An ongoing heatwave in Britain, which has pushed temperatures above 30C, was 10 times more likely because of climate change, according to research released as an amber health warning was issued across England.
Temperatures are forecast to reach up to 34C on Saturday after hitting 32.2C at Kew Gardens in London on Thursday afternoon, making it the hottest day of the year in the UK.
Parts of the country could experience the first tropical night of 2025 over the weekend, when the temperature remains at or above 20C for 24 hours.
Scientists at the World Weather Attribution, an academic group that analyses weather events, said climate change had made a 32C day in the UK 100 times more likely than in the pre-industrial era. A June heatwave of three consecutive days above 28C was 10 times more likely to occur now.
“With every fraction of a degree of warming, the UK will experience hotter, more dangerous heatwaves,” said Ben Clarke, researcher at the Centre for Environmental Policy at Imperial College London. “That means more heat deaths, more pressure on the NHS, more transport disruptions, tougher work conditions and poorer air quality.”
The Met Office, the UK’s national weather service, this week said the country had a 50-50 chance of a 40C day in the next 12 years, after that threshold was broken for the first time in 2022.
Drought
The hot weather follows the driest spring in more than a century, which has left large parts of the UK battling drought.
Companies, including Yorkshire Water, United Utilities, Affinity Water and Welsh Water were asking customers to voluntarily curb consumption, which has increased this year.
No hosepipe bans are in place but the Environment Agency has declared a drought in the north-west and Yorkshire, while warning of extreme low rainfall in other areas.
Water UK, the industry trade body, was urging people to save water after a poll found people in England and Wales believed their household used just 62 litres of water a day — roughly the amount used in a five-minute shower — when in reality, the average household used 323 litres a day.
“Over the next five years water companies will start work on nine new reservoirs as part of their record £104bn investment to secure our water supplies, help build more homes and support economic growth,” it added.
Heat deaths
The UK’s older housing stock, which often retain summer heat, as well as a lack of air-conditioning in homes means Britons are more exposed to heat than in some other parts of the western world.
On Thursday, the Health Security Agency and Met Office issued a rare amber health weather warning, used to indicate that weather impacts are likely to be felt across the whole health service, with older people and those with health conditions most at risk.
About 2,000 people in the UK died during a heatwave in 2003, while there was about 3,000 heat-related deaths in the summer of 2023, when a severe heatwave hit Europe.
Akshay Deoras, a scientist at the University of Reading, said heat-related deaths were “preventable tragedies that disproportionately affect our most vulnerable citizens”, including elderly people, young children, those with chronic health conditions, and people experiencing homelessness.
“The human body struggles to cope when temperatures soar, leading to dehydration, heat exhaustion, and potentially fatal heatstroke,” he added.
The London Mayor’s office has been working with local councils to provide emergency support to the city’s homeless population during the heatwave.
Those working outside are also exposed to heat-related health risks. On Monday, the Trades Union Congress urged the UK government to institute a maximum working temperature, similar to laws in Spain, Germany and China.
Solar power
Britain’s solar power output was at a record high, with total generation up almost 40 per cent this year compared with the same period in 2024. More than 10 per cent of total electricity generation came from solar in April and May, according to an analysis by climate news website Carbon Brief.
At midday on Thursday as much as one-third of Britain’s electricity demand was being met by solar, according to University of Sheffield data.
The surge was due to the sunny weather and increased installed capacity of photovoltaic panels. As of April there was more than 18 gigawatts of capacity, 1GW of which was added in the past year, official figures show. The government aims to hit 45-47GW of capacity by 2030.
Leisure
The sunny spell has also led to an increase in leisure activity and spending as Britons emerged blinking into the sunshine.
Tesco, JD Wetherspoon, Next and Kingfisher, which owns DIY chain B&Q, have all attributed sales boosts this spring to good weather. The chief executive of bakery chain Greggs, Roisin Currie, told the Financial Times last month the warm weather had got people “out and about more”.
Train bookings to the 12 most popular seaside towns around the UK were up by a quarter on average this week, according to Trainline data. Meanwhile, cycle journeys on London’s Victoria Embankment — a vital thoroughfare for the capital’s bike commuters — exceeded 18,000 on Monday, a record for a day without a Tube strike, according to a crowdsourced social media account monitoring Transport for London counters.
Climate Capital
Where climate change meets business, markets and politics. Explore the FT’s coverage here.
Are you curious about the FT’s environmental sustainability commitments? Find out more about our science-based targets here
