The United Kingdom experienced its hottest June day on record Thursday, with a provisional temperature of 36.4C (97.5F) measured in Yeovilton, Somerset, according to the Met Office. This surpasses Wednesday's record of 36.1C in Gosport, Hampshire, and the previous peak of 35.6C set in Southampton in 1976. The brutally hot conditions, supercharged by the climate crisis, continue to envelop Europe.
Earlier Thursday, Cardiff broke another UK heat record with a minimum temperature of 23.5C overnight, the highest June minimum temperature ever recorded. Heatwaves are now more severe and likely due to carbon pollution from burning fossil fuels, with scientists estimating current extreme temperatures across Europe are 2C to 4C higher as a result.
Health and Infrastructure Under Strain
The UK Health Security Agency (UKHSA) extended its red heat-health alert by 24 hours to 11pm on Friday, only the second red alert ever issued. The Met Office also extended its red alert for south-east England until 9pm on Friday. Many thousands are likely to have died prematurely in the heat, though statistical analysis takes time. The UKHSA found that more than 10,000 people died in Britain due to summer heatwaves between 2020 and 2024. Globally, rising heat is now killing one person a minute, health experts said in October.
Simon Stiell, the UN's climate chief, stated: "Europe's savage heatwave is the latest price to pay for fossil fuel pollution baking our planet. Schools closing, the vulnerable dying, economies sweating: this is what the climate crisis looks like in practice, and it's just getting started." He added: "Extreme heat will keep getting worse, and other climate impacts – from mega-droughts, floods, wildfires and storms – will keep hammering every economy and population harder each year. But the solutions are equally clear: a faster shift to renewables – which are now much cheaper than fossil fuels – as well as protecting forests. There's no time to lose."
Government and City Responses
The UK parliament voted overwhelmingly on Wednesday to set a legally binding target of an 87% cut in emissions by 2040, as proposed by the Climate Change Committee. The committee said in May that the UK's infrastructure was "built for a climate that no longer exists" and needed urgent improvement. Many schools have closed and rail journeys have been cancelled during the heatwave, exacerbated by high humidity.
Sadiq Khan, the mayor of London, launched the city's first heat plan on Thursday. "Extreme temperatures are no longer a future threat, they are a present danger," he said. The plan includes retrofitting homes at highest risk of overheating, more tree cover, and safe access to water for paddling and swimming. A 2025 study found the number of UK homes reporting overheating in summer quadrupled to 80% in a decade.
Surface Temperatures Soar
Measurements by Greenpeace found pavements, rail platforms, building sites and other places across London reached surface temperatures of 50C to 60C on Wednesday. The black rubber floor of a playground in Islington was recorded at 53C at 5pm. Mel Evans, Greenpeace UK's head of climate, said: "This record-smashing heatwave has turned London into a sticky, sizzling cauldron. This isn't just weather – it's a public health emergency driven by fossil fuel giants. These abnormal temperatures are stretching homes, schools, transport and our own health to breaking point."
