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In this work, the results obtained with the analysis of 3 years of data concerning the occurrence of local severe weather events (LSWE) in the plain of Friuli Venezia Giulia (FVG) are presented. These data are essentially collected by volunteers who personally observed the development of these phenomena or at least the damages produced by them. These data show that local severe weather events are much more frequent than previously expected just because of the occasional reports; moreover, they appear to be mainly associated to the approaching of a cold front over the Friuli region. The spatial distribution of these phenomena is not uniform, even if the study area is relatively small, but it is likely dependent from the interactions between synoptic perturbations and orography. [Copyright &y& Elsevier]

Hail is quite common on the plain of Friuli Venezia Giulia (FVG), for this reason a network of polystyrene hailpads was established in 1988. This network remains active today monitoring hail frequency and aspect. We use the data of this network to define the hail climatology for Friuli Venezia Giulia, in particular, its spatial and temporal frequency, and to give a physical interpretation of the observed behavior. The main features that emerge from the analysis are that, even if hail is a local phenomenon, its climatology can be interpreted only by accounting for the mesoscale mechanisms triggered by the interplay between synoptic perturbations and the complex orography of Friuli Venezia Giulia. The analysis also reveals the importance of the lower level (say below 1500 m) water vapor amount for the occurrence of hail. The yearly frequency of hail days in Friuli was also compared with that of other regions and Countries, as well as with the time series of the North Atlantic Oscillation index. The results reveal some significant, even if weak, connections. [Copyright &y& Elsevier]