The Mediterranean basin and, in particular the Alpine region, was affected by some intense precipitation events during recent years. The complex orography surrounding the region and the presence of a relatively warm sea like the Mediterranean make this region very difficult to study from the point of view of the features of the atmospheric flow. Some of these events were selected inside an International Project called MAP (Mesoscale Alpine Program) and are object of intensive study in order to go into the knowledge of aspects which are not fully understood or not adequately represented in the atmospheric models. A series of simulations of one of these events events was analyzed in order to point out the main forcing which played an important role in the spatial and temporal determination of the episode and in the intensity of precipitation.