This paper analyses the northward movement and activity of convective cloud clusters over the Bay of Bengal through May to June.

Hail s strength are associated with convective cloud s evolution and strength.

The first strong precipitation is caused by strengthening local convective clouds generated in the subtropical high,vapor transportation and dynamic conditions offered by strengthened easterly flow in bottom of the troposphere air promote the development of convection;New clouds in the humid air environment will be rapidly strengthened and developed.

Based on analysing 9 cases of mesoscale convective cloud cluster over clod front cloud system during 1994~2002, it was found that the origin in which the mesoscale convective cloud was outgrowth located in middle and southern parts of Guizhou province .

The mainly features of mesoscale convective cloud clusters during four heavy rainfall stages in Changjiang River Basin have been studied by using GMS TBB data of every hour on every day from June to August in 1998.

Using the daily and monthly NCEP/NCAR reanalysis data,Outgoing Longwave Radiation(OLR) data,monthly precipitation of 160 stations in China and daily precipitation of 45 stations in South China,relationships among sustained torrential rain in South China,anomalous convection over the Bay of Bengal and evolution of the western Pacific Subtropical High in June 2005 are analyzed.

Based on EOS/MODIS multi-channel remote sensing data,the characteristics of a strong convective cloud were analysed qualitatively according to a heavy rainfall in the northern of Anhui province from 30, June to 1,July in 2006.