25ARAM Comparing HRRR and RRFS in Predicting Convective Systems over the Eastern CONUS in JJA 2023 and 2024

In this study, we provide a comparison of the operational High-Resolution Rapid Refresh (HRRR), and the current experimental version of its successor, the Rapid Refresh Forecast System (RRFS) model, at predicting convection during the summers of 2023 and 2024, including how improvements to RRFS have affected forecast skill between the two summers. In 2023, we assessed both models' performance in predicting the storm area and count of 28 individual widespread convective events at hourly temporal resolution, while in 2024 we expand this to assessing the convective forecasts for the entirety of both JJA convective seasons at 15-minute temporal resolution. Preliminary results from June and July 2024 show a lessening of the strong positive convective area bias seen in RRFS in JJA 2023, bringing it closer to the skill of the currently-frozen HRRR model. We also plan to summarize model performances based on Air Traffic Control Center (ARTCC) regions.

This research is in response to requirements and funding by the Federal Aviation Administration (FAA). The views expressed are those of the authors and do not necessarily represent the official policy or position of the FAA.