Abstract:A typical rainstorm process in Haihe River Basin during 22nd 24th July 2005 is synthetically studied with numerical model, conventional observations, multiple physical indexes, satellite data and radar data etc. To be summarized, the findings from the analysis are as follows: 1) the whole process was co deve loped by an upper trough, the warm moist airflow on the edge of subtropical hig h and the low pressure cloud system triggered by Typhoon Haitang during its col lapse phase. 2) The whole process is caused by some intensely developing meso and micro scale convective cloud clusters which are triggered in the warm area by the updraft flow in front of cold air mass under some favor conditions such as high temperature and moisture and stratified instability. 3) The numerical mo deling forecasting has some indicative sense on the time and location of the hea vy rainfall and the cold advection in the middle of troposphere that intruded in toHaihe River Basin. Compared to the model developed by Germany, Japanese model a nd T213 model have shown predominance on the location forecasting of the heavy r ainfall in Haihe River Basin. However, the quantitative precipitation forecastin g from German model is most close to the observations. As a whole, these three m odels all have poor accuracy in the location of the west edge of the subtropical high. This fact is thought to be one of the reasons causing the forecasting err or in the temporal and spatial distribution of the heavy rainfall in Haihe River Basin.