PARIS: Six French departments were placed on red alert for flooding amid “exceptional rain” that the French weather agency said was as much as 630 mm (24.8 inches) in 48 hours in one area.
Departments in France are administrative regions similar to British or American counties.
The areas covered by the red alert include Lyon, the third-largest city in the country, as well as Cannes, famed for its film festival.
Authorities said they had closed roads, evacuated neighborhoods and asked residents to avoid placing themselves in danger by taking photos and videos.
There have been no reports of deaths or injuries and it is not yet clear what the level of damage is from the floodwaters.
The flooding in the southern part of France comes a week after remnants of Hurricane Kirk churned across western Europe and nearly a month after Cannes was hit by flash flooding.
Earlier in September, central Europe was battered by the worst floods in that area in at least two decades.