This video shows the three-dimensional structure of developing mesoscale convective cells (MCSs) simulated by the high-resolution (DX=1.5 km) UM-WRF model for a heavy rainfall case occurred over the Seoul meteropolitan area in 27th July 2011. Three modelled phases (liquid clouds, ice clouds, and total clouds) of water species were calculated, which were visualized simultaneously using the direct volume rendering (DVR) method. Wind vectors at 4 different levels (1000m, 3000m, 5000m, and 7000m) were also added to represent temporal variations of atmospheric flows. It shows that the vertically-developed MCSs can be separated in layers into liquid and ice clouds at about 5 km.