Extreme heat warnings have been extended as parts of England and Wales swelter in exceptionally hot and humid conditions.
Temperatures could hit 40C on Wednesday and Thursday in some spots as a “heat-dome” settling over western Europe has brought extreme conditions across the continent.
In the UK, the previous June temperature record – set in the infamous summer of 1976 – could be smashed by several degrees celsius, as climate change fuels increasingly frequent and intense heatwaves.
Schools have closed, 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.
Wednesday and Thursday’s red warning from the Met Office for extreme heat in an area from London to Swansea and Somerset to Birmingham, with temperatures potentially climbing as high as 40C, 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, with the hottest spots potentially peaking around 38C in eastern and central areas.
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.
During the peak of the heatwave on Wednesday, the temperature could come close to the UK’s all-time high of 40.3C, which was measured in Lincolnshire in July 2022, when a red warning for heat was issued for the first time by the Met Office.
The latest heatwave is also expected to surpass the record for June of 35.6C set in Hampshire in 1976.
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.
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”.
The combination of extreme heat and humidity could also have impacts on infrastructure, power and water supplies, the Met Office said, and could cause heat-related issues for a range of sectors such as transport, energy and water supply.
There could also be an increase in water safety incidents during the heatwave, the agency said, as more people are likely to visit coastal areas, lakes or rivers.
Almost 100 schools in Somerset will be fully closed on both days, according to Somerset Council.
About 100 will be at least partially closed in Buckinghamshire, along with 86 schools in Gloucestershire, according to council data.
Children at some schools have been told they can wear PE kit rather than full school uniform, which can involve long trousers and blazers.
Transport bosses have urged people to avoid travelling on Wednesday and Thursday and are warning those that do to “prepare for a disrupted journey”.
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 had axed more than half its services until Friday “to ensure the safe operation of the railway”.
Eurostar has cancelled four trains planned to run between London and Paris on Wednesday and Thursday “due to expected adverse weather”.
The AA said its overall workload was up 6% above planned levels on Tuesday, “reflecting increased demand”.
The London Fire Brigade has advised people in the capital to keep safe in the heat over the next few days, and be careful with the risk of wildfires and water incidents.
NHS trusts across England, including Moorfields Eye Hospital NHS Foundation Trust and Barts Health NHS Trust, have advised people attending appointments during the heatwave to make sure they bring water and check travel beforehand.
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.
The Liberal Democrats have called for the Government to immediately open air-conditioned public buildings as “cool hubs” for vulnerable people during the heatwave.
The party also urged ministers to urgently prepare the country for more extreme temperatures by investing in cooling for hospitals, care homes and schools – echoing a call by the independent advisory Climate Change Committee on helping the UK adapt to global warming.
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.
