According to the continuous heavy rainfall events in the ChangjiangHuaihe River valley in summer 2003 and in South China in summer 1998,the ICTP Regional Climate Model (RegCM3) is used to simulate the effect of the heating anomalies over the ChangjiangHuaihe River valley,South China and the Bay of Bengal on the shortterm E/W and N/S positions of the Western Pacific Subtropical High (WPSH) during the heavy rainfall.The simulations confirm that the shortterm position variations of WPSH are closely associated with the atmospheric heating fields and their patterns.The heat source over the Bay of Bengal to far west of WPSH may induce an anomalous westward extension of WPSH during the continuous heavy rainfall.During the torrential rain in South China,the configuration of heating fields over South China and the Bay of Bengal may lead to a shortterm eastward withdrawal of WPSH during its seasonal westward extension.During the torrential rain in ChangjiangHuaihe River valley,the heat sources over ChangjiangHuaihe River valley and the Bay of Bengal may induce an anomalous westward extension of WPSH.But the effect is not evident in the simulation of the N/S position variation of WPSH,which can not approve that the WPSHs N/S position variation can be hindered individually by the heating source over South China or ChangjiangHuaihe River valley.