The Met Office has revealed the exact time the current UK heatwave will end as it issued an update amid extreme temperatures across the country.

Britons are set to melt on the hottest UK day on record as temperatures are predicted to hit 40C amid growing travel chaos.

The mercury will sizzle at possible highs of 41C in isolated areas on Tuesday, making the country hotter than Jamaica, the Maldives and Barbados – with rail users warned of delays, cancellations and changes to train services.

However, the Met Office has said tonight will be a lot cooler as the temperature drops to below 20C by midnight, meaning sleepless nights won’t last much longer.

Temperatures will remain in the mid-20s until around 11pm before the mercury drops overnight.

Throughout the rest of the week, temperatures should become milder with it predicted to be “cloudier and much less hot on Wednesday”.

The Met Office’s chief meteorologist Paul Davies said: “I’ve been doing this job for about 30 years and I’ve never seen the type of charts I’ve seen. The speed at which we are seeing this exceptionally high temperature is broadly in line with what we are saying, but the brutality of the heat is astounding.

“It could become a regular occurrence by the end of the century.”

Met Office weather forecast

A Met Office weather forecast reads: "An exceptionally hot and sunny day with record breaking temperatures. Some cloud building at times, and a few showers are expected later in the afternoon.

"A bright end to the evening with high temperatures persisting into the first half of the night, cloud gradually pushing in from the west as fresher conditions arrive."