Western Europe sweltered through its hottest June on record last month, as “extreme” temperatures blasted the region in punishing back-to-back heatwaves, the EU climate monitor Copernicus said Wednesday. Globally, this June was the third-warmest on record, continuing a blistering heat streak in recent years as the planet warms as a result of humanity’s emissions of greenhouse gases.
The previous hottest June was in 2024, and the second hottest was in 2023, the Copernicus Climate Change Service (C3S) said. Sweltering extremes were particularly pronounced in Europe, which is warming several times faster than the global average.
Spain and Portugal record temperatures of up to 46°C
Millions of people were exposed to high heat stress across parts of the continent as daily average temperatures in Western Europe climbed to levels rarely seen before, and never so early in the summer. Several countries recorded surface temperatures above 40 degrees Celsius, with heat of up to 46°C in Spain and Portugal, Copernicus said.
An analysis of Copernicus data found that 12 countries and around 790 million people around the world experienced record heat last month.
Southern Spain is the worst-affected region, with temperatures in the mid-40s Celsius recorded in Seville and neighboring areas. Doctors have expressed alarm at the combination of hot days and uncomfortably warm nights, which can place a lethal stress on the human body. In Portugal, a reading of 46.6°C was registered in Mora last month, about 60 miles east of Lisbon. Weather officials were working to confirm whether that marked a new record for June.
Second-warmest May on record
The world also experienced its second-warmest May since records began this year, a month in which climate change fuelled a record-breaking heatwave in Greenland. May was Earth’s second-warmest May on record, exceeded only by May 2024, rounding out the northern hemisphere’s second-hottest March-May spring on record.
Global surface temperatures in May 2025 averaged 1.4 degrees Celsius higher than in the 1850-1900 pre-industrial period, when humans began burning fossil fuels on an industrial scale, C3S said. That broke a run of extraordinary heat, in which 21 of the last 22 months had an average global temperature exceeding 1.5°C above pre-industrial times, although scientists warned this break was unlikely to last.
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Europe’s heatwaves cause 2,300 deaths
The impact of the record temperatures was felt across Europe where around 2,300 people died of heat-related causes across 12 cities during the severe heatwave that ended last week, according to a rapid scientific analysis published on Wednesday. The study targeted the 10 days, ending 2nd July, during which large parts of Western Europe were hit by extreme heat, with temperatures breaching 40 degrees Celsius in Spain and wildfires breaking out in France.
Of the 2,300 people estimated to have died during this period, 1,500 deaths were linked to climate change, which made the heatwave more severe, according to the study conducted by scientists at Imperial College London and the London School of Hygiene and Tropical Medicine.
“Climate change has made it significantly hotter than it would have been, which in turn makes it a lot more dangerous,” said Dr. Ben Clarke, a researcher at Imperial College London.
The study covered 12 cities, including Barcelona, Madrid, London and Milan, where the researchers said climate change had increased heatwave temperatures by up to 4 degrees Celsius. The researchers used established epidemiological models and historical mortality data to estimate the death toll, which reflects deaths where heat was the underlying reason for mortality, including if exposure exacerbated pre-existing health conditions.
