Sensitivity Analysis of the Role of Model Physics on Severe Weather Diagnostics within Tornadic Tropical Cyclone Environments

Andrew Mercer, Mississippi State University

Usage Details

Tornadogenesis within tropical cyclones is a poorly understood process, primarily owing to the difficulty in isolating the tornado environment within the larger tropical cyclone environment. There is general knowledge that the right front quadrant seems to be most favorable for tornado formation, but recent work has revealed that common severe weather diagnostics have limited capability in predicting tornado formation within the tropical cyclone environment.

The purpose of this project will be to assess the importance of numerical weather simulation model physics in simulating the tornado environment for previous major landfalling US hurricanes. In particular, the role of certain multiple model physics configurations for boundary layer physics, cumulus physics, and cloud microphysics will be assessed via sensitivity analysis for five major landfalling hurricanes. Severe weather diagnostics for the resulting simulations will be formulated and the role of their magnitudes and spatial configurations will be diagnosed based on the selected model physics configuration. In total, 24 different model physics combinations (two cumulus parameterizations, three boundary parameterizations, and four microphysics parameterizations) will be tested for five major landfalling hurricanes that produced tornadoes on the US mainland. Simulations will be completed using the Weather and Research Forecasting model (a total of 120 simulations over the 5 cases, 24 simulations per case).