P-27

Simulation of severe convective storms with hail occurrence by the COSMO NWP model

Zbynek Sokol, Petr Pesice (Institute of Atmospheric Physics AS CR, Prague, Czech Republic )

Severe convective events are difficult to forecast. Especially forecast of hail occurrence is a complicated task. In this contribution we will present a study dealing with nowcasting of severe convective storms accompanied by hail. We applied the COSMO NWP model with the assimilation of radar reflectivity data and with two moment microphysics. The model was integrated in two nested domains with horizontal resolutions of 2.8 and 1.1 km respectively. The precipitation forecasts were evaluated against the estimates of real precipitation obtained by merging radar-derived precipitation and rain-gauge measurements. We also evaluated forecasted development of convective storms using synthetic satellite images of Meteosat Second Generation (MSG) and compared them with real satellite MSG measurements for 8 infrared channels. Finally we compared forecasted hail affected areas l with areas where hail was indicated using algorithm based on applying several criteria to radar reflectivity and aerological measurements.