SAR FV3 Based Storm-Scale Ensemble Implementation and Testing for the 2019 HWT and FFaIR Experiments

In preparation for the 2019 Hazardous Weather Testbed (HWT) Spring Forecast Experiment (SFE) and Hydrometeorology Testbed (HMT) Flash Flood and Intense Rainfall (FFaIR) experiment, the Center for Analysis and Prediction of Storms (CAPS) implemented and ran 14 ensemble forecasts of the newly developed Stand Alone Regional (SAR) FV3, at ~3 km grid spacing over CONUS. The ensemble was run daily in real-time on Stampede at the Texas Advanced Computing Center (TACC, an NSF XSEDE HPC resource) during the HWT SFE and HMT FFaIR, representing the first time that an SAR FV3-based ensemble was run. The ensemble consisted of two groups: The first group of 7 members share the same initial and boundary conditions interpolated from the operational North American Mesoscale (NAM) model analysis and forecasts; and the members differ in the model and land surface model, microphysics, planetary boundary layer, and surface layer schemes used. The other group of 7 members contain in addition initial and boundary condition perturbations derived from the operational Short-Range Ensemble Forecast (SREF) system while one of them derives its initial conditions from the operational NCEP Global Forecast System (GFS). All physics schemes used were implemented using the new Common Community Physics Package (CCPP) interface.

The implementation details of the physics schemes will be discussed. Results from the 3 March 2019 southeast US tornado event will be shown as this case was used to test the implementation of the physics schemes. Hurricane Barry and other significant cases from the HWT and FFaIR experiments were critically examined and will be discussed.