Based on Guizhou province''s forecasting routine, encrypted observation data from automatic ground stations, NCEP/FNL1°× 1°reanalysis data, and operational numerical forecasting model, the environmental field characteristics, small and medium-scale field characteristics on the ground and three numerical forecasting model tests of the torrential rain on June 29, 2020 in eastern Tongren City were analyzed. It was preliminarily analyzed that the possible causes of the torrential rain were the southeast retreat of the subtropical high, the maintenance of the northwest airflow at the upper level behind the northeast cold vortex trough, and the cold advection at the lower level Short-term and impending monitoring shows that radar echo has train effect, conjugate configuration of low-level convergence and high-level divergence, and middle-level cyclonic convergence; The forecast focus of rainstorm in eastern Tongren City under the influence of northwest airflow is preliminarily obtained.