Abstract: The one-dimensional time-independent cumulus model has been used to compute the 07h sounding data from Beijing in June 1964-1975 and in July 1964-1976.The results have been used to analyse the real hail data of Yanqing in order to obtain the forecast indices. The accuracy rate of hail forecast is 71% for past records of 403 days. Besides, we have computed the 13h sounding data and discuss the effect of mesoscale lifting. They are useful to improve the accuracy rate of hail forecast.