Records fall by wide margins
An early-season heatwave swept across Europe in late May, shattering hundreds of national and local temperature records. The event was driven by a heat dome — a large high-pressure system that traps hot air drawn from North Africa. Meteorologists noted that many records were not broken by fractions of a degree but by several full degrees.
Portugal recorded 40.3C in Mora on May 26, setting a new national May record and becoming the first European country to hit 40C in 2026. In England, London's Kew Gardens reached 35.1C — beating the previous May record by about 5C and marking the earliest 35C day ever recorded in the UK. Wales set a new May record of 32.9C in Cardiff, and Ireland reached 30.6C at Shannon Airport.
France and central Europe hit hard
France saw over 1,350 heat records broken during the event. Angouleme reached 37.8C, a new national May record. Even Brittany, typically one of the coolest regions in France, saw Brest hit 33.5C — 4 degrees above its previous May record. Austria recorded its hottest May day in over 200 years, with 32.7C in Lienz.
In Spain, more than 200 stations broke monthly records. The night of May 26-27 was the hottest May night on record in Catalonia, with Portbou recording a minimum of 28C.
Health and infrastructure under strain
The heatwave caused a spike in hospitalizations across Portugal, Spain, and Italy. Italy issued its first red alert of 2026 for Rome, Florence, Bologna, and other cities. Health authorities linked several drowning accidents in Britain and France to the extreme heat, as people sought relief in open water.
Europe is warming at roughly twice the global average rate, according to climate scientists. The early arrival of such intense heat has raised concerns about what the rest of the summer may bring. The heat dome has since weakened, but forecasts suggest more unusually warm weather could return in mid-June.