Cold. 9.0°C in April is cold-water swimming territory — a 4/3 mm full wetsuit, neoprene cap and short, repeated sessions are the safe approach.
Monthly averages set expectations, but the specific beach today depends on wind, swell and recent weather. Check the live value at the top of this page or open the Llanddwyn live page for full conditions.
Frequently asked questions
What is the average sea temperature at Llanddwyn in April?
Llanddwyn averages 9.0°C in April, based on long-run climatology for the Irish Sea.
Is the sea warm enough to swim at Llanddwyn in April?
Not without thermal protection — a wetsuit is recommended at 9.0°C.
Do I need a wetsuit at Llanddwyn in April?
A 4/3 mm full wetsuit, boots and neoprene cap are recommended.
