Interactive map reveals the 24 beaches you must avoid this summer – is your favourite bathing spot on the list?

AS temperatures soar and Brits bask in the sunshine, many will be dreaming of cooling off at the beach.

The mercury is expected to hit a glorious 31C tomorrow – after many soaked in 28C rays today.

And while the masses will be racing to the beach for a dip to cool off, a warning has gone out about the quality of water at some popular swimming spots.

Surfers Against Sewage, a marine conservation charity, has revealed beaches and rivers to avoid this summer.

The reasons range from sewerage discharge to general health hazards.

In Cornwall, Harlyn Bay has an alert due to a sewer overflow, with Porthluney given a poor classification and advised against bathing completely.

Brighton Beach is clear, but down the road at Seaford is a no-go.

The popular sands of Whitby are also on alert, along with Ballyholme in Northern Ireland.

It comes after four heat alerts were scattered in certain locations from today, as temperatures are expected to soar tomorrow.

The Met Office says there’s a chance the mercury will hit 31C in London on Friday, with the likes of Norwich, Birmingham and Hull expected to enjoy temperatures just a couple of degrees lower.

But, in a reminder to Brits to still take care in the summer conditions, the UK Health Security Agency (UKHSA) has placed yellow heat alerts in four locations.

East Midlands, East England, London and the South East have been warned to take from today at 5pm – with the alert in place until 11pm on Saturday.

Its warning says the heat could impact vulnerable people as they could become increasingly warm while inside, and there were chances the need for healthcare services could rise.

The Met Office said the temperatures would start soaring to a high of 28C today.

Forecasters said that tomorrow would be warmer though – to the delight of Brits.

Meteorologist Annie Shuttleworth said: “In the peak of the heat we could see 28C on Thursday, that’s probably the highest temperature we’ll see on Thursday, but widely across England and Wales will be in the mi- 20s, 25C is quite likely even across southern areas of Wales.”

A map showed London was expected to hit 28C.

Giving tomorrow’s forecast, Annie said: “Apart from the fact that we will start to see that heat build even further with strong sunshine expected widely across England and Wales – very high UV levels as well.”

She said there was a chance of “30C, potentially 31C is possible for the greater London area”.

Annie added: “Quite widely will be in those high 20s across many central and south eastern areas of England as well.”

A map showed that Norwich and Birmingham would likely hit 28C, Hull 27C, Southampton 26C and Manchester 25C.