Storm observatory Keraunos counted more than 14,000 lightning strikes across the country between 12 noon on Tuesday and 3am Wednesday. In the Alps alone, 1,500 impacts were recorded in two hours.

The Auvergne Rhône-Alpes region of eastern France was the hardest hit, with 160,000 homes temporarily without power in Aix-les-Bains and Chambéry.

“Due to the storms, at 10pm, lightning caused faults on an RTE electrical substation and on a power line that supplied Chambéry and Aix-les-Bains,” network operator RTE said in a statement.

“When lightning struck the power line, the line automatically went out of power, to protect the rest of the network.”

De si violents orages qu’il n’y a plus aucun courant sur Challes-les-eaux, Savoie, sauf la haut bien sur #orages pic.twitter.com/Hl3jLM3ygh

— R3siak (@R3siak) August 13, 2024

Meanwhile, in the Côte d’Or département of eastern France, more than a month-and-a-half’s rainfall was recorded in a matter of hours, with weather stations in the area recording more than 100l/m2, or 10cm, of rain. In Haute-Marne, some 70l/m2 of rain (70mm) was reported.

In Isère a 78-year-old man died during the storms in the commune of Pressins – the local mayor said that he had been electrocuted while trying to reconnect his electrical supply.

Also in Isère, holidaymakers were evacuated from a campsite in Morestel because of heavy rains.

Many spent the night in a nearby village hall. The campsite’s manager told local newspaper Le Dauphiné Libéré, as he was ‘knee-deep in water’, following the storm – which he described as ‘a wall of water and wind’.

4h que l’on rentre d’Annecy, 4h d’orage, de pluie, de grêle. Je sais pas si je suis dans une discothèque ou dans un rêve #orages pic.twitter.com/FQbUa7Myf1

— 🇫🇷⚜️ (@IdkButMe_) August 13, 2024

The SNCF network was also disrupted. A Paris-Grenoble train, which left the capital at 7.15pm on Tuesday, was held up in Bourgoin-Jallieu. It arrived four hours late in the Isère capital.

“The train stopped at Lyon, then at Tour-du-Pin due to thunderstorms. A train ahead of us had problems with its windscreen, so the whole line was affected,” Simon Grenier, a passenger on the Paris-Grenoble train, told BFMTV.

Traffic was also very difficult on the A43 motorway, where traffic was temporarily cut off.