It’s a true meteorological paradox observed this Tuesday: while some regions of France prepare to welcome an announced Mediterranean episode, temperatures are displaying figures worthy of a heatwave summer. In the heart of Var, the thermometer could flirt with 30°C, while just a few kilometers away in the Alpes-Maritimes, it could peak at 27°C. What explains this unexpected heat in the middle of October? Let’s analyze this phenomenon that, far from being trivial, results from several intriguing climatic factors.
This Tuesday is expected to be particularly hot, with temperatures reaching nearly 30°C in the Var and 27°C in the Alpes-Maritimes. However, this context is disrupted by the imminent arrival of a Mediterranean episode that promises to bring heavy rainfall. What mechanisms then explain this soaring mercury in the middle of October, despite the approach of this meteorological phenomenon?
Unusual heat for the season
The thermometer seems to have taken a whip above the normal seasonal average! For Saint-Cyr-sur-Mer, Météo-France forecasts a temperature of 29°C, which represents 7°C above seasonal norms. In Hyères and Toulon, the mercury also climbs to 25°C, an excess of 3°C. This heat is all the more surprising with the arrival of autumn.
On the side of the Alpes-Maritimes, the situation is equally striking: 27°C in Guillaumes, a gap of 9°C from the expected average, and 24°C in Menton. These temperatures far exceed seasonal values and suggest an Indian summer with a spicy touch!
The sources of this heat
This beautiful heat is mainly attributed to a warm southern flow coming directly from desert regions. This warm air current, laden with Saharan dust, began to sweep over Western Europe as early as last weekend. The dust from the Sahara creates a true “veil” over our skies, also giving an impressive yellowish tint to the ambient air.
These heat episodes have become increasingly frequent, with a notable increase in their intensity. For example, there were only two or three similar events per year, whereas in 2022, up to eleven could be counted. This reveals a worrying trend that can be attributed to factors such as increased drought and changes in the tracks of depressions, often closer to Africa.
Beware of the Mediterranean episode
But just as we have time to enjoy this mild weather, the forecast delivers a dramatic twist! Indeed, from Tuesday night to Wednesday, a Cévenol episode is expected to bring intense precipitation to France. This Mediterranean phenomenon is known for dropping impressive volumes of water in a very short time, often leaving territories needing caution.
The departments of Var and Alpes-Maritimes are already placed on yellow alert for storms and rain-flooding. The prefecture mentions precipitation amounts potentially reaching between 40 and 50mm in a matter of hours, accompanied by gusts of up to 70 km/h. In short, Wednesday promises to be largely wet after this summer interlude!
This contrast between the high temperatures of Tuesday and the expected downpours the next day is striking. While many will enjoy the pleasures of summer-like weather, special attention must be given to the sudden arrival of storms and torrential rains, which are expected to affect coastal areas before moving inland.
- High temperatures: 29°C expected in Saint-Cyr-sur-Mer, 27°C in Guillaumes.
- Deviation from norms: +7°C in Saint-Cyr-sur-Mer, +9°C in Guillaumes.
- Warm flow: Arrival of a southern current laden with heat.
- Saharan dust: Covering of yellow veils over the Mediterranean Sea.
- Multiplication of events: 10-11 episodes of Saharan dust in 2022.
- Increased drought: Change in depression tracks favoring dust.
- Imminent Mediterranean episode: Storms and heavy rains expected.
- Meteorological vigilance: Alerts for storms and flooding in Var and Alpes-Maritimes.
