Europe experienced one of its most extreme summers on record in 2026, with persistent heat, dry conditions and exceptionally warm seas affecting large parts of the continent.
By the end of the season, 52% of Europe had experienced at least ‘very strong’ heat stress, corresponding to feels-like temperatures of 38°C or higher.
The findings come from the Copernicus Climate Change Service (C3S), implemented by the European Centre for Medium-Range Weather Forecasts (ECMWF), alongside the Copernicus Emergency Management Service (CEMS).
Their latest results also show record temperatures across western Europe, exceptionally low river flows and an unusually active wildfire season.
The prolonged heat helped Europe record its third-warmest summer on record, while western Europe experienced its warmest summer since records began.
The combination of high temperatures, dry conditions and warm seas created widespread impacts across human health, waterways, industry and ecosystems.
Samantha Burgess, Strategic Lead for Climate at ECMWF, explained: “Europe experienced a summer of compounded climate extremes in 2026. Record heat stress, widespread dry conditions, exceptionally low river flows, and unusually warm seas occurred together across large parts of the continent.
“The consequences extended far beyond temperature records, affecting water availability, energy systems, transport, ecosystems and human health. As the climate continues to warm, events like these underscore the importance of building resilience to increasingly interconnected climate risks.”
Western Europe breaks temperature records
The heat arrived unusually early, with the first major heatwave affecting large areas of western Europe in late May. Exceptionally warm conditions then persisted throughout the summer, with record daily temperatures also recorded in May and September.
Western Europe recorded an average summer temperature of 21.7°C, which was 2.5°C above the 1991–2020 average. This surpassed the previous record, set in 2003.
The scale and persistence of the heat were also notable. During 2026, there were 17 days when at least 60% of western Europe recorded temperatures above 30°C. This compares with 11 such days in 2003 and seven in 2025.
Heat stress was similarly widespread. Across western Europe, ‘strong’ heat stress was recorded for a record 41 days by the end of summer, five more than in 2003. ‘Very strong’ heat stress was recorded for 13 days, also setting a new record.
Dry conditions drive river lows and wildfires
The combination of repeated heatwaves and persistent dryness contributed to an exceptionally active wildfire season.
By 2 September, the area burned across the European Union was almost twice the 2006–2025 average for that point in the year, according to the European Forest Fire Information System (EFFIS). Spain and France experienced particularly extensive wildfire activity.
Copernicus Atmosphere Monitoring Service (CAMS) data showed that wildfire emissions across Europe by the end of summer were among the 10 highest recorded since 2003. The fires also exposed millions of people to dangerous levels of air pollution.
Meanwhile, Europe experienced its most severe summer of low river flows since records began under the European Flood Awareness System (EFAS) in 1992. Major rivers including the Rhine, Danube, Po, Loire, Rhône and Seine reached record or near-record low levels during July and August.
The low flows disrupted cargo transport and supply chains while increasing pressure on irrigation, nuclear reactor cooling, hydropower generation and freshwater availability.
Warm seas worsen heat stress
European seas also experienced exceptionally high temperatures during the summer, with record or near-record sea-surface temperatures recorded along much of the Atlantic coast and across the western and central Mediterranean.
These conditions were accompanied by strong to exceptional marine heatwaves, referring to prolonged periods of unusually warm ocean temperatures.
Warm seas can also affect conditions on nearby land. Marine heatwaves can limit nighttime cooling and increase humidity in coastal areas, potentially making heat feel more intense and worsening heat stress.
Together, the land, river and ocean observations show how the extreme conditions of Europe’s 2026 summer extended beyond air temperatures, affecting multiple interconnected parts of the continent’s environment and infrastructure.
