An unseasonable and intense heatwave has swept across Europe, pushing temperatures to historic highs and prompting governments to issue urgent health warnings. Portugal recorded its hottest May day on record on Wednesday, with the central town of Mora — a small municipality in the Alentejo region — reaching 40.3°C, surpassing the previous national May record of 40°C set in 2001. Across the continent, Italy issued red heatwave alerts for Rome, Florence, Bologna, Brescia and Turin — the first such alerts of the year — while seventeen departments in France, including those around Paris, were placed under orange alert. Temperatures in the French capital reached 33°C on Thursday and are forecast to peak at 34°C over the weekend.
The immediate meteorological cause is a "heat dome" — a region of high pressure that stalls over an area, trapping warm air beneath it. Though scientists caution against attributing any single weather event directly to climate change, there is clear evidence that climate change is making such events more frequent and more severe. Europe has been warming at 0.56°C per decade over the past 30 years, according to the Copernicus climate service — more than twice the global average rate, making it the world's fastest-warming continent. A UN-backed report warned on Thursday that global average temperatures are likely to remain at or near record levels for at least the next four years, with a new all-time hottest year considered likely before 2031.
The heat is disrupting daily life across the region. In France, where baccalaureate exams are proceeding despite the conditions, a primary school in Souston, in the southwestern Landes region, was forced to close after internal temperatures reached 53°C. Education unions have criticised the government's decision to press ahead with national exams, with teachers reportedly bringing their own fans to classrooms. French Prime Minister Sébastien Lecornu chaired an emergency ministerial meeting to plan for extreme heat events, covering forest fire risk and summer water supplies. Paris authorities restricted traffic and introduced a single-fare public transport system to ease congestion and encourage people off the roads. At the French Open tennis tournament, world number one Jannik Sinner withdrew from his match, citing dizziness and fatigue that he attributed to the conditions.
The health toll of European heatwaves is well documented and sobering. In 2022, heat-related summer deaths across Europe included more than 18,000 in Italy, over 11,000 in Spain, and more than 8,000 in Germany. Extreme heat is now considered the deadliest weather and climate-related hazard in Europe — claiming more lives than floods or storms. Yet new research from England suggests that public warning systems are falling short: around 41% of people failed to take any protective action when heat-health alerts were issued, and roughly 30% never saw the alerts at all. Older adults and lower-income households — precisely those most vulnerable — were the least likely to receive or act on warnings, in part because alerts are disproportionately distributed through digital channels that these groups are less likely to use.
The findings carry lessons beyond the United Kingdom. As heatwaves become a fixture of European summers rather than an exception, experts argue that governments must not only upgrade infrastructure — improving building insulation and expanding green urban spaces — but also fundamentally rethink how heat risk is communicated to the public. In cultures where warm weather has long been welcomed rather than feared, persuading people to treat 35°C as a genuine danger rather than a pleasant summer's day remains one of public health's most pressing challenges.