Forecasters have warned that some places may peak even hotter, with Bordeaux expected to push 43C on Sunday afternoon. There are highs of 39C predicted in the southwest and parts of Nouvelle-Aquitaine may also exceed 40C.
This is the second heatwave in just a few days in southern France.
Northern parts of France could also see temperatures well over 30C on Saturday and Sunday with highs of 35C in Paris as the Olympic Games come to a close.
It will stay hot overnight too from Sunday into Monday with Toulouse staying at 26C and even Paris maintaining 24C.
Temperatures are expected to drop on Monday reaching August norms almost everywhere by Tuesday. Forecasters say the extreme heat will likely be replaced by violent thunderstorms, particularly in the east of the country.
What does an orange heatwave warning mean?
From Friday, French meteorological organisation Météo-France has placed Aude, Gard, Vaucluse, Bouches-du-Rhône and Hérault under an orange heatwave warning. Pyrénées-Orientales has already been under an orange warning since Tuesday.
This is a “non-exceptional but fairly long-lasting heatwave, requiring special vigilance, particularly for sensitive or exposed people” according to Météo-France.
These alerts are part of France's national heatwave warning system, with each colour on the scale activating a particular plan to deal with high temperatures. Departments are on an emergency footing from the orange level.
Though responses vary across the country, these warnings are typically brought in when temperatures exceed a certain limit for three consecutive days. Plans include opening designated cooling spaces in cities and checking on people sleeping rough.
The next level up, a red warning, sees the national government become involved. Local authorities are also given special powers to shut down events and public facilities if needed.
High temperatures also bring fire risk in south-east France
Parts of south-eastern France have also been placed on the second-highest level of alert for forest fires.
Four departments, Bouches-du-Rhône, Vaucluse, Alpes-de-Haute-Provence, and Var, have been listed as on orange forest fire alert by Météo-France. It means they have been determined at high risk of fires breaking out.
The meteorological organisation said that weather conditions have significantly increased the risk compared to normal summer conditions.
Several areas of the Bouches-du-Rhône and Var départements have been closed to visitors as a preventative measure. Restrictions including limited access and prohibitions on work are also in place in several other mountain ranges in the region for safety reasons.
