Castletown Beach Sea Water Temperature
A cool beach on the Irish Sea, warmest around August at about 15°C. Today's reading, 7-day forecast, and monthly averages below.
Castletown Beach water temperature
Wetsuit strongly recommended. Sudden entry may cause cold shock. Suitable only for brief, brisk plunges.
7-Day Water Temperature Forecast
Castletown Beach Monthly Water Temperature Averages
Historical monthly climatology. The warmest water in Castletown Beach occurs inJuly, August, September, October — peaking at15°C (59°F) in August.
Year-Round Water Temperature Curve (°C / °F)
Hover a bar for detailsFull 12-month data table — min / avg / max & swimming comfort
| Month | Min Water Temp | Average Water Temp | Max Water Temp | Swimming Comfort |
|---|---|---|---|---|
| January | 8°C | 9.3°C | 11.2°C | Very Cold (< 16°C) |
| February | 7.2°C | 8.3°C | 9.5°C | Very Cold (< 16°C) |
| March | 6.8°C | 8°C | 9°C | Very Cold (< 16°C) |
| April | 7.9°C | 8.7°C | 9.9°C | Very Cold (< 16°C) |
| May | 9°C | 10.3°C | 12.2°C | Very Cold (< 16°C) |
| June | 10.7°C | 12.2°C | 13.8°C | Very Cold (< 16°C) |
| July | 12.3°C | 13.9°C | 15.6°C | Very Cold (< 16°C) |
| August | 14.1°C | 15°C | 16.4°C | Very Cold (< 16°C) |
| SeptemberCurrent | 13.4°C | 14.9°C | 16.2°C | Very Cold (< 16°C) |
| October | 13.1°C | 14°C | 15.3°C | Very Cold (< 16°C) |
| November | 10.3°C | 12.3°C | 14°C | Very Cold (< 16°C) |
| December | 9.3°C | 10.5°C | 12.6°C | Very Cold (< 16°C) |
Swimming FAQs for Castletown Beach
Is the sea warm enough to swim in Castletown Beach today?
Typical sea surface temperature in Castletown Beach this time of year is 14.9°C (58.8°F) — classified as Very Cold (< 16°C). Wetsuit strongly recommended. Sudden entry may cause cold shock. Suitable only for brief, brisk plunges. Live readings load automatically.
What are the warmest months for swimming in Castletown Beach?
The highest water temperatures in Castletown Beach typically occur duringJuly, August, September, October, when monthly averages reach peak seasonal levels.
What is the typical water temperature in Castletown Beach in September?
Historically in September, water temperatures in Castletown Beach average around14.9°C (58.8°F), fluctuating between a recorded minimum of 13.4°C and a maximum of 16.2°C.