Virtual reality is the most important character of 3D GIS

whose essence is the integration of visualization technology and GIS databases to meet the needs of a variety of applications such as agricultureor

disaster prediction. In this study

based on the environmental data and meteorological data of a GIS database

meteorological data can be visualized in near real-time

through the simulation of rain and snow effects. In this paper

we use particle systems to reach better real-time effect with lower memory consumption through endowing every particle with a large area texture. Thus

the number of particles reduces to 10% of common particle system and rendering speed rises over 10 times. GPU coding is used to accelerate 3D rendering of the ground effect of the rain. The prototype system can accept the settings of particle texture and rainfall or snowfall intensity by users. To satisfy practical applications

we propose a self-adaptive strategy based on meteoro-logical data.