Impact of stochastic model physics on hurricane intensity change forecasts

This study evaluates the impact of stochastic model physics on hurricane intensity change forecast using the operational Hurricane Weather and Research Forecast (HWRF) ensemble system. We focus on perturbing parameters related to sub-grid scale model physics. These parameters include the drag coefficient, exchange coefficient for enthalpy transfer, vertical and horizontal eddy diffusivity, etc. We aim to identify parameters that help improve the spread of the intensity change forecasts. We also aim to identify key physical processes, especially those in the boundary layer, that are associated with hurricane rapid intensification (RI) through composite analysis of the ensemble forecasts.