Porto weather in August
Temperature, sea and sunshine in August: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in August
Excellent
Best time to visit: May – September
What is the weather like in Porto in August?
In August, Porto is warm: daytime highs average 26 °C, and nights cool down to about 17 °C. The sea averages 17.3 °C – bracing, so a wetsuit helps for longer swims. With around 10 hours of sunshine a day, there is plenty of sun. Rain is rare: about 4 days bring 24 mm in total. On about 5 days the thermometer climbs to 30 °C or more. All in all, August is an excellent month for a holiday in Porto.
August compared
How the weather changes from July to September. Tap a month to open it.
| JulyJul | AugustAug | SeptemberSep | |
|---|---|---|---|
| Score | 100 | 100 | 92 |
| Day | 26° | 26° | 24° |
| Night | 17° | 17° | 16° |
| Sea | 17° | 17° | 17° |
| Sun | 11 h | 10 h | 9 h |
| Rain days | 4 | 4 | 7 |
More details for August
- Daylight
- 13 h 52 min06:43 – 20:35
- UV index
- 8 · very highclear sky, noon (estimate)
- Muggy days
- 5 daysdew point 18 °C or more
- Wind
- 17 km/haverage daily peak
- Cloud cover
- 35 %on average
- Hot days
- 5 days30 °C or more
- Time zone
- UTC+1Europe/Lisbon
How the score comes together
- Temperatureweight 50 %100 %
- Sunshineweight 20 %100 %
- Few rainy daysweight 30 %100 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in August
- Wetsuit for longer swims
- Sunscreen
- Sunglasses & sun hat
- Light, breathable clothes
Porto in August: quick answers
Is Porto hot in August?
Warm rather than hot: in August, daytime highs in Porto average 26 °C and nights cool to about 17 °C. On about 5 days the thermometer climbs to 30 °C or more.
Can you swim in Porto in August?
Only if you don't mind cold water: in August the sea averages just 17.3 °C. Comfortable swimming temperatures are not reached at any time of year.
Does it rain much in Porto in August?
Rain is rare: about 4 days bring 24 mm in total.
Porto month by month
The whole year in PortoAll destinations: Portugal
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, GeoNames (CC BY 4.0)