Portugal registered its hottest May day ever this week, with 40.3C measured in Mora on Wednesday, as an intense early-season heat surge spread across western Europe. The record, breaking the country’s previous May high of 40C set in 2001, has intensified concern over public health, infrastructure strain and climate vulnerability before summer has formally begun.
What Happened
Portugal’s national meteorological service said temperatures in parts of the country would still exceed 35C on Friday before gradually easing. The new high in Mora, a town in central Portugal, came amid unusually hot conditions also affecting France, Spain, Germany and Switzerland. In Italy, authorities issued the year’s first red-level heat alert for Rome and four other cities, including Florence, Bologna, Brescia and Turin.
In France, Prime Minister Sébastien Lecornu convened ministers on Thursday to assess preparedness for extreme heat episodes, including wildfire prevention and summer water management. At the same time, a national debate intensified over whether schools and examinations should continue in unsafe indoor temperatures. The baccalaureate exam schedule remained in place, even as some schools closed temporarily.
A primary school in Souston, in France’s Landes region, will stay shut on Friday after classroom temperatures reportedly reached 53C earlier this week, according to local officials cited by French media. Education Minister Édouard Geffray said exam centers could move candidates to shadier rooms and that tests should continue because students had prepared for fixed result timelines. Teachers’ unions criticized the approach, with one educator describing staff as having to bring in personal fans. A secondary school union survey found nearly 78% of schools reported indoor temperatures above 30C, with accounts of teachers using tools to force windows open.
Impact & Consequences
The immediate impact has been felt in schools, transport and public health planning. Seventeen French departments, including Paris and several northwestern areas, were placed under orange alert, a level requiring heightened caution. Paris reached 33C on Thursday and is expected to hit 34C over the weekend. To limit pollution and heat-related traffic pressure, police introduced temporary measures through Saturday, including restrictions favoring lower-emission vehicles, reduced speed limits and a flat fare across the city’s transport network.
Heat stress has also affected elite sport. At the French Open in Paris, world number one Jannik Sinner said he felt dizzy and drained during his match before exiting the tournament. Although he later said it was not solely due to weather, the episode highlighted how rising temperatures are complicating outdoor competition schedules. In Italy, red alerts warned that even healthy, active people could face adverse effects, underlining that this is not just a risk for traditionally vulnerable groups.
Background & Context
Meteorologists have linked the current episode to a heat dome, a persistent high-pressure system that traps warm air and suppresses cooling. Spain’s weather agency said the current temperatures, including expected highs near 35C in Madrid this weekend, are more typical of July or August, even if the event does not yet meet Spain’s formal definition of a heatwave.
Scientists caution that attributing any single heat event entirely to climate change is complex, but they consistently report that global warming is increasing both the frequency and intensity of such extremes. According to the Copernicus climate service, Europe has warmed by roughly 0.56C per decade over the past 30 years. That pace of warming has made temperature spikes more severe, longer lasting and more disruptive to daily life, from schooling to energy demand and water management.
International Response
Governments and multilateral institutions are increasingly framing severe heat as a strategic risk rather than a seasonal inconvenience. France’s ministerial review focused on emergency readiness, wildfire response and water security, while Italian authorities moved quickly to issue top-tier heat warnings in major urban centers. These measures reflect broader shifts toward earlier intervention as heat arrives sooner in the year.
At the global level, the United Nations warned on Thursday that average world temperatures are likely to remain at or near record levels this year and over the next four years. The UN’s weather and climate agency has said the 11 warmest years on record have all occurred since 2015 and that another all-time annual temperature record is likely before 2031. Those forecasts are reinforcing pressure on governments to accelerate adaptation planning, especially in cities vulnerable to sustained high heat.
What to Expect Next
Forecasters expect temperatures in parts of Portugal to begin easing after Friday, but heat is likely to persist across sections of western and southern Europe through the weekend. Authorities are expected to maintain alerts, monitor hospitals and review school and transport protocols as conditions evolve. The key question now is whether this episode proves a brief spike or a signal of increasingly frequent early-summer extremes demanding permanent policy changes.
