Forty people have drowned in heatwave-related deaths in France since Thursday, Prime Minister Sébastien Lecornu has said, as temperatures hit record levels in several major cities and the heatwave reaches a peak in several European countries.

“It’s not something to be taken lightly, going swimming in unsupervised areas during a heatwave,” Sports and Youth Minister Marina Ferrari told French radio.

France, Spain and Italy have been hardest hit by the heatwave so far. France saw its hottest June day on record on Tuesday, reaching an average of 29.8C.

Its hottest night was recorded on Monday, at a minimum average of 21.6C, according to Météo France, and more than half the country is on red alert.

Meanwhile, in Spain temperatures are set to peak above 40C in some areas, with red alerts in Andalusia in the south, and Cantabria and the Basque Country in the north, on the third day of a national heatwave.

Spain is more exposed to the effects of climate change than almost any other European country. State weather service Aemet says June heatwaves are becoming increasingly common, with 10 recorded in mainland Spain between 2000 and 2025, and just two in the previous 25 years.

And in Italy, a red heatwave alert has been declared in 15 cities, including Rome, Milan, Florence, Turin and Venice. The alert signals conditions that can pose health risks even to healthy adults, not just the elderly or chronically ill.

France’s sports minister said too many people were trying to cool off in rivers and canals without necessarily taking the risks into account.

Among the fatalities was a 13-year-old girl who had gone for a dip with her family in the River Seine at Fontaine-La Port on Sunday evening, although she did not know how to swim.

Meanwhile, a young professional footballer was in critical condition in hospital after being pulled out of the River Rhône in a park near Lyon. Emergency services were called to the area to rescue four young men who had got into difficulty in an area of the river where swimming is banned.

Two other deaths on Monday were also blamed on the extreme heat in France, after children aged two and four were found in their family car in a car park in the southern city of Carpentras.

Several people have also drowned in Germany as temperatures are expected to climb as high as 40C in the west and south-west by the end of the week.

The German Lifesaving Association (DLRG) said there were six fatal swimming incidents between Friday and Sunday with men in particular were overestimating their abilities in the water. Three bodies were found in the Rhine near the southwestern town of Biblis, days after three men aged 23, 27 and 50 were reported missing in two different areas of the river.

Spain’s Aemet weather service says temperatures could top 44C in rural areas near the southern city of Córdoba on Tuesday, while in the Ebro valley in the north-east they could exceed 42C. In 101 of Aemet’s 828 weather stations, temperatures hit or exceeded 40C on Monday, with 45C recorded in Andújar.

“There is evidence that heatwaves were now taking place more frequently at the start of summer than in previous decades,” Aemet’s Rubén del Campo told Spanish media.

In Italy the government has revived emergency labour protections aimed at protecting workers most exposed to the sun, including farm and construction workers, from having to work through the hottest hours.

Companies that halt or reduce operations because of dangerous heat waves can now access state-backed furlough support.

Météo France said the red alert in much of France would be extended on Wednesday afternoon from 54 to 58 of the country’s 96 metropolitan departments, to include several areas in the north west.

The president of the Île-de-France region which covers the entire Paris area, Valérie Pécresse, urged people not to travel and to work from home instead: “The rail tracks cannot withstand temperatures above 50C. So we’ll have a lot of disruption to public transport.”

The Eiffel Tower said it was closing early on Tuesday because of the high temperatures forecast in the capital. Instead of staying open until 00:45 at night, it said it was closing at 16:00 (14:00 GMT) and the last entry to the tower was at 12:15. Some 6.75 million people entered the monument last year.

The world's most visited museum, the Louvre, said it was bringing forward its closing time from Wednesday to Saturday from 18:00 to 16:00 local time. The Louvre said its historic building “remains fragile and is not sufficiently adapted to climate change”, adding that the “build-up of heat is at its highest at the end of the day, and intensified by the volume of visitors”.

The heatwave also meant a nuclear power plant in southwest France had to be shut down on Monday night because water temperatures in the River Garonne were set to reach 28C on Tuesday. Under French laws, water used to cool the reactors at the Golfech plant must not exceed that temperature.

Spanish forecasters say temperatures on the Iberian peninsula will start to fall from Wednesday onwards, however they are set to peak in the Netherlands and Belgium, as well as Germany on Friday.

The Dutch weather service, the KNMI, has issued a Code Orange weather alert which refers to a “high chance of dangerous weather” in southern and central areas from Wednesday to Friday.

After meeting on Tuesday, Belgium’s Risk Management Group said it was activating the “alert phase of the national ozone and heat plan” for only the second time. The first occasion was in August 2020, although no specific national measures have been announced, other than to raise awareness and call for extra care for the elderly and children.

Climate change is driving up temperatures around the world – but particularly in Europe. It is the fastest warming content, heating up twice as fast as the global average, according to the Copernicus climate service.

This is causing increased summer heatwaves, greater pressure on Europe’s water supply, and more intense wildfires. Last year, more than 1 million hectares burnt across Europe – a record level – with Spain particularly affected. (BBC)

•The Golfech nuclear power plant in southwestern France had to be shut down on Monday night because of rising temperatures in the River Garonne

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