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.

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 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.