Structural Characteristics of the Clouds and Precipitation in a Low Vortex Rainstorm Process

Based on the satellite data and conventional observed data, the Structural Characteristic of the Clouds and Precipitation in a Low Vortex Rainstorm Process during June 25-26 of 2005 are analyzed. Results show that the rainstorm is associated with the meso-scale convective clouds (MCSs), the structures of which experience the evolvement such as generating, strengthening, coalescing, weakening and so on, and the lowest Black Body Temperature (TBB) of  which can be -90¿. The spatial and temporal distribution is inhomogeneous in the cumulous and stratiform mixed clouds. In the upper area of the convective clouds there is a high value area of ice crystal, below which there is more cloud water than surrounding, and the warm rain feature is remarkable. The researches on the forming conditions of rainstorm suggest that the southwest (SW) vortex supplies such beneficial conditions for it as vapor, dynamic convection and instability.