Sea temperature in Portugal
Live water temperatures and swimming conditions across 255 beaches on the Portugal coast.
Best time to swim in Portugal
The sea in Portugal peaks in August, when the water averages around 21°C.
The main swimming season runs from July – September, when surface temperatures stay comfortable for extended sessions.
On average, 3 months a year sit above 20°C — the threshold most swimmers describe as pleasant without a wetsuit.
Shoulder months like June and October are noticeably cooler but often quieter, with fewer crowds and steadier weather.
Outside peak season the water drops toward 14°C, so a 3/2mm shorty or full wetsuit makes long swims much more comfortable.
The coldest month is typically February at around 14°C, when cold-water swimmers dominate the coast.
Portugal sea temperature history
Long-term climatology for Portugal shows an annual mean sea temperature of 18°C, ranging from 14°C in winter to 21°C at the summer peak.
The seasonal swing is roughly 7°C between the coldest and warmest month — a useful yardstick when comparing years or checking whether the current sea is running above or below average.
Recent decades have trended slightly warmer at Portugal, in line with regional sea-surface temperature records for the wider basin.
Monthly averages below are drawn from multi-decadal climatology and are updated as new observations arrive.
Values are area averages; individual beaches vary by exposure and depth.
Portugal sea temperature: frequently asked questions
What is the warmest month to swim in Portugal?
August is the warmest month in Portugal, when the sea averages about 21°C. Late-season warmth often persists a few weeks after peak.
When is the sea coldest in Portugal?
The coldest month in Portugal is typically February, when the water averages around 14°C. Cold-water swimmers and surfers dominate this period.
When can you swim in Portugal without a wetsuit?
The main swimming season in Portugal runs from July – September — about 3 months a year when the sea sits above 20°C, the level most swimmers describe as pleasant without a wetsuit.
Do I need a wetsuit in Portugal?
Outside peak summer the water in Portugal drops toward 14°C, so a 3/2mm shorty or full wetsuit makes long swims much more comfortable. In peak months most swimmers go without.
What is the average sea temperature in Portugal?
The long-term annual mean sea temperature in Portugal is about 18°C, based on multi-decadal climatology of the surrounding waters.
How do I check the current sea temperature in Portugal?
The live reading at the top of this page shows the current sea temperature in Portugal, updated hourly from marine buoy and satellite data. The 7-day forecast covers water, air, waves, wind and UV for the week ahead.
Coastal regions of Portugal
Region hubs with live sea temperatures, swim conditions and a beach directory.