From Sunday to Wednesday, a disturbance will cross France, between central Aquitaine and the west of the Massif Central, as far as the Alps. “Falling on soils saturated with humidity, these new heavy rains will cause significant risks of flooding and floods,” warns the Weather channel on its networks. Thus, the departments of Isère, Savoie and Haute-Savoie were placed on orange “rain flood” alert at the end of the weekend, at 10 p.m.
Over the next 72 hours, the cumulative rainfall is expected to be significant again: “We expect locally between 150 and 200 mm in the north of the Alps, the equivalent of a month and a half of rain”, writes the weather channel.
The prefect of Isère calls not to take any risks
“This episode, accompanied by the melting of part of the snow cover, is likely to cause a reaction in watercourses with mudslides and landslides,” said the prefect of Isère in a press release. “On Sunday, the water height at Grenoble Bastille was around 0m80, i.e. a flow rate of around 360 m³/s,” he added. The flow threshold of 500 m3/s, or a scale height of 1.50 m, could probably be exceeded tomorrow Monday evening at the end of the night. The upward trend in this flow will in all probability continue. »
Thus, several roads are and will be closed to vehicle, cyclist and pedestrian traffic, particularly in the municipalities of Grenoble Alpes Métropole and La Tronche. “The prefect calls on everyone to follow the recommendations and not take any risks in view of this new rainy episode,” he concludes.