Precipitation Particularity of Beijing Area and Its Forecast Method

Abstract:

Two special weather events over Beijing are simulated,and a series of sensitivity experiments carried out using a nested grid version of PSU/NCAR’s mesoscale model(MM5)with a fine mesh grid size of 15km.It is shown that these two events occurred in different synoptic scale environments;the MM5 model reproduces successfully the development of the two weather processes and their relevant mesoscale systems;latent heat release acts a vital role in the development of the weather-side waves process;landuse plays an important role in the development of the lee waves weather process;responses to topographic forcing in the two cases are rather sensitive;and the store and transportation of the low-level potentially unstable energy over Beijing are the crucial conditions for the formation and intensification of convection.

Key words:torrential rain;mesoscale system;numerical simulation;physical mechanism