Evaluation of the Prediction Performance of Ensemble Forecast in Different Synoptic Systems

The operational ensemble forecast system for Zhejiang regional precipitation is established.The model is based on MM5 in the system.Eight different configurations of MM5 are used to produce an 8-member ensemble forecast.The forecasts in 2006 are verified in the fields of ensemble mean,probabilistic forecast and spread.The result show ensemble forecast is better than single forecast.The forecast ability of ensemble is different in continuous rain in autumn、typhoon in summer and other synoptic situations.The ensemble forecast is not good at temperature forecast,but it is good at speed forecast.