Relative accuracy of HWRF reanalysis and a parametric wind model during the landfall of Hurricane Florence and the impacts on storm surge simulations

Prediction and reanalysis of storm surge rely on wind pressure fields from either parametric tropical cyclone models or numerical weather model reanalysis, both are subject to large errors during landfall. This study assesses two sets wind/pressure for Hurricane Florence that made landfall along the Carolinas in September 2018 appraises impacts differential structural suites modeled predictive accuracy driven thereby. The first set was produced using Holland 2010 (H10), second is Weather Research Forecasting (HWRF) created by NWS National Centers Environmental (NCEP). Each validated a surface data collected at public commercial platforms then used as input forcing 2-D coastal hydrodynamic (Delft3D Flexible Mesh) produce Carolina coasts major sounds. Major findings include following. First, HWRF overall more accurate than those based H10 periphery storm, though they exhibit limitations resolving high speeds near center. Second, applying best track yields an erroneously spike speed 15th when reduced depression. Third, progressively negative bias after landfall, likely due deficiencies representing boundary layer processes, lack assimilation product compensating these deficiencies. Fourth, forcings Delft3D peak surges simulations, there severe underestimation shoreline close simulations biased low H10, even over several locations clearly overpredicts speeds. contrast highlights importance further away center order accurately reproduce associated flooding.