Performance of GFDL SHiELD and T-SHiELD Forecasts During Recent Hurricane Seasons

The NOAA Geophysical Fluid Dynamics Laboratory (GFDL) has developed a modeling system based on the Finite-Volume Cubed-Sphere dynamical core (FV3), called the System for High-resolution prediction on Earth-to-Local Domains (SHiELD). Two configurations of SHiELD are run in real time for tropical cyclone (TC) prediction. In addition to a global uniform 13-km configuration (SHiELD), a two-way nested T-SHiELD configuration is run that places a 3-km nest over the Atlantic Basin. This presentation will review the performance of both of these model configurations for forecasting TCs in the 2022 and 2023 hurricane seasons. Both SHiELD configurations have very strong track forecasting skill. Results will also be shown for intensity and wind radii forecasts. During the 2022 Atlantic hurricane season, T-SHiELD forecasts were run out to 7-days lead time, enabling a more complete comparison of TC genesis between the SHiELD and T-SHiELD configurations that will be shown. An evaluation of TC Quantitative Precipitation Forecasts for U.S. landfalling storms for the 2021-2023 Atlantic seasons will also be presented. SHiELD’s results will also be compared with those from operational models such as the GFS and ECMWF global models and also NOAA’s newly operational HAFS-A and HAFS-B regional hurricane models.