Future Northeastward Shift of Extratropical Transition of Tropical Cyclones Over the North Atlantic in Downscaling Projections

Abstract Tropical cyclones (TCs) often undergo extratropical transition (ET) at the midlatitudes, becoming post‐tropical cyclones (PTCs). We combine a logistic regression PTC identification model with synthetic TC tracks and intensities from the Columbia HAZard model (CHAZ) to project future ET completion over the North Atlantic (NA). Projections are based on downscaled outputs from 12 Coupled Model Intercomparison Project Phase 6 (CMIP6) models under three shared socioeconomic pathways (SSPs): SSP2‐4.5, SSP3‐7.0, and SSP5‐8.5. Future changes in PTC numbers largely follow projected TC frequency, while the ET fraction remains nearly unchanged. Despite this stability, the preferred ET completion region shifts northeastward. This shift likely results from weaker vertical wind shear, larger potential intensity, slower overall translation speed at the midlatitudes, and more northward TC genesis. Although storms move more slowly overall, an enhanced eastward storm‐motion component favors the northeastward shift, whereas a weaker northward component partially offsets the displacement.