Abstract:
Diagnostic analysis and numerical simulation have been performed for a heavy rainstorm in July,20-21,1989 in the middle western part of the Inner Monglia. The results show that South Asia high causes a strong divergence field in the upper layer of troposphere in this re-gion,the short wave trough from west makes a shear line move northword,warm moisture air and cold dry air suddenly meet each other which produces the unstable wave, and the relationship between the rainfall position and the convergence line is close, the model experiment indicates that dynamic and thermal forcing of topography is one of main reasons for the convergence of the surface wind field to form. The difference caused by the orographic effect and the intensity of the convergence line is significant.
