
Heatwaves like the one set to affect the United Kingdom this weekend are now ten times more likely to occur compared to the cooler pre-industrial climate.
—
June days where temperatures exceed 32C in southeast England are significantly more likely to occur because of human-induced climate change, a new study has warned ahead of an early-season heatwave in the UK.
The World Weather Attribution (WWA) group found that there is a 100-times higher likelihood of having June days with temperatures above 32C in today’s climate, which is 1.3C warmer than pre-industrial times. It comes as temperatures are supposed to sore past 32C in parts of the UK this Saturday.
A heatwave is expected to affect much of the UK throughout the weekend, after heat built up through the week, the Met Office said on Thursday. Temperatures on Saturday are forecast to exceed 30C in much of the country, with highs of 34C in eastern England, the UK’s weather service added. For heatwave conditions to be met, temperatures need to reach 25C across the north and west of the country, and 28C in parts of southeast England for at least three consecutive days.
The likelihood of crossing southeast England’s heatwave threshold in June has increased from about once every 50 years in cooler pre-industrial climate to about once every five years in today’s climate, the study also found. In other words, every June there is now a 20% chance that the region will experience a heatwave.

Heatwaves kill nearly half a million people each year globally, making them the deadliest extreme weather event. Like other extreme weather events such as floods and droughts, heatwaves have been made more frequent and intense by climate change, which is primarily a consequence of fossil fuel burning.
Heat is extremely dangerous for humans as it compromises physiological processes meant to keep the body cool, heightening the risk of heatstroke and other heat-related illnesses. It can be life-threatening if not promptly treated.
Early-season heatwaves like this one tend to be deadlier as people are not yet acclimatized to summer temperatures, the study warned. People over 65 and those with pre-existing conditions such as respiratory and cardiovascular disease are more vulnerable and face a heightened risk of death.

‘Lagging Behind’
Heatwaves are expected to increase in frequency and intensity in the UK, according to a new Met Office study underscoring the “need to prepare and plan for the impacts of rising temperatures now.”
Yet the country is still “lagging behind” on adaptation and heatwaves remain an “overlooked threat”, WWA researchers warned. An update to building regulations in England now requires construction companies to take extreme heat into consideration – yet most existing homes remain highly vulnerable to overheating in the summer months, they said.
“It is totally insane we have political leaders in the UK trying to drag us back to the past with calls for more fossil fuels,” said Friederike Otto, WWA’s Co-Founder and Associate Professor in Climate Science at the Centre for Environmental Policy at Imperial College London. “The climate will continue to drive increasingly dangerous heatwaves, fires and floods in the UK until emissions are reduced to net zero globally.”
The UK High Court of Justice last year ruled that the country’s net-zero strategy – The Carbon Budget Delivery Plan – was in breach of the law, after handing down a similar verdict in 2022.
The court found the original plan inadequate because it lacked sufficient information on how the government would meet its emissions reduction targets and relied on potentially unproven technologies.
It initially instructed the government to draw up a revised plan within 12 months, though it eventually granted an extension, with the new deadline set for October 2025.
Featured image: Alisdare Hickson/Flickr.
Check out our 3-part series on extreme heat
💡How to stay safe in extreme heat
- 💧Stay hydrated: Drink around two liters of water per day, or about eight glasses. In heat conditions, experts recommend drinking throughout the day and urinating around six to seven times a day, or every two to three hours.
- 🍉Eat nutritious food: Stick to hydrating, fresh food such as watermelon, peaches, berries, grapes, and oranges, vegetables that can be juiced, as well as liquid meals such as soups. Avoid spicy foods, known to make the body sweat. Avoid cooking at home, and opt for the microwave instead of the oven if you have to.
- 💦Exercise responsibly: If you exercise outdoors, take breaks in the shade or indoors to allow your body to cool down faster. Wear sensible attire, such as lightweight, loose-fitting clothing made of breathable fabrics, such as cotton, linen, bamboo, polyester, nylon and microfiber. Hydrate well before a workout and drinking throughout every 15-20 minutes, especially when the physical activity lasts longer than an hour.
- 🌡️Follow local weather services: Check local meteorological services or news channels regularly, as they provide real-time updates and alerts about heat advisories and warnings. Local governments and emergency management agencies often post timely updates on social media platforms as well so keep them monitored.
- 📱Use weather apps: Download reputable weather apps that provide notifications about extreme heat conditions. Many of these apps allow users to set alerts for specific weather events in their area.
- ❗Sign up for emergency alerts: Many cities have rolled out local emergency notification systems or community alert programs that citizens can easily enroll in. These services often send text or email alerts directly to residents during extreme weather events, including heatwaves.
For more tips, check out our article on this topic. To learn more about the risks of extreme heat and how the world is adapting, you can read our 3-part series on extreme heat.
This story is funded by readers like you
Our non-profit newsroom provides climate coverage free of charge and advertising. Your one-off or monthly donations play a crucial role in supporting our operations, expanding our reach, and maintaining our editorial independence.
About EO | Mission Statement | Impact & Reach | Write for us