Tropical cyclone flow structure in the presence of elevated terrain

This study investigates the consequences associated with downslope flow produced by a tropical cyclone interacting with elevated terrain. Particular examples include altering the storm track through the production of potential vorticity, changing the storm's convective structure through the ingestion of dried downslope air, and the enhancement or weakening of surface winds due to terrain effects. To investigate these potential processes, a series of idealized numerical simulations were performed with the tropical cyclone version of the Naval Research Laboratory's Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS-TC©). Axisymmetric Rankine vortices of varying intensity were placed in a uniform mean flow which directed the storm toward an idealized sinusoid island with a major axis oriented normal to the flow. The offset between the center of the storm and the island centerline was varied incrementally between 0 and 0.75 times the island width in either direction. Fields of pressure, wind vectors, simulated radar reflectivity, and potential vorticity are presented with the focus of analysis on the storm's track and convective structure and the leeside winds for each storm track.