Mediterranean or Cévennes episode, what are we talking about?
A Mediterranean episode is characterized by intense precipitation, often stormy, in the Mediterranean region, mainly in autumn. These torrential rains are caused by the coming into contact of cold air coming from the north and hot, humid air coming from the Mediterranean Sea, which creates violent thunderstorms. In addition to the south of France, Italy, Spain and a large part of the Mediterranean region may be affected.
The Cévennes episode is a variant of the Mediterranean episodes, which more specifically affects the Cévennes. It occurs when humid air from the Mediterranean finds itself blocked by the reliefs of the Cévennes, where it condenses quickly and causes torrential rains. It can then cause severe flooding and very dangerous flash floods.
Downpours from Sunday evening to Tuesday
According to the Météo Chaîne, the models (still uncertain at this stage) predict in places between 100 mm and 150 mm of precipitation between the night of Sunday to Monday and the middle of the day Tuesday, or even 200 mm, or 200 liters of rain per meter square, in a localized manner. “These heavy rains will flood large areas, some of which have already experienced heavy rains in September. The soils are therefore already saturated and the risk of hydrological reaction will be significant,” indicate the forecasters.
