Abstract: Based on the data of conventional meteorological observation data, regional automatic station encryption, and ECWMF thin grid model (0.25 ° × 0.25 °) , A heavy rainstorm occurred in the eastern Qinghai Province from July 23 to July 24 ,2017 is analyzed in the paper. the result shows that the ECWMF fine-grid data like overlay area of high humidity in the middle and upper layer, the convergence area of water vapor flux divergence are good indicators for forecasting heavy rainstorm area. But for heavy rainfall and above, the single-model forecasting is small in magnitude and westward to rainfall zone, while related products of multiple models provide a better reference to forecasting, and the localized QPF objective products have valuable reference to large-scale rainstorm forecast .