System Sciences

Abstract. Forecast verification is a long-standing issue of the whole meteorologists ’ community. A common definition of a truly satisfying prediction skill has not been achieved so far. Even the definition of “event”, due to its spatio-temporal discontinuity, is highly affected by uncertainty. Moreover, decision-making demands numerical weather prediction modellers to provide information about the “in-ner ” uncertainty, i.e. the degree of uncertainty related to the choice of a specific setting of the model (microphysics, tur-bulence scheme, convective closure, etc.). Most European Mediterranean countries, due to dense de-velopment, steep coastal orography and short hydrological response time of the drainage basins, have to deal very fre-quently with flash floods and sudden shallow land sliding im-pacting on urban areas. Civil protection organizations are i