More than 2,700 excess deaths occurred in England and Wales during heatwaves that lasted through May and June 2026 [1].
These findings highlight the growing vulnerability of the UK population to extreme temperature events as global warming intensifies. The scale of the mortality suggests that current public health infrastructure may be insufficient to protect citizens during prolonged heat periods.
The estimates were published Monday by researchers from Imperial College London, the UK Met Office, and the London School of Hygiene & Tropical Medicine [1]. The study analyzed mortality data from the two-month period to determine how many additional deaths occurred beyond the expected baseline for those months [8].
Climate change played a significant role in the severity of the weather. Researchers said that temperature increases of about three to four degrees Celsius driven by climate change made the heatwaves more intense [6]. This shift in temperature is estimated to have accounted for roughly 42% of the excess deaths [4].
While the 2,700 figure is an early estimate, it reflects a pattern of increasing heat-related mortality across Europe. The researchers said that the combination of higher baseline temperatures and extreme spikes creates a compounding effect on public health.
Public health officials have previously warned that the UK is less prepared for extreme heat than nations in Southern Europe. The data from this year's heatwaves provides a concrete measure of the risk associated with the region's changing climate profile.
“More than 2,700 excess deaths occurred in England and Wales during heatwaves that lasted through May and June 2026.”
This data demonstrates a direct link between anthropogenic climate change and immediate mortality in temperate regions. By attributing 42% of excess deaths to a specific temperature increase of 3–4°C, the study provides a quantitative bridge between global warming trends and local public health crises, suggesting that heat-adaptation strategies in the UK must be accelerated to prevent future spikes in death tolls.
