Europe is bracing for a “warmer than normal” August after a series of back-to-back heatwaves.
Much of the continent has struggled to cope with this situation, as temperatures soared above 40°C in recent weeks, creating ideal conditions for the fires that have devastated large parts of France and Spain and caused the evacuation of hundreds of thousands of citizens.
But the chances of much-needed relief from the high temperatures look unlikely, as early forecasts warn that further heatwaves are possible.
Will Europe still be hot in August?
“Since their early July numbers, the seasonal updates tilt all odds towards a warmer-than-normal August across Europe and agree that the strongest and most certain heat signal is over the Mediterranean and Southeastern Europe,” Ioanna Vergini, founder of weather forecasting platform WFY24, tells Euronews Earth.
This includes “recurrent heat clusters” such as Iberia, Italy, Greece and parts of the Balkans.
“The unusually warm Mediterranean Sea is leaving its mark on the land and in some places it appears at night instead of in the afternoon,” Vergini adds.
WFY24 forecasts for the first few days of August predict that Naples, Barcelona, Rome, Valencia, Nice, Thessaloniki, Split and Athens will stay above 20°C every night.
This is classified as a tropical night, which can increase the risk of severe heat stress – especially among vulnerable populations.
Even further north, scorching temperatures are on the horizon. The UK Met Office is warning that maximum temperatures of 35°C are expected in August as the mercury soars.
“Temperatures will probably be above normal and some periods of hot weather and heatwaves are possible, particularly in the south,” its long-term weather forecast adds.
How do scientists know if climate change is behind extreme weather?
Advances in weather and climate data have made it easier for scientists to assess the impact of global warming on extreme events like heat waves and floods. This is often called extreme event attribution.
Since there are many interacting factors, including natural triggers like El Niño, studies of attribution of extreme events do not seek to find whether climate change directly caused a heat wave, but rather how warming temperatures have influenced the event.
This is often done by comparing how often an extreme event occurs today compared to how often it would have occurred in a world without human-caused climate change.
Researchers will also explore how climate change changed the characteristics of an extreme weather event – such as whether a heat wave became hotter due to heat-trapping gases.
For example, a rapid attribution analysis by World Weather Attribution (WWA) used observed and forecast temperature data to analyze the hottest three-day period in a large area of Europe that was blanketed by scorching temperatures in late June.
Scientists concluded that both maximum daytime and nighttime temperatures would have been “virtually impossible to occur at this time of year” until 1976, just 50 years ago.
The analysis also found that a similar heat wave that occurred 50 years ago would have been 3.5°C colder than last month’s.
Scientists have what is called “high confidence” when it comes to extreme heat, because of the amount of data and understanding we now have about climate change.
“Continued fossil fuel emissions are directly responsible for the disruption people are experiencing in their homes, schools, and workplaces,” says Dr. Keeping.
“The speed of change is staggering. Every few years we see heat records broken in Europe. This year it has been in consecutive months,” he added.
For weather hazards like tornadoes and large hail, data is less complete. This makes it more difficult to confidently attribute their occurrence.
Attribution studies are also used to show the consequences of extreme weather caused by climate.
An analysis by Imperial College London, the UK Met Office and the London School of Hygiene and Tropical Medicine recently used weather data, climate models and studies of excess mortality during heatwaves to measure the impact of the last two heatwaves.
Researchers estimate that maximum daytime temperatures were 3°C to 4°C higher than they would have been without global warming – resulting in 10,000 excess deaths.
“Extreme heat is breaking records across Europe and the science is very clear about why: climate change is spreading rapidly, driven by the world’s addiction to burning coal, oil and gas,” says Simon Stiell, UN Climate Change Executive Secretary.
What other factors influence extreme weather?
Many reports on extreme weather, particularly heat waves, focus on the atmospheric pattern behind the event – rather than the cause.
For example, in May, France’s Météo-France weather agency blamed temperatures of 40°C on a “heat dome.”
This occurs when a high-pressure system develops in the upper atmosphere, causing the air below it to descend and compress, increasing temperatures in the lower atmosphere.
Since hot air expands, this creates a puffy dome that traps the heat inside.
Winds are normally able to move high pressure around, but due to the extension of heat domes into the atmosphere, the weather system becomes almost stationary.
However, a 2025 study published in the Proceedings of the National Academy of Sciences found that atmospheric patterns that trigger extreme weather, such as heat domes and floods, have nearly tripled since the 1950s due to human-caused climate change.
An analysis by Climate Central in 2023 also found that a heat dome that caused temperatures to reach 48°C in parts of Mexico and the southern US became at least five times more likely due to climate change.
What impact does El Niño have on heat?
El Niño (Spanish for ‘the boy’) is a natural phenomenon that can cause extreme weather. Earlier this year, the US National Oceanic and Atmospheric Administration (NOAA) declared that El Niño conditions were officially developing in the tropical Pacific.
El Niño occurs when sea temperatures in the eastern Pacific Ocean become unusually warm and typically plagues Regions in the tropics. It is often linked to extreme weather events, although experts warn it is being used as a “distraction” from global warming.
When El Niño conditions form, flooding is a common hazard in South America, such as northern Peru, and can reach parts of East Africa, Central Asia, and the southern United States.
The risks of droughts and forest fires also increase during El Niño, especially in much of Australia, northern parts of South America, and in Asian countries such as Indonesia.
Most El Niño events have temporarily increased global average temperatures by about 0.2℃. This is not as significant as human-caused climate change, which has increased global surface temperatures by approximately 1.3-1.5℃ compared to pre-industrial levels.
The year 2025 was the third warmest year on record – hotter than the 2016 El Niño – despite the cold current that naturally forms from a La Niña (Spanish for ‘girl’) event.
La Niña typically cools global temperatures by strengthening trade winds and drawing colder water from the ocean depths to the surface along the equatorial Pacific. It also occurs irregularly, but tends to last longer than El Niño.
Are the low pollution levels after Europe’s hot summer?
Following the hot start to the summer in Europe, several prominent news organizations declared that the successive heat waves were caused by a drop in pollution levels.
The claim was shared online by Richard Tice, vice-chairman of the right-wing populist party Reform UK, and has been used to criticize the country’s efforts towards net zero.
It stems from a study published in the scientific journal Geophysical Research Letters, which does not include data on recent heat waves.
The drop in pollution could reduce the cooling effect of aerosols, which absorb or reflect sunlight. However, Professor Erich Fischer, a climate scientist at ETH Zurich, tells Carbon Brief that attributing this to the heatwaves in Europe is “wrong”.
“Heatwaves are caused by high-pressure systems and are now much more frequent and intense because they are occurring in a climate that is much warmer than 100 years ago as a result of warming caused by greenhouse gases,” he added.
“The article shows that the warming of summer caused by greenhouse gases was temporarily masked by air pollutant aerosols. The full extent for European summers is only now becoming apparent, as air pollutant aerosols have fallen,” he emphasized, among other things.