Site emblem: two old-fashioned swimmers
Water temperatureEnter

United Kingdom: where to swim in May?

United Kingdom, in May: the sea is at 9.9 °C on average along the coast, from 8.7 °C to 11.7 °C depending on the spot. Where the water is warmest (11.7 °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

MonthAverage temperatureDepending on the spotWhere it is warmest
January8.8 °C7.5 °C – 10.2 °Ccold
February7.9 °C6.5 °C – 9.5 °Cvery cold
March7.9 °C6.5 °C – 9.4 °Cvery cold
April8.5 °C7.3 °C – 9.8 °Cvery cold
May9.9 °C8.7 °C – 11.7 °Ccold
June12.2 °C10.8 °C – 14.4 °Ccold
July14.1 °C12.3 °C – 16.6 °Ccool
August15.0 °C13.1 °C – 17.5 °Ccool
September14.3 °C12.5 °C – 16.9 °Ccool
October12.9 °C11.2 °C – 15.4 °Ccool
November11.5 °C10.3 °C – 13.5 °Ccold
December10.0 °C9.0 °C – 11.6 °Ccold

Compared with April, the water warms up by 1.4 °C in May. The warmest month: August (15.0 °C). The coldest: February (7.9 °C).

Nearby, in May

And right now?

For the temperature measured right now, station by station and to the hour: United Kingdom: water temperature

Frequently asked questions

What is the sea temperature in May?

United Kingdom, in May: 9.9 °C on average along the coast, from 8.7 °C in the coolest waters to 11.7 °C in the warmest (average of the years 2011 to 2025).

Can you swim in May?

Where the water is warmest (11.7 °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 (15.0 °C on average) and coldest in February (7.9 °C). Even where it is warmest, the water never reaches 20 °C in any month; the three warmest months are: August, September, July.

Where is the water warmest in May?

The warmest in May: Ireland (11.5 °C), Netherlands (10.6 °C), Denmark (10.1 °C). The coolest: Poland (9.1 °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.

← April · June → · Warmest water today