The thermometer is soaring in the Lyon metropolis. According to the reference station in Lyon-Bron and the readings from Infoclimat, the temperature reached 38.9 °C in recent hours. That's even higher than what was recorded at the same time in cities like Dubai, which are famous for their desert climate.
While 72 French departments are or will be under a red heatwave alert from Météo-France, the Rhône is an exception. This situation might lead one to believe that the heat is less intense locally. In reality, experts are urging not to underestimate the danger.
Why is the Rhône under orange alert?
The absence of a red alert doesn’t mean that the situation is risk-free. Gabriel Chantrel, a forecaster,at Météo-France reminds us that the orange alert level “is not to be taken lightly and should absolutely not be ignored” in comments shared by Le Progrès.
The activation of a red alert does not solely depend on the maximum temperatures observed. It is defined department by department with the health authorities, particularly Santé publique France, taking into account several criteria: past heat events, their consequences on the population, and the territory's adaptation level to extreme heat. The Rhône often faces heatwaves, so the alert thresholds are understandably higher than in other departments that are less accustomed to such extreme episodes.
A situation that remains under close monitoring
Even without a red alert, the next few days are expected to be particularly challenging. Météo-France indicates that these high temperatures should continue throughout the weekend, and the alert level will be reassessed daily based on changing weather conditions.
For the record, the Rhône region had already experienced a red alert during the heatwave on August 12, 2025. Generally speaking, a heatwave is characterized when temperatures reach or exceed an average of 34 °C during the day and do not drop below 20 °C at night for several consecutive days. While neighboring departments like Loire and Saône-et-Loire shift to red alert, residents of Lyon remain in orange... but one thing is for sure: with temperatures close to 39 °C, caution is more essential than ever.
Source: The Progress