Britain 'hotter than Mumbai and Madrid'

The highest recorded was at Heathrow Airport where the temperature reached 83F (28.4C).

It meant Britain was hotter than Istanbul (28C), Mumbai (27C), Madrid (26C) and Rio de Janeiro (23C).

An estimated 50,000 people headed for Dorset beaches to enjoy the warm sunshine.

Millions have already taken advantage by snapping up deckchairs at seaside resorts such as Bournemouth.

However, the highs still have some way to go to top the hottest day of the year so far in Britain which was 33.1C on 27 June in Gravesend, Essex.

Temperatures reached 77F (25C) over the weekend and are expected to reach a sweltering 86F (30C) by Wednesday.

But thunderstorms are expected by the middle of the week and forecasters cannot be sure when the next heatwave will come.

Andy Bodenham of the Met Office said: “In the next few days the conditions are likely to set off thunderstorms just about anywhere in the country.

“That will herald low temperatures for most parts. People should make the most of the weather while they can.”

Sarah Holland, spokesman for the Met Office, said high pressure from the Mediterranean had arrived over the UK, causing the rise in temperatures.

She said: "We are seeing some warm temperatures now but they are quite common for August. It probably just feels a bit hotter because of some of the cold days we had in July.

"We have got high pressure that has come from the continent.

"It will be a little cooler on Tuesday in Bournemouth with temperatures of 22C but they should rise again to about 28C in parts of the south east on Wednesday.

"We can also expect some showers this week, especially at night."

Charles Baker, 36, from Hordle, Hampshire, was one of the throng visiting Bournemouth this weekend with his partner Aileen Simpson and one-year-old daughter Alice.

He said: “It’s glorious today. The beach is really busy and I expect people have come because they don’t know if the warm weather will last.” telegraph