Glorious sunshine and soaring temperatures will have Brits flocking to beaches and parks this weekend.
But with the Met Office issuing a “danger to life”warning over the blistering weather, NHS staff fear being overwhelmed by a huge surge of heat-related casualties.
And as temperatures could hit a record 40C – normally seen at the world’s hottest place, Death Valley in California – experts warn of a climate catastrophe that could kill hundreds of Brits.
With hospitals already struggling after a decade of cuts, one doctor said a heatwave is the “last thing the NHS needs”.
Cardiff A&E consultant Dr Farbod Babolhavaeji, 38, added: “I think people are very worried about it because we are already under extreme pressure.
“This extreme weather is going to cause a lot of problems because we are not used to it in this country.
“I don’t think people appreciate how hot it can get and we just have to be very careful. People should hear the basic advice again… keep out of the hot part of the day, stay indoors, stay in the shade, make sure they are drinking plenty.
“It’s not just the sun stroke and heat exhaustion and collapses. There’s a significant risk of developing a stroke in the heat.
“There are long waits for ambulances outside A&Es and despite everything we are doing the increasing demand means we are struggling to find space for the patients.”
New figures show ambulance response times have got worse, with an average wait of 51 minutes and 38 seconds for emergency calls such as heart attacks and strokes. That is well above the target of 18 minutes.
As the Government today held a Cobra on the heatwave, climate change senior lecturer John Grant urged No10 to act fast.
He said: “I think hundreds are going to die in the UK if not thousands, that’s my fear if we hit temperatures of 40C.
“It’s terrifying what will happen if we don’t have a management plan and get cooling centres ready.”
Former Environment Agency boss Dave Throup warned forecast models seem to be “firming up on some incredible temperatures”.
He added: “If they materialise it will be unprecedented in the UK, It will also be incredibly dangerous.”
Cabinet Office minister Kit Malthouse urged the public to look out for vulnerable neighbours.
He said: “People need to do all the stuff they would do when it is very hot, wear a hat, drink water.
“But it’s critical, with the elderly, those with cardiovascular problems and the very young, that people look out for them and take care.”
Temperatures will hit 30C on Saturday and could peak at 35C next week. But Mr Malthouse added: “There is a possibility we could hit 40 which would be an all time record.”
Events have been cancelled all over the UK including school sports days.
Despite the fears, Brits are still cramming onto beaches, with some arriving at the crack of dawn.
Emile Crosby, 24, who runs the Natural Surf School in East Wittering, West Sussex, said: “There’s families getting down to the beach at 6.30am to 7am to get a space.”
And ice creams sales are expected to hit a record high of nine million this weekend, Tesco said.
Barbecue burgers and sausages, beer, wine and salads will also fly off the shelves.
But the heat could spark travel chaos as millions take to trains, planes and cars to get away. A burst water main today at Gatwick Airport left restaurants and toilets closed.