In this work, we present an overview of new CM1 simulations conducted on the Blue Waters supercomputer, initialized with the same environmental conditions, but with different model parameter choices, at different resolutions, and with a newer version of the CM1 model in order to explore simulation sensitivity. In a free-slip simulation run at 20 meter isotropic grid spacing, a violent tornado forms, initially with a single-celled structure, then transitioning into a two-celled tornado before becoming a wide, multiple-vortex tornado. A 20-meter simulation incorporating surface friction reveals notably different storm structure at low levels compared to a free-slip simulation and produces a shorter-lived, less intense tornado. These and other simulations utilizing an updated version of the CM1 model will be presented and the salient characteristics of the simulations will be compared and contrasted.
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