At least 845 schools will be closed, French Education Minister Édouard Geffray said on Sunday, while around 1,800 will cut classes short.
Most of those affected are in the 49 departments where France's national weather service has declared a maximum "red alert" for extreme heat, including the entire Paris region, all of the west coast and swathes of the centre and south.
It represents France's most extensive red alert to date. Another 40 departments are on the second-highest alert level.
Météo France has cautioned that Monday could be "among the hottest days ever recorded across France", with temperatures forecast to climb as high as 41C.
"Monday and Tuesday are likely to be very hot. We are likely to break temperature records and remain at very high levels," Mathieu Lefèvre, France's minister for ecological transition, told a press conference on Sunday.
"We do not expect temperatures to drop by the end of the week."
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Exam period
Asked if he would order schools closed nationwide, Geffray told broadcaster France 3 that decisions should be taken at local level. In some cases, schools can be better adapted to protect children from extreme heat than housing, he noted.
The heatwave comes as hundreds of thousands of French high school students prepare to sit oral exams this week for their baccalaureate.
The Île-de-France region that includes Paris has announced €1 million of emergency funding to help exam centres buy cooling equipment. High school students in Quimper sit written exams for the French baccalaureate on 15 June 2026.
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Much of France has been on red alert since Sunday. Météo France extended its maximum warning to an additional 14 departments from midday Monday.
Nearly 35 million people live in the 49 departments concerned, including almost 4 million aged 75 or older.
The French government met on Sunday evening to discuss its heatwave response, the second emergency meeting in two days.
President Emmanuel Macron urged the public to "look out for each other", posting on X: "Let's all keep an eye on our elderly, our children and those who are isolated or vulnerable."


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