ABSTRACT Tropical cyclone precipitation (TCP) impacts are difficult to predict due to rapid structural changes during landfall. This study applies a shape metric methodology to analyze TCP evolution across the North Indian (NI), Western Pacific (WP), and North Atlantic (NA) basins using the Integrated Multisatellite Retrievals for GPM (IMERG) and IBTrACS datasets from 2014 to 2024. TCP characteristics are evaluated at three stages: pre‐landfall, landfall, and post‐landfall, using six spatial metrics (area, closure, solidity, fragmentation, dispersion, and elongation) and three rain rate thresholds (2, 5, and 10 mm hr. −1 ). The Kruskal‐Wallis test is used to identify significant changes in precipitation structures across the landfall stages. Results show that TCP becomes progressively less compact and more dispersed after landfall, with closure decreasing and dispersion increasing, indicating a more exposed TC center. Basin‐specific differences were observed: the WP consistently exhibits the largest precipitation area and fragmentation and lowest solidity, while the NA shows the highest solidity and lowest fragmentation, and the NI displays the greatest elongation, potentially associated with monsoonal influences. Maximum precipitation rates decline significantly after landfall across all basins, with the steepest decrease in NI. There are also distinct directional pattern difference among basins. This study demonstrates how shape metrics can effectively capture basin‐specific changes in TCP structure during landfall. The findings can improve understanding of rainfall evolution and support enhanced flood risk mitigation in coastal regions.
Sauda et al. (Fri,) studied this question.