Videos: Torrential storms cause flash flooding in south-east France

Violent thunderstorms brought torrential rain, strong winds and frequent lightning to parts of south-east France last night (Thursday, August 20). 

Several areas recorded the equivalent of several weeks’ rainfall in just a few hours, with flash flooding sending torrents of water through town centres.

The storms affected parts of Provence-Alpes-Côte d’Azur, the Alps and surrounding areas, while another storm moved towards Corsica early on Friday.

Among the highest rainfall totals recorded were 122.8mm at Levens in Alpes-Maritimes, 102mm at Puy-Saint-Martin in Drôme and 95.4mm at La Faurie in the Hautes-Alpes.

The downpours caused localised flooding, with a video posted on X from Castelnaudary in Aude showing chairs, tables and other objects being swept away by fast-moving water.

The storms also disrupted the cassoulet festival in Castelnaudary, where around 700 people were evacuated to two shelters. Around 20 people were treated for hypothermia by emergency medical teams (although no hospitalisation was required for those treated), while one woman was taken to hospital after being struck in the leg by a falling branch. 

“Heavy thunderstorms in the southeast brought significant rainfall in some areas, with more than 3 weeks to 1 month's worth of rain falling in just a few hours,” La Chaîne Météo wrote on X.

La Chaîne Météo also reported gusts reaching 125km/h at Tarbes in the Hautes-Pyrénées, while Marignana in Corsica recorded 100km/h and Sospel in the Alpes-Maritimes 97km/h.

The storms were especially dramatic along the Côte d’Azur. Meteorologist Anthony Grillon shared videos showing frequent lightning and heavy storms in Var overnight.

In one post, he described an “electrical” atmosphere along the Côte d’Azur. “Incessant lightning and finally rain after 3 months of heat and drought,” he wrote.

A second video showed further storm activity in the Var.

More storms possible on Friday

The unsettled weather is expected to continue in parts of the south-east today (Friday).

Météo-France has placed the Var and Alpes-Maritimes under orange warnings (vigilance - the second-highest level alert) for thunderstorms, heavy rain and flooding. 

On the mainland, stormy rain is affecting the eastern part of the Provence-Alpes-Côte d’Azur region before gradually moving towards Italy.

Conditions should improve during the day, although showers and some instability will remain possible around the Alps and in parts of the southeast.

Temperatures will also be much lower than during the recent spell of extreme heat. Météo-France forecasts a maximum of around 29C in Nice and Ajaccio, with temperatures generally in the mid-20s across much of the country and around 26-30C in Mediterranean areas.

What to do during an orange storm alert 

Météo-France advises people under an orange storm alert to: 

• Stay away from trees and waterways

• Take shelter inside a building 

• Keep up to date with the latest weather warnings

• Avoid unnecessary travel

• Secure objects that could be blown away or damaged by flooding 

• Avoid using telephones and electrical appliances during the storm 

If you are driving, it is important to remember to never drive through floodwater, as the depth and strength of the current can be difficult to judge.

A much calmer weekend ahead

According to La Chaîne Météo, Saturday should bring generally pleasant conditions across France, with temperatures lower than during the recent heatwave. 

The northern half of the country is expected to enjoy generally sunny conditions, with a little cloud and a few showers possible near the Channel. 

The south and Mediterranean coast should see more sunshine, with temperatures generally in the mid-to-high 20s. The southeast is expected to remain warm without a return to the extreme heat experienced for much of the summer.

Winds could still be fairly strong around the Côte d’Azur and Corsica.

Then, on Sunday temperatures are expected to rise again, particularly in southern France, where they could approach 30C in places. The north should remain pleasant and generally dry.

The risk of thunderstorms is expected to be very low with the main possibility limited to the mountainous areas of the Pyrenees.

Unsettled weather could return next week

Early forecasts predict the possibility of a new, more organised spell of rain and thunderstorms from Monday, although the exact location and intensity remain uncertain at the moment.