A precipitation process caused by a cold front and a southwest vortex occurred on April 14,2000 in Henan province.The cloud system distributed unevenly.There was a band-shaped gap between two clouds and two band-echoes appearing on radar echo images.Non-uniformity also appeared inside the cloud bands and the cloud system was layered vertically.The microphysical characteristics of the precipitable cloud system were analyzed.The areas with plenty of supercooled liquid water(SLW)were determined according to the PMS indices.Distributing characteristics of the areas with plenty of SLW were analyzed by using satellite and radar data.Evidence of convective unstability of the precipitable cloud system was also observed.