Considering the impact of initial matching，two groups of numerical experiments （S1 and S2） are made.The predictability of extraseasonal shortterm climate during summer is examined by the statistic crossvalidation method.The results are based on the ensembles of JJA simulation carried out with the BCC Atmospheric General Circulation Model （BCC_AGCM201） developed in the National Climate Center for the years of 1980 to 2006. It is shown that the capability of the model in predicting the seasonalscale atmospheric general circulation in the middle and low latitudes is better than that in high latitude. In general， the results also indicate that the integrated prediction agrees quite well with the observed largescale patterns of rainfall distribution. The effect of initial matching is distinct in the experiment S1 compared with that in S2， especially in the Jianghuai region and Southern China.