The heatwave's soaring temperatures are not so much to be enjoyed, as to be wary of, reports Correspondent Geraint Vincent
The UK is sweltering as its first red extreme heat warning came into effect on Monday.
Wales has already broken temperatures for its hottest day on record, while the mercury hit 38.1C in Suffolk's Santon Downham, making it the hottest day of the year.
Tuesday is predicted to be even hotter, with temperatures possibly reaching a 41C in Yorkshire and Lincolnshire.
The existing UK record, of 38.7C, recorded in Cambridge in 2019, looks certain to fall amid the sweltering heat.
The rise in temperatures has forced the UK Health Security Agency to issue a level 4 heat-health alert – described as an “emergency” – while the Met Office has issued the UK’s first red extreme heat warning, with both running from Monday to Wednesday.
People have been urged to take extra precautions during the heatwave, with the public urged against travelling unless essential, carrying water at all times and and keeping an eye out for the signs of heat exhaustion.
Extreme heat is dangerous, but for the vulnerable it can be deadly, reports Sejal Karia
Police also implored people to avoid cooling off in reservoirs, rivers or ponds after 13-year-old in Northumbria, a 16-year-old in Maidenhead and a 16-year-old in Greater Manchester drowned while open water swimming.
The body of a 50-year-old man was recovered from Ardsley Reservoir, between Leeds and Wakefield, on Sunday.
Mel Bloor reports after a 16-year-old boy was found dead after drowning in a Maidenhead lake
Drivers have been urged to travel during cooler parts of the day, while passengers have been told to check their train service is running ahead of travel as dozens of rail operators have cancelled services or warned of delays.
Luton Airport reportedly had to divert flights after soaring temperatures melted the surface of its runway. Flying activity was also halted at RAF Brize Norton amid the heatwave.
Twelve fire appliances had to rush to a large wildfire at Lickey Hills Country Park on the outskirts of Birmingham after a blaze ravaged around 400 square meters of green space.
It comes after experts warned that wildfires could tear through the countryside as temperatures threaten to soar to highs of 40C.
ITV News Northern Reporter Sangita Lal reports on the disruption the heat will have tomorrow in Yorkshire and Lincolnshire, two regions where temperatures could reach 41C
Chief meteorologist at the Met Office Paul Davies warned Monday night will be “very oppressive” and it will be "difficult" to sleep in the heat.
The top forecaster said he was “really concerned” about the UK hitting 40 or 41C on Tuesday.
Meanwhile, Met Office climate attribution scientist Dr Nikos Christidis said the 40s prediction is a result of climate change.
People have been urged to avoid being wasteful with water - particularly in their back gardens.
Social Affairs Correspondent Sarah Corker reports on how people are keeping cool in the heat
The water demand reduction manager for Thames Water Andrew Tucker told customers to be careful with water usage as the heatwave has led to demand being “at near record level”.
Mr Tucker told BBC Radio 4 that Thames Water is not currently considering any water restrictions, but that could change if there is little rainfall in the coming months.
“Our call is basically ‘stay hydrated, look after your health, but please use water very very carefully and don’t waste it’," he added.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know
Ministers held a virtual emergency Cobra meeting on Saturday to put a contingency plan in place for the country after meteorologists warned the record high temperatures could put lives at risk.
Boris Johnson faced criticism for not attending the meeting and instead spending the weekend having a party at Chequers.
Labour frontbencher Lisa Nandy accused the outgoing PM and his ministers of having “clocked off” during the UK’s first red extreme heat warning.
Defending Mr Johnson, Cabinet Office Minister Kit Malthouse told Sky News: “It’s my job to chair Cobra meetings. I briefed him yesterday morning at about 8am personally.”
As the broadcaster showed aerial footage of Mr Johnson with his guests at Chequers, Mr Malthouse said it was “completely unfair” to suggest that the PM was ducking important meetings because he would be leaving the job soon.
Following the Cobra meeting, Health Secretary Steve Barclay said the emergency services were already starting to see an increased volume of calls, but Tuesday afternoon was the “point of maximum concern” as the highest expected point of the heatwave.
Additional contingency support has been put in place for ambulance services, such as more call handlers and extra working hours.
On Monday, Downing Street said the NHS is “coping well” with the extreme heat, and no deaths have been reported centrally at this stage.
However, Milton Keynes University Hospital has cancelled routine outpatient appointments and surgery on Monday and Tuesday, while Lord Victor Adebowale, the chairman of the NHS Confederation, told Times Radio that hospitals will be “really, really pushed” over the next few days.
Schools in several counties, including Nottinghamshire and Hampshire, confirmed they will not be open on Monday and Tuesday following the health warnings.