Lisbon weather in August
Lisbon averages 29°C by day and 19°C at night in August, with the sea at 20°C and about 1 mm of rain in the month. It cools by about 2°C into September.
Day
29°C
Night
19°C
Sea
20°C
Rain
1 mm
Flight from London
2½h
What August feels like
August is hot in Lisbon: proper beach weather.
The sea is 20°C: refreshing, and chilly for most people after a few minutes.
It is dry: only about 1 mm of rain in the month.
That is 6°C warmer than an average August day in London.
Of the 56 sun destinations we track, Lisbon is the #38 warmest in August, and #18 of 23 within 5½ hours of the UK.
Going to Lisbon in August?
Share the TikToks and Instagram Reels you've saved for Lisbon to Dream Trip. It finds the places, pins them on a map and builds your days around them.
Want it warmer in August?
These are hotter than Lisbon this month for at most an hour and a half more flying:
Lisbon weather by month
August is highlighted. Compare with July and September, or see the full year in Lisbon.
Lisbon in August: quick answers
Is Lisbon hot in August?
August is hot in Lisbon: proper beach weather. Average highs are 29°C and lows 19°C.
Can you swim in Lisbon in August?
The sea is 20°C: refreshing, and chilly for most people after a few minutes.
Does it rain in Lisbon in August?
It is dry: only about 1 mm of rain in the month.
What is the warmest month in Lisbon?
August, at an average high of 29°C. The coolest is January at 15°C.
How long is the flight to Lisbon from the UK?
About 2½h direct from London, estimated from the 1,571 km distance. Check your airline for exact times.
Still choosing? See where is hot in August for every destination ranked by temperature, sea and flight time.
How we measured this
Averages of every day in August from 2016 to 2025, from the Open-Meteo historical weather archive (ECMWF ERA5 reanalysis). Sea temperature is the 2023 to 2025 average from the Open-Meteo marine archive. Rain is the average monthly total. Reanalysis describes an area about 25 km across, so sheltered resorts can run a degree or two warmer. Flight time is a distance-based estimate from London Heathrow.
Planning Lisbon in August?
Save the restaurants, beaches and views you find on TikTok and Instagram for Lisbon straight to a map, then let Dream Trip turn them into a day-by-day plan.
