Weather visualization has traditionally been restricted to surface models and 2-D representations. We present a visually accurate method for rendering volumetric multi-field weather data that includes cloud water, ice, rain, snow, and graupel hydrometeors. This representation better communicates the complex 3-D nature of weather, by rendering it according to physically based lighting and scattering characteristics of hydrometeor particles. The rendering system works with the new Weather Research and Forecasting (WRF) NWP model as well as cumulus cloud dynamics models. We have successfully rendered a simulated WRF supercell storm at interactive rates with high visual accuracy. Therefore, improved NWP model evalulation can be achieved through this new visually accurate system, and the software has potential uses in, not only weather forecasting and research, but in the education of weather spotters and the general public.