
Europe faced temperatures of up to 40°C (104°F) on Sunday (28 June) as storms swept other areas, with France reporting 1,000 excess deaths in a record-breaking heatwave.
Its public health agency said most heat-related fatalities involved older people and warned the toll was expected to rise as more details emerged from residential care and private homes.
Scientists described the heatwave, which began on 20 June, as the worst recorded in Europe.
They said the extreme heat had disrupted power generation, damaged infrastructure and overwhelmed healthcare systems, and would have been "virtually impossible" without human-caused climate change, which has made this week's soaring night-time temperatures 100 times more likely than two decades ago.
"Right now, 150 million people are living under extreme heat, hundreds have died, schools are shut, grids are buckling," World Health Organisation Director-General Tedros Adhanom Ghebreyesus said on X.
"Driven by climate change and global warming, the phenomenon of the 'once-in-a-generation' heatwave is now occurring nearly annually.
We were warned," he wrote, adding that Europe's homes, workplaces and schools were ill-equipped for extreme heat.
Temperature records were broken in Austria, the Czech Republic, Germany and Poland, while storms in France added to the disruption to travel and power supplies.
In Germany, trains were reduced on a major line in North Rhine-Westphalia, and trams were suspended in Leipzig, as local media reported many people stayed indoors until sunset.
In Rome, Pope Leo XIV thanked worshippers for attending Sunday's prayer in Saint Peter's Square despite the heat.
Europe's rivers were also depleted and warming, creating problems for electricity generation and agriculture.
Hungary's Paks nuclear power plant again reduced output because of the high temperature of the Danube River, which it uses as a coolant.
In Italy, the River Po's flow dwindled, allowing seawater to move 18 km (11 miles) inland and raising concerns for agriculture and protected wetlands in the delta.
Dozens of people seeking relief from the heat were reported to have drowned.
In Italy, rescuers were searching for the husband of cabinet minister Eugenia Roccella, who went missing on Saturday while swimming in Lake Vico, 70 km (44 miles) from Rome.
Czech authorities urged people to avoid physical activity and issued smog warnings in central and northern parts of the country because of high ground-level ozone caused by the heat.
Meteorologists said thunderstorms could hit parts of France, Germany and the Czech Republic over the next day or two, while cooler weather was forecast for much of Western Europe as the heatwave moved deeper into Central Europe and the Balkans.
France's weather agency said extreme heat had eased in most parts of the country, although some areas in the north-east remained under a heat advisory.
Health Minister Stéphanie Rist told La Tribune that the impact could last for as long as 10 days after the weather had ebbed.
"The episode is not finished," she told BFM.
Storms that hit parts of France late on Saturday brought cooler air but also caused power cuts.
On Sunday afternoon, 36,000 households in northern and central France were without power, electricity provider Enedis said.
Reuters