The Research HWRF system: Looking beyond the 10-m Wind Speed for Improved Storm Predictions

More than 80-90% of the deaths due to Tropical Cyclones (TCs) are caused by fresh water flooding and storm surge. Although the operational HWRF system is starting to show some exceptional skills in intensity forecasting, TCs such as Irene (2011), Isaac (2012) and Sandy (2012) have all illustrated the importance of providing more accurate structure (size) and rainfall predictions. Also, the current operational HWRF configuration is storm centric and single nested, not ideal for representing multi-scale interactions or for post landfall applications, and is greatly limited in extending forecast lead times beyond 5 days. Key for improving storm-storm interactions, critical for improving RI predictions and near land fall (size) and post-landfall applications (rainfall), and for extending forecast lead times beyond 5 days lies in the creation of a basin scale model (eventually covering the entire globe) with multiple moving nests at 1-3 km resolution covering all the storms in the basin. Based on the 2013 HWRF system that includes the operational initialization scheme and recent upgrades to physics, the Hurricane Research Division (HRD) of the Atlantic Oceanographic and Meteorological Laboratory (AOML) with its partners at Environmental Modeling Center (EMC), National Centers for Environmental predictions (NCEP) have created a basin scale HWRF system that can operate with multiple moving nests spanning at resolution down to 3 km. Supported by NOAAs Hurricane Forecast Improvement Project (HFIP), this version of the HWRF was run for the 2013 hurricane season and also in a retrospective mode for the 2011-2012 seasons. We are starting to see some improved performances in tracks and structure predictions with the basin scale HWRF. An overview of this system along with the advantages of transitioning to such a system into operations will be provided. We will also show some improved performance from Hurricane Sandy, explain how this version improves forecast and emphasize the need for looking beyond the 10-m wind for post land fall predictions. This version of the HWRF will be available to the community for research.