The performances of the ECMWF experiemental ensemble TEPS and of the ARPA-SMR Limited-area Ensemble Prediction System (LEPS) have been compared during the MAP-SOP. In particular, the interest is focessed on precipitation prediction. LEPS is constructed by nesting the limited-area model LAMBO on some selected members of ECMWF TEPS: The member selection is performed trhough an ensemble size reduction.

Fiftheen cases of the MAP-SOP have been chosen has the sample on which assessing LEPS and TEPS performances. Some cases are heavy precipitation cases from MAP IOPs, while in the others only light precipitation has been recorded. Verification has been performed through a set of probabilistic indices (ROC area, Brier Skill Score, Cost-loss Analysis).

LEPS has been compared with some different configuration of ECWMF ensemble system. In all the configurations, LEPS results are the best as the prediction of heavy precipitation is concerned, for all the score measures. Some considerations on the probability associated to each ensemble member have also been carried on, trying to understand the possibility of transferring probability form the global ensemble to the limited-area one.