Ireland: where to swim in April?
Ireland, in April: the sea is at 10.0 °C on average along the coast, from 9.2 °C to 10.6 °C depending on the spot. Where the water is warmest (10.6 °C), it is cold. You can swim, but the cold bites quickly: plan a short swim, or wear a wetsuit.
Sea temperature, month by month
| Month | Average temperature | Depending on the spot | Where it is warmest |
|---|---|---|---|
| January | 9.9 °C | 9.2 °C – 10.4 °C | cold |
| February | 9.4 °C | 8.5 °C – 10.2 °C | cold |
| March | 9.4 °C | 8.5 °C – 10.2 °C | cold |
| April | 10.0 °C | 9.2 °C – 10.6 °C | cold |
| May | 11.5 °C | 10.8 °C – 12.1 °C | cold |
| June | 13.6 °C | 12.9 °C – 14.5 °C | cold |
| July | 15.2 °C | 14.2 °C – 16.4 °C | cool |
| August | 15.8 °C | 14.9 °C – 16.5 °C | cool |
| September | 15.0 °C | 14.2 °C – 15.7 °C | cool |
| October | 13.7 °C | 12.9 °C – 14.3 °C | cold |
| November | 12.2 °C | 11.6 °C – 12.8 °C | cold |
| December | 10.8 °C | 10.4 °C – 11.2 °C | cold |
Compared with March, the water warms up by 0.6 °C in April. The warmest month: August (15.8 °C). The coldest: February (9.4 °C).
Nearby, in April
- United Kingdom 8.5 °C · very cold
- Netherlands 8.0 °C · very cold
- France 13.0 °C · cool
- Denmark 6.4 °C · very cold
- Germany 6.7 °C · very cold
- Portugal 16.0 °C · cool
And right now?
For the temperature measured right now, station by station and to the hour: Ireland: water temperature
Frequently asked questions
What is the sea temperature in April?
Ireland, in April: 10.0 °C on average along the coast, from 9.2 °C in the coolest waters to 10.6 °C in the warmest (average of the years 2011 to 2025).
Can you swim in April?
Where the water is warmest (10.6 °C), it is cold. You can swim, but the cold bites quickly: plan a short swim, or wear a wetsuit.
What is the best month for swimming?
The water is warmest in August (15.8 °C on average) and coldest in February (9.4 °C). Even where it is warmest, the water never reaches 20 °C in any month; the three warmest months are: August, July, September.
Where is the water warmest in April?
The warmest in April: United Kingdom (8.5 °C), Netherlands (8.0 °C), France (13.0 °C). The coolest: Portugal (16.0 °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.