Temperatures could reach record levels in the southwest of the country, with firefighters battling wildfires and thousands forced to evacuate.
Blazes in Spain, Portugal, and Greece have forced thousands more to flee.
Document temperatures are also expected in parts of the UK, which has its first-ever red extreme heat warning in place.
Wildfires in France in recent days have forced over 16,000 people to flee the area, with emergency shelters set up for evacuees.
Gironde, a popular tourist region in the southwest, has been hit particularly badly, with firefighters battling to control fires that have demolished over 14,000 hectares (34,000 acres) of land since last Tuesday.
The heatwave prompted warnings of what one meteorologist described as “an apocalypse of heat” in some areas of the southwest.
Elsewhere in Spain and Portugal, more than 1,000 deaths have been attributed to the heat in recent days.
In southern Spain, more than 3,200 people fled fires in the Mijas hills, though around 2,000 of them have since returned house.
Wildfires have also broken out in the provinces of Castilla y León, Galicia, and Extremadura. The Spanish Prime Minister Pedro Sanchez is due to visit the latter region on Monday.
Fires in Portugal have been largely stopped, despite temperatures there hitting 47C (116F) on Thursday – a record for July.
In the UK, a red extreme heat warning is in place for the first time.
Enrique Sanchez, the Dean of the Faculty of Environmental Sciences and Biochemistry at The University of Castilla-La Mancha in Spain told the BBC that heatwaves would soon become the norm.
“In the long term, I mean in the following years, there is no way that the temperatures are going to (not) increase, so heat wave events will become more and more common… all along Europe,” he said.
Dr. Sanchez said measures could be taken to mitigate the effects of the heat, but he added the real solution was in fighting climate change.
“Authorities have to act against climate change and at the same time adapt buildings to be ready for air conditioning for example,” he said.