Mesoscale Convective Complexes over the Southern China Mainland

Ten mesoscale convective complexes (MCCs) over the southern China mainland during late spring and early summer were computed and analysed using GMS S-VISSR data and conventional data. The results show that they are nocturnal and initiate at slope or near slope bottom of plateau or mountains leeward, and develop at the special favorable area where several synoptic systems from low- and mid–latitude are merging or interacting with each other. They move toward east by south and tend to the mean flow in 700~500 hPa layer. The cold-cloud-shield is about 1.4×105km2, which is smaller than that of MCC in the America ((2~3)×105km2), but it lasts for about 12 hours while the American shield about 10 hours. The eccentricity of cloud shape (≥0.6) is slightly smaller than that in the America (≥0.7). The minimum temperature of cloud top is generally colder than －86℃, which appears 4~6 hours earlier than the time of the maximum cold-cloud-shield extent