In western Europe the average temperature record for the June-July period hit 21.62C, Copernicus said.
That figure was 2.79C above the June average for 1991 to 2020.
The extreme heat has contributed to major wildfires, prolonged drought and new national temperature records across the region, as well as thousands of projected heat-related deaths.
Globally, so far 2026 is the third-hottest year, behind 2024 and 2025, climate statistics show.
Last month saw the highest average sea surface temperature ever recorded for July across the extra-polar oceans, or the oceans free of seasonal sea ice, Copernicus said.
That was partially fuelled by developing El Nino conditions in the equatorial Pacific, the service said. The new average record for July is 20.96C, which beat the 2023 record of 20.89C.
But last month's average surface air temperature globally was 16.90C, making it only the joint second warmest July on record and tied with July 2024, Copernicus reported.
"Persistent high-pressure systems trapped heat over western Europe, the extreme temperatures also amplified widespread drought. As soils dry out, they lose their ability to provide natural cooling, allowing heat to build more readily," said Samantha Burgess, strategic lead for climate at the European Centre for Medium-Range Weather Forecasts.
"This is a clear example of how climate change is intensifying heat extremes, with heat and drought increasingly reinforcing one another."
River levels were well below long-term averages across large parts of the affected dry regions, with the Seine, the Rhine and the Danube among those most severely affected, Copernicus said.
The Copernicus Climate Change Service publishes regular data on topics including surface air temperature, sea ice cover and precipitation. Its findings are based on computer-generated analyses drawing on billions of measurements from satellites, ships, aircraft and weather stations around the world.
with DPA
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