperature in August averages around +30°C.
The average maximum temperature goes up 0% by the end of the month, compared with the beginning of the month, from +29°C to +29°C.
Is Lisbon warm or cold in August?
Lisbon is typically warm in August.
Maximum temperatures go up compared to the previous month from +26°C to +27°C. The minimum temperature also goes up from +18°C to +18°C.
It’s generally warm, but pack a long-sleeve shirt for evenings.
August is the hottest month in Lisbon, here is the comparison with other months:
Water temperature in Lisbon in August
Water in Lisbon in August is Fresh. It varies from +17°C to +22°C, with an average of +20°C. The air temperature averaging +27°C is higher than the water temperature.
The water temperature in August is one of the warmest of the entire year:
Can you swim in Lisbon in August?
Climate in Lisbon in August
| July | August | September | ||||
|---|---|---|---|---|---|---|
| Avg. temperature | ||||||
| +26°C | +27°C | +25°C | ||||
| Min. temperature | ||||||
| +15°C | +15°C | +13°C | ||||
| Max. temperature | ||||||
| +40°C | +41°C | +39°C | ||||
| Rainfall | ||||||
| 2 mm | 4 mm | 34 mm | ||||
| Wind | ||||||
| 4 m/s | 4 m/s | 3 m/s | ||||
| Avg. water temperature | ||||||
| +19°C | +20°C | +20°C | ||||
| Humidity | ||||||
| 66% | 65% | 67% | ||||
| Air pressure | ||||||
| 1016 HPa | 1016 HPa | 1016 HPa | ||||
| Sunny days | ||||||
| 20 | 22 | 18 | ||||
| Cloudy days | ||||||
| 9 | 7 | 6 | ||||
| Rainy days | ||||||
| 2 | 2 | 5 | ||||
| Snowy days | ||||||
| 0 | 0 | 0 | ||||
August weather is still as great as in July. It’s getting warmer as August arrives. The average maximum temperature goes up from +26°C to +27°C during the day. Prepare for more rain. Average rainfall goes from 2 mm to 4 mm. It feels drier, as humidity decreases from 66% to 65%. The average wind speed doesn’t change much during August, staying around 4 m/s. The good news is there are likely to be more sunny days in August, from 20 to 22.
September brings much the same weather, it remains great.
Wind
The average wind speed is 6 m/s getting up to 13 m/s which is a medium breeze. You can feel it, especially getting out of the water.
The average wind speed in Lisbon is gradually decreasing during August, going from 8 m/s to 7 m/s over the course of the month.
Rain
How was the weather last August in Lisbon?
Climate Change over Years
The climate in Lisbon in August has not changed much over the last 43 years.
The average temperature was the lowest in 1979 (+18°C) and the highest in 2017 (+22°C). The driest year was 1992 with only 298 mm of rainfall, and the wettest year was 2022 with 2338 mm.
FAQ
Is August a good time to visit Lisbon?
Can you sunbathe in Lisbon in August?
Can you swim in Lisbon in August?
Is Lisbon rainy in August?
Is it sunny in Lisbon in August?
Other cities in Portugal
Monthly weather in Lisbon
Source of the data
For this page, we’ve looked at the typical weather in Lisbon, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.