A Three-Dimensional Simulation of Supercell Convective Storm

A supercell convective storm is simulated by using a cloud-resolving model. Numerical experiments have been performed in 3D by using the same domain size, with a different spatial and temporal resolution of the model. High-resolution cloud model has been shown to represent convective processing quite well. Running the model in a high-resolution mode gives a more realistic view of the life cycle of convective storm, internal structure, and storm behavior. The storm structure and evolutionary properties are evaluated by comparing the modeled radar reflectivity to the observed radar reflectivity. The comparative analysis between physical parameters shows good agreement among both model runs and compares well with observations, especially using a fine spatial resolution. The lack of measurements of these species in the convective outflow region does not allow us to evaluate the model results with observations. A three-dimensional simulation using higher grid resolution mode exhibits interesting features which include a double vortex circulation, cell splitting, and secondary cell formation. 1. Introduction Convective clouds and storms represent one of the most important and challenging problems for forecasters. The severe local storms and deep convective clouds are characterized by the enhanced transport of heat and moisture in the upper layers, very strong self-organized flow fields, very complex microphysical transformations and stratospheric penetrations, and rapid evolution and dissipation processes. The precipitation processes are activated in very limited time interval and space, and their intensities are manifested by large natural variability. Supercell storms are perhaps the most violent of all storm types and are capable of producing damaging winds, large hail, and weak-to-violent tornadoes. They are most common during the spring across the mid-latitudes when moderate-to-strong atmospheric wind fields, vertical wind shear, and instability are present. The degree and vertical distribution of moisture, instability, lift, and especially wind shear have a profound influence on convective storm type. It is generally recognized that the environmental buoyancy and vertical wind shear have important effect on the characteristics of convective storms. Much of our understanding of the sensitivity of convective storms to these environment parameters has been derived from modeling studies that tested a variety of, but often idealized, environmental conditions. Numerical cloud models have contributed substantially to our understanding of supercell storms. A