THE STORM OF OCTOBER 21-22, 1994, OVER GREECE - OBSERVATIONS AND MODEL RESULTS

During October 21, 1994, a cold front passed over Greece. This frontal passage provoked catastrophic floods and there were many casualties. Eleven deaths were reported during this event, nine of them inside the Greater Athens Area. Significant damages occurred in transportation t elecommunication and energy supply networks, especially in the eastern part of the country. This paper reports on the simulations of the obs erved storm conducted by two numerical models: the Colorado State Univ ersity-Regional Atmospheric Modelling System (CSU-RAMS) and the eta-et a/National Meteorological Center (ETA/NMC) model. The intercomparison of results between a regional research-oriented model (RAMS) with an o perational model (ETA/NMC) permitted to explore the capabilities and l imitations of each one of them. RAMS was operated in a nonhydrostatic made using explicit microphysics and grid nesting (two nests with 40- and 10-km horizontal grid interval) and provided results which compare favorably with observations, suggesting that the model can adequately represent the mesoscale structure of the system. ETA/NMC is a hydrost atic limited-area model using parameterization of large-scale and conv ective precipitation. It was operated with 25-km horizontal resolution and it forecasted successfully the major characteristics of the syste m but failed in reproducing quantitatively the precipitation pattern a t the mesoscale.