Performance of an Experimental HAFS-B Configuration During the 2024 Hurricane Season

The Hurricane Analysis and Forecast System (HAFS) is a newly-operational hurricane model developed in NOAA as part of the Unified Forecast System (UFS). There are currently two operational versions of HAFS: HAFS-A and HAFS-B. In order to maintain diversity between the two versions of HAFS, and improve the forecast skill, we explore using a different convective scheme in HAFS-B, the scale-aware Tiedtke scheme. The experimental configuration includes modifications to the scale-awareness calculations and entrainment coefficients to improve the representation of TC structure and intensity. The experimental configuration of HAFS-B also includes modifications to the coupled ocean model and initialization. The experimental configuration, known as HAFSV2.0.1B (or H2XB) was run in near-real-time during the 2024 Atlantic and East Pacific hurricane seasons. We evaluate the performance of the model based on skill of track, intensity, and TC structure relative to operational HAFS-B, and also examine details of the model performance during high-impact cases. These evaluations help us to further refine model upgrades prior to operational implementation.