Non-geostrophic WetQ-vector Analysis and Application of Heavy Precipitation in Winter in Yunnan
A diagnosis of a heavy rainfall from Jan.5 to Jan.6,2003 is made with the Non geostrophic WetQ-vector(Q*) theory. The results show that the transverse shear line over the Qingzang Plateau and the trough eastward at the 500hPa, southwesterly jet at the 700hPa, and heavy cold front on the surface are the important influencing systems. The region of heavy rainfall has a good relation withQ*vergence center or line. The changes ofQ*frontogenesis function at the 800hPa reflect the intensity of front,and the region magnitudes ofQ* frontogenesis function could be used to locate the snowfall area.Q*divergence at the 700hPa has positive correlation with the development and the intensity of heavy preciptitation in winter in Yunnan.