Development and Evaluation of the Second Hurricane Nature Run Using the Joint OSSE Nature Run and the WRF Model

A "nature run" is a high-quality simulation of a phenomena of interest which is used to provide data to be assimilated into a forecast model, for the purpose of evaluating the forecast model, its data assimilation scheme, and the potential utility of new types of observation. Previously, a hurricane nature run was produced by downscaling the WRF model inside the Joint OSSE Nature run that was produced using the ECMWF global model with T511 resolution. The first nature run depicts the complete life cycle of a tropical cyclone, from tropical wave to major hurricane to recurvature into the North Atlantic. A second nature run has been generated that produces a very different evolution, passing over the Greater Antilles as a tropical wave and a depression and then rapidly intensifying as it travels from near Havana, Cuba, to landfall over Tampa, Florida. This simulation depicts significant effects of land and topography on a tropical cyclone with 1-km resolution model output saved every 5 minutes over the 8 day simulation. The realism of the simulation as well as other applications of the model output data set will be discussed.