Severe flooding over central and southern Greece associated with pre-cold frontal orographic lifting

Abstract

An extreme rainfall event, associated with a cold front, which occurred on 11-12 January 1997 over Greece is investigated through observational analysis and numerical simulations. The analysed storm system produced large amounts of rainfall, with devastating impacts over central and southern Greece, where at some sites 24-hour accumulated precipitation exceeded 300 mm. The model analysis was performed with the three-dimensional non-hydrostatic Colorado State University Regional Atmospheric Modeling System. The model results caught the larger-scale features present in the observational analyses while developing more realistic finer-scale features. Sensitivity tests are also performed in order to investigate the role of the topography of the Greek peninsula on the enhancement of convection. Indeed, the orientation of the flow was optimal for advection of moist air with a maximized fetch over the sea, and at an angle of impact optimum for orographic lifting ahead of the main topographic axes of continental Greece