A new weather warning for "extreme heat" has been issued by the Met Office - with UK temperatures set to reach as high as 38C next week.
The amber warnings now cover parts of England and Wales over four days next week - as much of Europe swelters in blistering heat.
The first amber warning for Monday and Tuesday covers central and southern England and parts of Wales.
A second amber warning has now been issued for Wednesday and Thursday, covering similar areas as well as parts of northwest England and North Wales.
See the weather forecast where you are
The Met Office said temperatures are expected to reach 38C in London on Wednesday and Thursday.
Forecasters have "growing confidence" this week could break the record for the hottest June temperature of 35.6C set in Southampton in 1976.
Met Office meteorologist Jonathan Vautrey said: "It's particularly across central southern regions, where we have an extreme heat warning, an amber extreme heat warning issued, where we could see quite widely amongst the population some heat-related impacts throughout the week.
"Temperatures climbing towards the mid-30s in places, that is quite exceptional for June."
Elsewhere in Europe, an ongoing heatwave has triggered weather warnings.
French authorities have put into place public alcohol restrictions and have cancelled some outdoor sporting events.
Highs of 40C are expected there on Sunday with Monday due to be even hotter. Emergency services and military forces have been put on wildfire alert.
In Spain, the first heatwave of the year was declared by officials as temperatures reached up to 40C in the capital Madrid.
Aemet, the state-run weather forecaster, said 13 of the country's 17 regions were under "orange" alerts for heat on Sunday, meaning residents were being advised to take precautions amid the severe conditions. Meanwhile, the Basque Country, in Spain's northwest, was on red alert, the highest level of weather warning.
Read more:
Jeremy Clarkson reveals 'aggressive' cancer is in remission
Swimmers brave water after woman mauled by shark
A public outdoor screening in central Madrid of Spain's World Cup match against Saudi Arabia this evening has been cancelled because of concerns about the heat, The Guardian reported.
Temperatures of 37C are also forecast in Rome on Monday.
(c) Sky News 2026: UK weather: Four-day extreme heat warning issued - as temperatures set to hit 38C
Driver who died in Bedford train crash that left 100 people injured is named
Girl and two boys arrested on suspicion of murdering teenager - as victim named
England cricketers Stokes and Atkinson 'not to blame for violent conduct' during nightclub incident
Prince William's children call him 'best papa' on 44th birthday
Police name teenage spectator killed after crash at Donegal International Rally
Ocado shops for successor to co-founder Steiner | Mark Kleinman blog
Murder investigation after man stabbed to death in southeast London
'Vandals arrested' as Trump's $14m reflective pool project sees it turn green again