convective rainfall
1.The qualitative identification methods of Doppler radar velocity PPI pictures are introduced. The related image features of convective rainfall clouds are analyzed: ① the zero-velocity lines in the wind field related to large-scale convergence or divergence in combination with cold or warm advection;
2.The analyses suggest that the first and second categories of rainstorms are associated commonly with the strong inertial instability in the upper troposphere, as well as respectively with symmetry and convective instabilities, and their rainfall is large; and the third and fourth categories generally produce stable precipitation with a small rainfall, and their upper tropospheres are usually inertially stable.
3.The rainfall process was caused by a mesoscale convective system(MCS) and a vortex associated with its development.
4.By mesoanalysis of a precipitation that occurred in the middle reaches of the Changjiang River, 8th Jul. in 2003, the formation and development of the event, its relation with the meso-microscale system are studied, it is emphasized that the low-level jet would cause favorable thermodynamic, moisture and dynamic conditions for the heavy rainfall in the middle reaches of the Changjiang River and that the mesoscale vortex formed in the left of the low-level jet would stimulate strong convective clouds and cause the heavy rain.
