Abstract:The precipitation of a convective-stratiform mixed cloud in Zhangjiakou during 18—19 April 2009 is simulated using the mesoscale numerical model WRF-ARW(V3.2) and comparatively analyzed with the observation data in different scales.Results show that the west wind trough at 700 hPa and the low vortex at 850 hPa are the main weather systems responsible for convective-stratiform mixed cloud.The warm wet air from the southern and the low vortex from northwest Inner Mongolia are main water vapor suppliers, which converge in Zhangjiakou region and thus are conducive to cloud system development and precipitation formation.The cloud system shows a NE-SW banded distribution, which is 1000 km long and 300 km wide, and has lots of cloud water centers, which are about tens of kilometers.The cloud system has the echo characteristics of typical convective-stratiform mixed cloud precipitation, such as columnar echo of cumulus cloud embedded in uniform echo layer.The cross-section of radar echo shows that the cloud water content is heterogeneous either horizontally or vertically.The centers of rainwater are corresponding with the centers of graupel and snow in the upper layer, with horizontal range of 10—20 km.