Western Europe endures its warmest June ever recorded as heat extremes intensify, EU climate body reports

Burgess pointed to unusually high humidity as a major factor behind the severity of the June heatwave.

Western Europe just recorded its hottest June on record, according to the European Union’s climate monitoring service, as an intense heatwave gripped the continent and a fresh wave of extreme heat now moves across the region.

The European Centre for Medium Range Weather Forecasts, which runs the Copernicus Climate Change Service, reported that average temperatures across western Europe reached 20.74 degrees Celsius in June, more than three degrees above the average recorded between 1991 and 2020. The figure surpasses the previous record set in June of last year and arrives amid a pattern of escalating heat events, following an unusually early hot spell in May and now another heatwave striking the continent this week.

Samantha Burgess, strategic climate lead at the forecasting center, said the world will continue seeing more frequent heatwaves as global temperatures rise. She said these events will grow more intense, last longer, and affect broader geographic areas over time.

Copernicus data placed June as the second hottest ever recorded both globally and across Europe as a whole, continuing a long term trend driven by human caused climate change. Global temperatures for the month measured 1.39 degrees Celsius above the estimated pre industrial average, a baseline period spanning 1850 to 1900. The world’s oceans also recorded their warmest June on record, a trend unfolding alongside a developing El Nino pattern that forecasters expect to strengthen across the tropical Pacific in coming months.

Burgess described the shift as a turning point in how people experience climate change, saying the phenomenon has moved from an abstract concern documented in scientific reports into a tangible force disrupting daily life.

A high pressure system that meteorologists describe as a heat dome settled over much of Europe during June, trapping hot air much like a lid over a pot of boiling water. The system produced record breaking temperatures in multiple countries, both for the month of June specifically and in some cases for any month on record. Health officials linked thousands of deaths to the heatwave, with the highest tolls reported in France, Spain and Belgium.

An analysis found that more than two thirds of the European population, roughly 410 million people, experienced temperatures exceeding 35 degrees Celsius at some point during the heatwave that ran from June 15 through June 30. Copernicus noted that the extreme heat contributed to serious health consequences across the continent, including a significant number of heat related deaths.

A separate report from the advocacy group Global Witness found that nearly 300 million people faced potentially harmful levels of ozone pollution during the same period, including roughly 100 million children and elderly residents who face heightened vulnerability to air quality problems during extreme heat.

Burgess pointed to unusually high humidity as a major factor behind the severity of the June heatwave. She explained that the heavy moisture in the air prevented temperatures from dropping meaningfully overnight, producing a string of consecutive tropical nights that offered residents little relief from the daytime heat.

The Mediterranean Sea experienced its own record breaking marine heatwave during the period, while Europe’s Atlantic coastline also endured unusually hot conditions that placed marine and coastal ecosystems under strain. Burgess noted that warmer sea temperatures reduce the cooling effect that coastal areas typically receive at night, since the absence of a temperature gap between land and water eliminates the sea breeze that normally brings relief.

Dry conditions across eastern Europe raised the risk of drought in that region, while the same weather pattern fueled wildfire activity across the Iberian Peninsula and southern France, according to Copernicus.

World Weather Attribution, a research network made up of climate scientists, concluded last month that the June heatwave ranked as the most severe ever documented across the region, based on an analysis of average peak temperatures over a three day forecast window. The group said a heatwave of this intensity would have been virtually impossible without the influence of human driven climate change, and it calculated that a comparable event in June 2003 would have registered roughly two degrees cooler.

Burgess said Europe urgently needs adaptation strategies to cope with the changing climate, noting that many historic buildings across the continent were constructed centuries ago under climate conditions that no longer exist. She said global efforts must accelerate toward reaching net zero emissions from fossil fuel combustion as quickly as possible, warning that heatwaves will continue worsening as long as fossil fuel emissions keep entering the atmosphere.

The consecutive waves of extreme heat this year, spanning an early spring hot spell in May, the record breaking June heatwave, and the fresh heat event now affecting the continent, illustrate a pattern that climate scientists say reflects Europe’s position as the fastest warming continent on Earth. Researchers attribute this accelerated warming partly to shifts in atmospheric circulation patterns that are making prolonged heat events increasingly common across the region.