A meso-scale analysis is made with respect to the torrential rain of June 9,1979 over Kwangdong, South China. Increased observational data in the experimental region are employed in eliminating diurnal changes of pressure field and then filtering with the result of a meso-scale pressure field with 1-hr intervals. In addition,the triggering and propagating mechanism of the rain is discussed by use of a 2-layer model of the inertia-internal gravity wave.