The scorching heat that persistently baked western Europe this summer was the worst on record, a report has found, with more than half the continent seared by “very strong” heat stress that felt hotter than 38C.

Surface air temperatures in western Europe from June to August were 2.5C above the recent decadal average, according to an update from the EU’s Copernicus climate monitoring service on Friday, while milder but still deadly heat across the rest of the continent made the summer Europe’s third hottest on record.

The finding comes as a swelling El Niño of unprecedented strength raises global temperatures and supercharges violent weather from South America to Australia. The natural sea warming pattern, which has broken the temperature record months before its expected peak at the end of the year, is expected to cause almost half a million extra heat-related deaths by February.

In Europe, where El Niño’s effects are felt mostly indirectly – for instance, through higher food prices and inflation – the intense heat experienced this summer is the result of fossil fuel pollution clogging the atmosphere.

The report found at least 60% of western Europe suffered through temperatures above 30C on 17 days this summer. In 2003, a year also marked by ferocious heat, this was observed on 11 days, and in 2025 on just seven. The high heat led to a record-breaking 13 days of “very strong” heat stress across western Europe.

Europe saw an abnormally early start to summer-like weather when a powerful heatwave boggled climate scientists in late May, and high heat continued even through September, the report found. Recurring heatwaves, made hotter and more common by climate breakdown, killed tens of thousands of people across the continent while ruining harvests and shutting power plants.

“The consequences extended far beyond temperature records – affecting water availability, energy systems, transport, ecosystems and human health,” said Samantha Burgess, a climate scientist at the European Centre for Medium-Range Weather Forecasts. “As the climate continues to warm, events like these underscore the importance of building resilience to increasingly interconnected climate risks.”Compounding extremes of heat, drought and fire proved particularly damaging. European sea surface temperatures this summer also broke records, the report found, while the continent’s rivers experienced their lowest summer flows in more than 30 years. Hot weather and widespread drought helped wildfires run rampant.

The severity of fire weather conditions in 2026 was the worst that scientists have ever recorded, data published by the European Forest Fire Information System on Wednesday showed. By the end of September, the 680,000 hectares that were burned made it the third-worst on record, behind the million hectares burned by this time of year in 2025 and the 768,000 hectares burned in 2022.

Smoke, one of the greatest environmental threats to human health, spewed 30% more fine particulate matter into the air than the average over the last two decades.

“Frankly, after the summer we’ve just had, there’s little new to say,” said Xavier Rodó, who leads the climate and health programme at ISGlobal, a Spanish research institute, who was not involved in the report. “This surge in the number and intensity of extreme weather events is clearly indicative of unprecedented changes in the European climate, as many records have been broken, not only locally, but also regionally and continentally.”To stave off the heat, doctors and climate scientists have called on governments to stop burning fossil fuels, shade buildings, green cities, and install air conditioning in hospitals, schools and care homes.