People are being urged not to travel, schools have closed and trains cancelled as temperature records are set to tumble in exceptionally hot and humid conditions.
Temperatures are expected to peak at around 37C on Wednesday and 38C on Thursday and Friday, the Met Office said, with a chance of even hotter spots, as a “heat-dome” settling over western Europe has brought extreme conditions across the continent.
In the UK, the previous June temperature record of 35.6C – set in the infamous summer of 1976 – could be smashed, as human-driven climate change fuels increasingly frequent and intense heatwaves.
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.
And the heatwave has prompted calls for the Government to take more action to protect the UK from increasingly extreme heat, including cooling for hospitals, schools and care homes.
Wednesday and Thursday’s red warning from the Met Office for extreme heat, which came into force on Wednesday morning in an area from London to Swansea and Somerset to Birmingham, has been extended to the south coast of England.
It now includes Brighton, Bognor Regis, Portsmouth, Southampton, Bournemouth and Dorchester, and runs until the end of Thursday.
The Met Office has also issued an amber warning for heat on Friday covering much of England.
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.
Temperatures will be a few degrees cooler than the previous days, but are still expected to exceed 30C widely in the area, which stretches from the Sussex coast to Lincolnshire, peaking around 32C to 34C in London or East Anglia, the weather service said.
A yellow warning for thunderstorms in south-west England has also been issued for Thursday evening.
Overnight into Wednesday, temperatures across many areas stayed above 20C, 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.
Met Office chief forecaster Matthew Lehnert said: “This is exceptional heat for June with temperature records expected to be broken this week.
“Red warnings are reserved for the most severe events and we’re expecting significant impacts from this heatwave, with health issues likely, even beyond those who are more vulnerable to the heat.
“High humidity is an additional factor for this heatwave which will mean the heat will feel much more potent for many.
“When you couple all of this with the high overnight temperatures, with temperatures likely to stay above 20C for large parts of England and Wales, these combined impacts all increase the potential for significant impacts.”
And 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.”
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 1am on Wednesday to 11pm on Thursday, and mean “adverse temperatures are likely to impact on the health and wellbeing of the population”.
More than 100 schools will be at least partly closed over the next days 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, adding: “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.
“Teachers are relaxing uniform rules, keeping classrooms cool, making sure children are hydrated, teaching critical skills like water safety, and avoiding vigorous activity on the hottest days. If your child has medical needs which mean you’re especially worried about the heat, talk to your school about what they can do.
“Every day of absence and lesson missed has a cost – and that cost falls hardest on our most disadvantaged pupils and working class communities. So, pack a water bottle, put on the sunscreen, and trust that your child’s school has got this.”
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.
Data from communication giant O2 showed travel to the West End was 13% lower today and down by 12% in the City, 11% in King’s Cross and 7% in Westminster.
National Rail warned of disruption to Gatwick Express, Great Northern, Southern and Thameslink services until Friday.
Avanti West Coast said it planned to run fewer services than usual between Tuesday and Thursday, and there is “a risk of further disruption”.
Chiltern Railways said it would extend the period when it is cancelling more than half its services into Friday, and advised customers to avoid travelling until the weekend.
Eurostar has had a “small” number of cancellations, and is running trains to Brussels at reduced speed for part of their journey, the operator said, as it advised vulnerable passengers to postpone their journey where possible.
The RAC said it had responded to 20% more callouts to broken-down vehicles than usual on Tuesday, and said Wednesday looked “even more challenging” with more cars succumbing to the heat.
Spokesman Simon Williams said: “We strongly urge people to avoid driving unless it’s essential, as breaking down in these conditions is potentially life-threatening if they aren’t properly prepared.”
NHS advice for how to cope during a heatwave includes keeping out of the heat when possible and cooling down with cold food and drinks, and closing windows and blinds during the day to keep the heat out of living spaces.
