THE MODELING STUDY OF DOWNBURST^*

Downburst is a very dangerous weather phenomenon for aeroplane taking off or landing. In order to understand the initial formation and evolution of downburst and to study the effects of atmospheric environment condition and the microstructure of cloud-precipitation particles on the downburst development processes, we have designed and carried out a modeling scheme by making use of our own non-hydrostatic compressible mesoscale-γ model including necessary cloud-precipitation processes. The initial conditions of temperature, humidity and wind are from an observation case in which the downburst occurred. The results of computations demonstrate the evolution of downburst and show the variation of various environmental and microphysical parameters. Some of the mechanisms about the downburst occurrence have been obtained. Computation results may help airport forecasters to determine the occurrence of downburst better.