In order to improve the level of operational strong convective nowcasting, the quantitative assessment software is established. The methods for assessing thunderstorms, local torrential rainfall, and gale, and the software development, are introduced. The assessments of severe rainfall and gale are conducted in a graded mode with intensive observation data, and that of lightning is based on the data of ground lightning strokes from the ADTD system. The assessment results in 2011 show that the method is reasonable and feasible in operation. There are also some problems because it is simple, preliminary, and experimental.