People cool off and relax at a fountain in front of the Eiffel Tower in Paris, France, June 23, 2026. The Eiffel Tower in Paris closed early on Tuesday due to high temperature. (Photo: Xinhua)

A boy jumps into a fountain in front of the Eiffel Tower in Paris, France, June 23, 2026. The Eiffel Tower in Paris closed early on Tuesday due to high temperature. (Photo: Xinhua)

Children cool off and relax at a fountain in front of the Eiffel Tower in Paris, France, June 23, 2026. The Eiffel Tower in Paris closed early on Tuesday due to high temperature. (Photo: Xinhua)

People cool off and relax at a fountain in front of the Eiffel Tower in Paris, France, June 23, 2026. The Eiffel Tower in Paris closed early on Tuesday due to high temperature. (Photo: Xinhua)

The night from Monday to Tuesday was the hottest recorded in France since national meteorological records began in 1947, with the national nighttime heat indicator, calculated from data at 30 meteorological stations across the country, reaching 21.6 degrees Celsius, Meteo-France said on Tuesday.

According to the meteorological institute, 54 departments in mainland France were placed under red heatwave alert, the highest alert level, on Tuesday, while 35 departments were placed under orange alert.

French Prime Minister Sebastien Lecornu said on Tuesday that around 40 people have drowned in France since June 18, mostly young people, news channel BFMTV reported. He also said that an interministerial crisis unit has been mobilized to respond to the heatwave.