Western Europe saw its hottest June on record as two massive heatwaves swept across the continent, the EU's Copernicus Climate Change Service said on Tuesday.
Average temperatures reached 20.49 degrees Celsius, above the previous record of 20.43 degrees in 2003.
"June 2025 saw an exceptional heatwave impact large parts of western Europe, with much of the region experiencing very strong heat stress," said Samantha Burgess from the European Centre for Medium-Range Weather Forecasts (ECMWF), which runs the EU service.
"This heatwave was made more intense by record sea surface temperatures in the western Mediterranean," she added. "In a warming world, heatwaves are likely to become more frequent, more intense and impact more people across Europe."
Globally, the month was the third warmest June on record, after 2023 and 2024, with average surface air temperatures of 16.46 degrees.
Air temperatures in June 2025 were above average in large parts of western and central Europe, the report found.
Two strong heatwaves hit large parts of western and southern Europe in mid-June and at the end of the month.
An exceptional marine heatwave developed in the western Mediterranean, leading to the highest daily average sea surface temperature ever measured in the region, at 27 degrees.
Copernicus also reported that the extent of Arctic sea ice was 6% below average, the second-lowest monthly figure for June since satellite records began 47 years ago.
Antarctic sea ice extent was 9% below average, the third-lowest extent ever recorded for the month.
The European Union's Copernicus Climate Change Service regularly publishes data on the Earth's surface temperature, sea ice cover and precipitation.
The findings are based on computer-generated analyses that incorporate billions of measurements from satellites, ships, aircraft and weather stations around the world.
