An analysis was made of 12 weather processes with rainstorms and 9 processes without rainstorms from 21 June to 11 July 2003. The synoptic patterns and physical quantities for the two kinds of processes were compared. The composite-average physical variables for the two kinds of weather processes were calculated, and the thermal and dynamical conditions were analyzed respectively using T213 grid data at 20:00, in combination with the position of the ridge line of Subtropical High and the position of the surface front. Based on the results, a concept prediction model for the short-range heavy rainfall was designed.