Portugal: where to swim in January?
Portugal, in January: the sea is at 15.6 °C on average along the coast, from 14.3 °C to 17.1 °C depending on the spot. Where the water is warmest (17.1 °C), it is cool. Swimming is fine if you like cool water: you get used to it after a few minutes, especially in mild weather.
Sea temperature, month by month
| Month | Average temperature | Depending on the spot | Where it is warmest |
|---|---|---|---|
| January | 15.6 °C | 14.3 °C – 17.1 °C | cool |
| February | 14.9 °C | 13.8 °C – 16.3 °C | cool |
| March | 14.9 °C | 13.8 °C – 16.3 °C | cool |
| April | 16.0 °C | 15.1 °C – 17.2 °C | cool |
| May | 17.2 °C | 16.0 °C – 18.8 °C | cool |
| June | 18.5 °C | 17.4 °C – 20.2 °C | pleasant |
| July | 19.2 °C | 17.9 °C – 21.2 °C | pleasant |
| August | 19.5 °C | 18.1 °C – 21.3 °C | pleasant |
| September | 20.2 °C | 18.4 °C – 22.1 °C | pleasant |
| October | 19.6 °C | 17.5 °C – 21.8 °C | pleasant |
| November | 18.1 °C | 16.5 °C – 19.9 °C | pleasant |
| December | 16.7 °C | 15.0 °C – 18.2 °C | cool |
Compared with December, the water cools down by 1.1 °C in January. The warmest month: September (20.2 °C). The coldest: February (14.9 °C).
Nearby, in January
- France 12.3 °C · cold
- Ireland 9.9 °C · cold
- United Kingdom 8.8 °C · cold
- Netherlands 7.4 °C · very cold
- Germany 4.9 °C · very cold
- Croatia 14.3 °C · cold
And right now?
For the temperature measured right now, station by station and to the hour: Portugal: water temperature
Frequently asked questions
What is the sea temperature in January?
Portugal, in January: 15.6 °C on average along the coast, from 14.3 °C in the coolest waters to 17.1 °C in the warmest (average of the years 2011 to 2025).
Can you swim in January?
Where the water is warmest (17.1 °C), it is cool. Swimming is fine if you like cool water: you get used to it after a few minutes, especially in mild weather.
What is the best month for swimming?
The water is warmest in September (20.2 °C on average) and coldest in February (14.9 °C). Where the water is warmest, it goes above 20 °C in these months: June, July, August, September, October.
Where is the water warmest in January?
The warmest in January: France (12.3 °C), Ireland (9.9 °C), United Kingdom (8.8 °C). The coolest: Croatia (14.3 °C).
Where do these temperatures come from?
These are averages of the sea surface temperature from 2011 to 2025, computed from NOAA satellite images (OISST, one value about every 50 km), in a 100 km strip along the coasts of the main country: distant territories (overseas, remote islands) are not counted. It is an estimate, not a measurement taken at the beach: lakes and rivers are not included.