PARIS, France (AFP) — A 30-year-old man died on an athletics track outside Paris on Thursday, as a new heatwave swept across much of France, forcing the cancellation of dozens of trains and the suspension of classes.

Although astronomical summer does not begin until Sunday, this is already France’s second heatwave of 2026, following an unusually hot spell in May that shattered records across half the country.

A man died on Thursday morning on an athletics track in the northern Paris suburb of Ermont, firefighters said, adding he was found in cardiac arrest and attempts to resuscitate him failed.

A fourth of the country, including Paris, was placed on orange alert, the second-highest, with authorities urging residents to be “very cautious.”

On Friday, more than half of France will be placed on orange alert.

National weather agency Meteo-France said the heatwave would be “widespread, long-lasting and intense.”

It is expected to last into next week, peaking on Sunday or Monday, when temperatures could reach up to 40C in several regions, including the French capital.

Sunday’s summer solstice, the longest day of the year, will reinforce the rise in temperatures with extended hours of sunshine.

Mayors across the country, where many school buildings remain poorly equipped to cope with extreme heat, were set to decide whether to suspend classes.

A number of schools announced adjustments to class schedules starting Thursday afternoon due to the heatwave, according to academic authorities, unions and documents reviewed by AFP.

In Paris, around 10 middle schools have already modified arrangements for Thursday and Friday.

In the town of Tours in the Loire Valley, mayor Emmanuel Denis said he would not hesitate to close its 58 teaching establishments if it became too hot.

“At 40 degrees, I’ll close the schools,” he said.

During a heatwave in June last year, around 2,200 schools were closed nationwide.

Rail operator SNCF cancelled 71 long-distance trains between Thursday and Monday to “prevent potential air-conditioning failures linked to very high temperatures”.

Some tourists complained about the lack of air conditioning in buildings in Paris, while others said they liked the city despite the scorching temperatures.

Marry Emmanuel, a US tourist from Arizona, said she was used to the heat but Paris for her was a “different kind of hot.”

“It’s very humid,” said the 70-year-old.

Scientists warn that heatwaves in Europe are becoming more frequent as a result of climate change.