Praia de Sesimbra — Sea temperature now
Lisbon Coast family beach.
Mild water with a light chop and a light breeze — good swimming conditions.
Location
Praia de Sesimbra on the map, with nearby beaches and live sea temperatures.
7-day forecast
Water, air, waves, wind and UV outlook for the week ahead.
Monthly sea temperature averages
Typical year-round water temperature, based on regional climatology.
Best time to swim in Praia de Sesimbra
The sea in Praia de Sesimbra 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.
Praia de Sesimbra sea temperature history
Long-term climatology for Praia de Sesimbra 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 Praia de Sesimbra, 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.
Praia de Sesimbra sea temperature: frequently asked questions
What is the warmest month to swim in Praia de Sesimbra?
August is the warmest month in Praia de Sesimbra, when the sea averages about 21°C. Late-season warmth often persists a few weeks after peak.
When is the sea coldest in Praia de Sesimbra?
The coldest month in Praia de Sesimbra is typically February, when the water averages around 14°C. Cold-water swimmers and surfers dominate this period.
When can you swim in Praia de Sesimbra without a wetsuit?
The main swimming season in Praia de Sesimbra 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 Praia de Sesimbra?
Outside peak summer the water in Praia de Sesimbra 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 Praia de Sesimbra?
The long-term annual mean sea temperature in Praia de Sesimbra is about 18°C, based on multi-decadal climatology of the surrounding waters.
How do I check the current sea temperature in Praia de Sesimbra?
The live reading at the top of this page shows the current sea temperature in Praia de Sesimbra, updated hourly from marine buoy and satellite data. The 7-day forecast covers water, air, waves, wind and UV for the week ahead.
Year-round sea temperature
Best swim months: Jul – Aug – Sep
| Month | Sea | Comfort |
|---|---|---|
| Jan | 15°C | Bracing |
| Feb | 14°C | Bracing |
| Mar | 15°C | Bracing |
| Apr | 16°C | Bracing |
| May | 17°C | Bracing |
| Jun | 19°C | Pleasant |
| Jul | 20°C | Pleasant |
| Aug ⭐ | 21°C | Pleasant |
| Sep | 21°C | Pleasant |
| Oct | 19°C | Pleasant |
| Nov | 18°C | Pleasant |
| Dec | 16°C | Bracing |