Monday could be the warmest day of the year so far with temperatures reaching as high as 35C on what is expected to be another day of sunny weather for much of the country.
High pressure winds drawing in warm air from Europe caused temperatures to climb on Sunday and remain high on Monday but they are expected to return to average levels on Tuesday, the Met Office said.
Severe thunderstorm warnings have also been issued for parts of the UK, including Scotland and Northern Ireland.
Temperatures are unlikely to exceed the 40.3C recorded at Coningsby, Lincolnshire, on July 19 2022, the highest temperature ever recorded in the UK, according to forecasters.
But the heat will be so intense that it will feel ‘quite uncomfortable’ in central eastern England, Met Office forecaster Craig Snell said.
He added: ‘It’s going to be hot. The weather is coming with a lot of humidity, so it will feel quite uncomfortable out there across central eastern England.
Beachgoers splash in the waves at Bournemouth. Britain could experience its hottest day of the year yet on Monday with temperatures set to soar to a peak of 35C
People enjoy the hot weather on the beach at Watergate Bay, Cornwall during the Boardmasters festival
Sunbathers fill Margate beach amid scorching summer heat on Sunday
‘Elsewhere, it’s still going to be warm and humid, but the hottest weather will be in central eastern England.’
The Met Office recommends that people keep curtains closed during the peak of the day and drink lots of water.
London, East Anglia and the home counties will experience the warmest weather, with highs of 33C expected in London, 26C in Manchester and 21C in Edinburgh.
Thunderstorms are expected in Northern Ireland, Scotland and northern England on Sunday night and early Monday morning, leading to torrential downpours in some areas.
The Met Office has issued a yellow weather warning for the affected regions over the next 24 hours, telling drivers to expect spray on the roads and some road closures.
Mr Snell said: ‘Thunderstorms are already beginning to move into the Republic of Ireland.
The Met Office has issued a yellow warning for thunderstorms for Scotland and Northern Ireland over the next 24 hours
People enjoy punt tours along the River Cam in Cambridge on Sunday
Boaters hold sun umbrellas to shelter from the intense heat while enjoying a ride on the River Cam in Cambridge
Sunbathers take in the hot sunshine on the beach in Weymouth, Dorset
‘They will start to move up into Northern Ireland later this evening and then move across Scotland and northern England as we go through the night and into tomorrow.
‘It could be potentially quite nasty in places up there.’
He added: ‘Although we probably won’t see that severe weather across the south, that system will gradually bring some cooler temperatures to all parts as we go through Tuesday and Wednesday, with highs back up to the high 20s rather than mid 30s.’
The hottest day of 2024 so far was Friday July 19, where temperatures reached a sweltering 31.9C in central London.
