Extended Abstract

National Meteorological Center (NMC) of CMA as no ra in, moderate rain and heavyrain for the threat score, bias score and the brier score assessment, but all intensitieswere taken into consideration with the percentile precipitation.According to the results of threat score and bias score (Fig.1 and Fig.2), comparewith the EC, the MPS h as an equal or sli ghtly better performance, meanwhile muchbetter than CMA and NCEP. Maybe the number of ensemble members is the key toexplain the MPS inclined to EC. What must be pointed out is that the little rain forecastof CMA gives the best threat scores with the lead time less than 6 days. But the falsealarm rate o f CMA is also higher than the other s with all 10 -day’ little ra in forecast.With the result of the thr eat score and bias scor e of CMA for the moder ate rain andheavy rain, the CMA have a good performance on the little rain forecast at the price ofthe poor capacity on the heavy precipitation forecast.Fig. 1 Threat Scores of ensemble mean, CMA (black line with rectangles), EC (reddashed-circle line), NCEP (brown dotted-triangle line), and MPS (blue dashed-star line).(a)No Rain, (b) Little Rain (c) Moderate Rain (d) Heavy RainFig. 2 Bias Scores of t he ensemble mean, CMA (black line with rectangles), EC(red dashe d-circle line), NCEP (b rown dotted -triangle lin e), and MPS (bluedashed-star line). (a)No Rain, (b) Little Rain (c) Moderate Rain (d) Heavy Rain-507-