Saint-Etienne sits near the Alps or the Rhone valley in east-central France, where mountainous terrain intensifies rainfall and can turn a heavy storm into a fast-rising mountain stream within a very short time.
In the hills southwest of Lyon, the city’s terrain can channel heavy convective rain into fast-rising streams. The combination of steep terrain and intense convective storms makes this one of the more flash-flood-prone parts of France, and radar tracking of individual storm cells is especially useful here. Learn more: Flash Flood Warning Signs on Radar · Open the full Rain Map