twenty-eight departments on orange alert, the peak in temperatures expected between Monday and Wednesday

A heat stroke of exceptional intensity at the end of summer hit a large part of France on Saturday August 19, when French roads look very busy. No less than twenty-eight departments have been placed in vigilance orange heat wave by Météo-France for Saturday, forming a vast diagonal going from the Gers to the Haut-Rhin and up to Savoie.

The temperature will be particularly high in Montélimar (38°C), Lyon, Avignon and Albi (37°C), Toulouse, Carcassonne and Annecy (36°C) and Mâcon, Montluçon and Agen (35°C). This episode, the hottest of the summer of 2023, is due to the installation above the country of a heat dome, that is to say “a vast anticyclonic zone at any level of the atmosphere which traps the already hot air and heats it up by compression, a bit like a bicycle pump”explains Météo-France.

” Yesterday [vendredi]the national thermal indicator reached 25.7°C, so it is the hottest day of the summer of 2023 but also of the year”according to an official of the institution. “We have exceeded the value of July 8, 2023”, which was 25.1°C. Faced with this heat stroke of exceptional intensity, Elisabeth Borne called for caution on X (formerly Twitter) after bringing together an interministerial crisis unit on Thursday.

Heat exacerbates dryness

“At work, on the way home or on vacation, let’s all be vigilant: make sure you stay hydrated and watch out for vulnerable people”, she urged. Especially since Saturday is also classified as red by Bison Futé in the direction of returns and orange in the direction of departures throughout the territory, in this eighth weekend of summer. Around 10:40 a.m., its services already counted some 480 kilometers of traffic jams, the A7 sun highway being by far the most congested.

While the peak of the heat wave is expected “between Monday and Wednesday” before a possible drop in temperatures on Thursday, the authorities have multiplied health prevention messages, particularly in large cities, which are undergoing the formation of numerous heat islands, first affecting the most precarious populations, and have put in place measures to hear from fragile and isolated people.

In addition to the daily difficulties, the high temperatures exacerbate the problems of drought, while seventy-eight departments were concerned in mid-August by water restrictions, including forty in a crisis situation, corresponding to the highest level of alert, according to the French Office for Biodiversity (OFB). Several departments of Centre-Est, Loire, Haute-Loire, Savoie, Ardèche or Drôme announced new restrictions this week.