The Hydrological Balance of the October 2000 Flood in Piedmont, Italy: Quantitative Analysis and Simulation

This paper aims to analyze in detail the flood event that occurred in October 2000 over the northwestern Italian regions and to test the capability of mesoscale model RAMS-LSPM in reproducing the main characteristics of the hydrological budget components during the event. On 13-16 October 2000, a deep, quasi-stationary trough hung over the western Mediterranean, causing extreme precipitation over northwestern Italy. Values exceeded 600 mm in four days, causing huge flooding and landslides with significant damage to houses and infrastructures. Also several lives were reported lost in the Italian regions of Piedmont and Aosta Valley. This disastrous flood was associated with heavy rainfall episodes over a relatively small area during the course of a four-day period. The intense rainfall over the Alps was enhanced by the confluence of the surface southeasterly flow and of the upper-level southerly current. This confluence was strongest over the zones where the maxima of rainfall and vertical wind velocity we...