The record for the UK’s hottest June day has been broken for the third time on Wednesday, with a provisional temperature of 36C breaking the previous record from the summer of 1976.
The record was broken when provisional temperatures reached 36C in Wisley, Surrey, and Gosport, Hampshire, the Met Office said.
It follows provisional temperatures reaching 35.7C in Charlwood, Surrey, and 35.8C at Wiggonholt, West Sussex, earlier on in the day.
Wednesday’s highs break the previous top temperature of 35.6C in 1976 and 1957, the forecaster said.
It comes as much of England and Wales swelters in exceptionally hot and humid conditions, which have prompted a rare red warning from the Met Office for extreme heat.
The heatwave, which has led to health warnings, school closures and transport disruption, is driven by a “heat-dome” settling over western Europe that has brought extreme conditions across the continent.
The 50-year-old record has fallen as climate change, mostly the result of burning fossil fuels, is driving increasingly frequent and intense heatwaves, which experts say the UK is not prepared for.
Figures are currently provisional and would be verified at the end of the heatwave to check if it is a new national record.
Met Office science manager Amy Doherty said: “If confirmed, a new June daily temperature record would be significant, especially following on the heels of the recent records set in May.
“The new record provides further evidence that temperatures previously considered extreme are becoming increasingly common as a result of human-induced climate change.”
Temperatures could rise even higher on Thursday, the Met Office said.
If they hit 39C, that would make it the second hottest day in the UK on record and the hottest June day on record. If 38C is recorded, that is still in the top five days ever recorded and still hotter than any day of the 20th century.
The record comes amid a sweltering heatwave, with the Met Office issuing a rare red warning for extreme heat for Wednesday and Thursday for an area from London and the south coast to Swansea, Somerset and Birmingham.
Red heat health alerts have also been issued by the UK Health Security Agency (UKHSA) for the East of England, East Midlands, London, the South East, the South West and the West Midlands, and amber heat health alerts for the North East, North West, and Yorkshire and The Humber.
These alerts are in place from 4pm on Wednesday to 11pm on Friday, and mean “adverse temperatures are likely to impact on the health and wellbeing of the population”.
The Met Office has also issued an amber warning for heat on Friday covering much of England, while a yellow warning for thunderstorms is in place for the South West on Thursday evening.
And with the extreme heat set to linger in some parts of the country into the weekend, the Met Office has issued an amber warning for extreme heat covering parts of east and south-east England on Saturday.
At least 1,000 schools and nurseries will either be closed or partially closed in England and Wales over the next two days.
Some have brought in early finishing times or relaxed uniform rules, while transport services have been disrupted and people are being urged to stay inside, close windows and curtains and stay hydrated to beat the heat.
Night time temperatures have also been unusually high, staying above 20C in many places, with Brize Norton in Oxfordshire not dipping below 22.3C and Heathrow, west London, not dipping below 22.1C, the Met Office said.
These “tropical nights” make it hard to sleep and for people to recover from the heat of the day, experts warned.
More than 100 schools will be at least partly closed in Bristol, Gloucestershire, Oxfordshire, Buckinghamshire and Hampshire. In Somerset, more than 200 schools will be shut or operating on more limited opening hours.
Children at some schools have been told they can wear PE kit rather than full school uniform, which can involve long trousers and blazers.
Education Secretary Bridget Phillipson has said parents should send children to school if they remain open, saying schools were taking steps to help pupils cope with the heat, and absences had a cost.
“I know hot weather can be a struggle. But my message to families is simple: if your child’s school is open, you should keep sending them into school,” she said.
Transport bosses have urged people to avoid travelling on Wednesday and Thursday and are warning those that do to “prepare for a disrupted journey”.
Travel into central London in the past few days was down on last week as workers heeded advice to stay at home during the heatwave, while there were disruptions on a raft of rail lines.
The heatwave has prompted new calls for the Government to take more action to protect the UK from increasingly extreme heat – a feature of the changing climate – including cooling for hospitals, schools and care homes.
The Met Office said the frequency and intensity of heatwaves has increased worldwide.
Professor Stephen Belcher, Met Office chief scientist, said: “Human induced climate change has made events like this more likely and more intense.
“To see temperatures like this in the UK in June is sobering.
“Events like this bring home the implications of climate change, with very high temperatures and humidity bringing significant health implications from heat stress, as well as impacts to a range of sectors such as transport, energy and water supply.”
In Hampshire, Testwood Lakes, near Totton, Southampton, has been closed off to the public as police marine units join other emergency services in the search for a 15-year-old boy who was reported missing after last being seen swimming at 1.35pm on Wednesday.
Police marine units have joined emergency services in the search for a 15-year-old boy who was reported missing at 1.35pm on Wednesday after last being seen swimming at Testwood Lakes, near Totton, Southampton.
A Hampshire Constabulary spokesman said: “We have deployed the marine units to aid in the search, alongside colleagues from NPAS, South Central Ambulance Service, and Hampshire & Isle of Wight Fire Service.”
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