Europe heat dome drives record-breaking temperatures across Britain and France

A stubborn blocking high-pressure system has locked hot air over Europe, turning what should have been an ordinary June into a protracted spell of dangerous heat. The pattern has pinned in place a heat dome over Britain, France, Spain and Italy, leaving the same air mass to intensify day after day and putting health systems, transport networks and power demand under sustained strain.

In Britain, the Met Office issued a Red Extreme Heat Warning for Wednesday and Thursday, with Amber warnings in force from Monday through Thursday across parts of southern and central England and Wales. Forecasters said temperatures in southern England were set to reach 34C on Monday, 37C on Tuesday and at least 39C at the peak, close to a national June record of 35.6C set in Southampton in 1976 and matched at Camden Square in 1957.

The forecast also pointed to widespread tropical nights, when temperatures do not fall below 20C. That matters as much as the daytime highs: bodies recover poorly without overnight cooling, and prolonged heat leaves hospitals, rail systems and electricity grids under pressure for longer than a brief afternoon spike would.

The Met Office said the UK sat on the boundary between the hot high-pressure system to the south and lower pressure to the north, helping explain why temperatures varied sharply from one part of the country to another. That contrast has become one of the clearest markers of the current European heat episode, with the south baking while other areas remain less extreme.

France has faced some of the harshest conditions. The Associated Press reported daytime highs above 40C and hot nights that have already made sleep difficult, while Reuters said France placed emergency services and military forces on wildfire alert. French authorities also restricted public alcohol consumption and outdoor sports in some areas as the heat wave intensified, and schools closed or shortened hours in parts of Europe.

The wider pattern has not been a one-off burst. Late May temperatures in western Europe ran about 10 to 15C above normal, several records were broken across the region, and Paris recorded its hottest May day since measurements began. The current episode was already the second major period of extreme heat in Europe this year, a sign that the continent is moving deeper into a summer pattern of more frequent, longer-lasting and more disruptive heat domes.