An Overview of the 2024 NOAA Hazardous Weather Testbed Spring Forecasting Experiment

The 2024 Spring Forecasting Experiment (2024 SFE) was conducted from 29 April – 31 May by the Experimental Forecast Program (EFP) of the NOAA/Hazardous Weather Testbed (HWT), and co-led by the NWS/Storm Prediction Center (SPC) and OAR/National Severe Storms Laboratory (NSSL). Since 2023, SFEs have used a hybrid format, with both in-person and virtual participation. We have found that the hybrid format is ideal because we can engage those that cannot attend physically, while in-person participation enables invaluable science-based discussions and establishment of new collaborations. The 2024 SFE featured model contributions from NOAA Global Systems Laboratory (GSL), NOAA/NCEP Environmental Modeling Center (EMC), NOAA Geophysical Fluid Dynamics Laboratory (GFDL), NOAA/OAR National Severe Storms Laboratory (NSSL), the Global Modeling and Assimilation Office of NASA/Goddard Space Flight Center, and the National Center for Atmospheric Research. Similar to the previous year, a major emphasis was evaluating the Rapid Refresh Forecast System (RRFS) and the RRFS Ensemble Forecast System (REFS) for severe weather forecasting applications against their operational counterparts: the High-Resolution Rapid Refresh (HRRR) and High-Resolution Ensemble Forecast system (HREF), respectively. New testing and evaluation activities included an examination of global, data driven AI-based forecasting systems from GraphCast, Pangu Weather, and FourCastNet, and an expansion of evaluations involving the Model for Prediction Across Scales (MPAS), which included a REFS configuration where FV3 members were replaced by MPAS ones. Experimental forecasting activities involved generation of severe weather outlooks at Days 1-4, and short-term activities centered around NSSL’s prototype Warn-on-Forecast System. Specifically, in one of the short-term activities, a machine-learning-based product called WoFS-PHI, which uses predictors from both WoFS and the observation-based Prob-Severe system, was used to issue 0-1- and 1-2-h lead time hazard outlooks. The main goals of this talk will be to summarize SFE 2024 activities and highlight some preliminary results.