Impact of Assimilating the Enhanced Atmospheric Motion Vectors on Hurricane Predictions with HAFS

Impact of Assimilating the Enhanced Atmospheric Motion Vectors on Hurricane Predictions with HAFS

Jing Cheng¹, Li Bi², Yonghui Weng³, Bin Liu³, Zhan Zhang⁴, Avichal Mehra⁴,Vijay Tallapragada⁴

¹Axiom at NOAA/NWS/NCEP/EMC; ²NOAA/NESDIS/OCS; ³Lynker at NOAA/NWS/NCEP/EMC; ⁴NOAA/NWS/NCEP/EMC;

(Abstract to be submitted to the AMS 36th Conference on Hurricanes and Tropical Meteorology)

Providing high temporal and spatial continuity coverage that airborne observations are otherwise lacking of, the enhanced atmospheric motion vectors (AMVs) have potential to benefit model forecasts of tropical cyclone track and intensity. Recent studies have shown neutral to positive impact of assimilating enhanced AMVs on hurricane predictions in multiple aspects with numerical model systems such as HWRF model. With the operational implementation of Hurricane Analysis and Forecast System version 1 (HAFSv1) in time for the 2023 hurricane season, the effect of assimilating enhanced AMVs in HAFS is worth examining. Experiments with different configurations with enhanced AMV data assimilation have been designed and conducted to help to understand the impact of ingesting the data using 4DEnVAR in HAFS. Results will be compared with operational HAFSv1 in which enhanced AMVs were not assimilated in the 2023 hurricane season. Preliminary results show neutral impacts on overall track and intensity forecasts, and positive impacts on forecasting the rapid intensify (RI) and rapid weakening (RW) stages in the intensity forecast of Hurricane Lee. This information will be used to set up enhanced AMVs DA configuration in HAFSv2.