Heatwave expected in France with peak expected on Saturday

Temperatures will rise in France in the coming days, reaching 38°C locally, in a heatwave that will peak on Saturday before a cooling down is expected on Sunday, Météo France announced on Wednesday.

Temperatures will gradually rise on Thursday, then Friday, and finally until "Saturday, which should be the peak of this episode, particularly in the West, with values ​​that will frequently be between 34 and 37 or even 38 degrees," said François Gourand, forecaster at the public establishment, during a press conference.

The night from Thursday to Friday "will itself be very hot in these western regions, with temperatures often not falling below 20 degrees in minimum temperatures" , a nocturnal phenomenon which should become even more pronounced the following night, he added.

The forecaster then expects "a cooling down on Sunday which should be quite marked" , particularly in the West, with heat which should however persist in the East of the country.

Météo France has already placed a number of departments in the West and Auvergne-Rhône-Alpes on yellow heatwave alert ("be careful") from Thursday midday, but plans to place some on orange alert ("be very careful") later in the week.

"We will raise the alert level to orange from Friday in part of the region from Poitou-Charentes to Brittany. It is still a little early to specify exactly which departments are affected," said Valérie Scavarda of Météo France.

These alert levels are established not only according to temperatures but also to the particularities of each department (for example, populations are more accustomed to high temperatures in the South) and health criteria.

This heat is caused by the blocking of a high pressure system over France, a situation sometimes referred to as an "omega blockage" because the shape of the air masses on the map resembles the Greek letter. A high-altitude depression over the Atlantic will bring up warm air masses present over the Iberian Peninsula.

The situation also affects other Western European countries: "it is already very hot in Spain at the moment" and we are "certainly expecting a fairly significant heatwave in England, particularly on Saturday," says François Gourand.

Regarding France, "these heat levels are remarkable for the month of June, but not unprecedented," says Matthieu Sorel, a climatologist at Météo France. The country has already experienced two notable heat waves in June in recent years, one in 2019 and another, earlier, in June 2022.

Metropolitan France has already warmed by at least 1.7°C compared to the pre-industrial era, before the massive burning of coal, oil and gas, and the public authorities are preparing for a warming of 4°C by the end of the century.

Global warming is making heat waves earlier and later, more frequent, longer, and more intense. "The question is not whether we will have 50 degrees, but rather when we will have 50 degrees in France," warns Matthieu Sorel.