9521759 Fiedler Tornadoes are recognized as one of the most violent, localized weather phenomena. Much progress has been made over the last several years in understanding both the structure of tornadic thunderstorms and the dynamics of tornado vortices. There still, however, are unanswered questions as to the dynamics of substructures contained within a tornadic vortex and the relationship between the tornado s characteristics and the local environment. In this research, tornadoes will be simulated using a very advanced three-dimensional numerical model. The model to be used is capable of continuous dynamic grid adaptation and is ideally suited for resolving moving entities requiring enhanced resolution in a relatively small region of the modeled domain. The project goal is to determine how the maximum wind speed in a tornado is related to environmental conditions, such as convective available potential energy and radial inflow at the base of the tornado. The planned numerical simulations also will allow a study of asymmetric vortex breakdown, instabilities, turbulent transport and multiple vortices. The results of this research should lead to a better understanding of the especially violent substructures of tornadoes (e.g. satellite vortices) and eventually enhance the ability to predict such phenomena. ***
