In an era marked by intensifying weather extremes, a groundbreaking study uncovers a significant rise in the precipitation rates of tropical cyclones (TCs) as they approach landfall globally. By meticulously analyzing over four decades of data spanning from 1980 to 2020, scientists reveal an alarming increase in rainfall intensity associated with these destructive storms, particularly in the crucial 60-hour window leading up to landfall. This discovery sheds new light on the evolving nature of tropical cyclones and poses urgent challenges for disaster preparedness and mitigation worldwide.
The research harnesses an unprecedented fusion of multiple high-resolution datasets to trace the precipitation patterns of tropical cyclones globally. Core to the analysis is the International Best Track Archive for Climate Stewardship (IBTrACS), which offers comprehensive, 3-hourly records of tropical cyclone positions, wind speeds, and critical landfall indicators. Complementing this are advances in precipitation measurement, notably the Multi-Source Weighted-Ensemble Precipitation (MSWEP) database, integrating rain gauge observations, satellite data, and atmospheric model outputs to deliver reliable rainfall estimates at a fine spatial resolution of 0.1° latitude and longitude.
The study underscores the imperative of focusing on landfalling tropical cyclones, defining these events as those achieving a lifetime maximum intensity of at least 35 knots and sustaining a lifespan of over 60 hours before crossing a coastline. This meticulous selection ensures that the samples studied genuinely represent significant and typical storm events with potential for impactful weather and societal consequences. In total, 1,468 such events were identified and categorized based on geographical regions, hemispheric location, ocean basins, latitudinal belts, and the Saffir–Simpson Hurricane Wind Scale, providing a broad framework for interpretation.
Precipitation linked directly to storm systems was pinpointed by analyzing rainfall within a 500 km radius surrounding the storm center at 3-hourly intervals. Such granularity allowed differentiation between the inner core rainfall (within 0-200 km) and the outer rainbands (between 200-500 km) of each cyclone, further illuminating how spatial distribution of precipitation evolves as the cyclone nears land. Conditional rain rates—focusing on areas experiencing measurable precipitation rather than including dry grids—offer a clearer picture of precipitation intensity trends over time and space.
The central finding is a global uplick in tropical cyclone rain rates just before landfall. Notably, the increase is not uniform across all hemispheres or basins but shows significant intensification particularly in the northern hemisphere and basins such as the Western North Pacific and North Atlantic. This pattern is consistent across different datasets, including the Tropical Rainfall Measuring Mission (TRMM) and the ERA5 atmospheric reanalysis, thereby reinforcing the robustness of the results.
Understanding the dynamics behind this intensification demanded rigorous numerical experimentation using the state-of-the-art Weather Research and Forecasting (WRF) model. By simulating idealized tropical cyclones under varying land surface and radiation conditions, researchers dissected the relative contributions of land feedbacks such as surface friction, thermal contrasts between land and ocean, and atmospheric radiation processes. These experiments provided critical insights into the physical mechanisms fueling increased rainfall as cyclones interact more intensely with coastal environments.
The ideal simulation employed a double-nested domain with high spatial resolution (down to 10 km grid spacing), incorporating realistic boundary layer and microphysics parameterizations. The cyclone’s initial state mimicked typical mid-latitude tropical environments and included a steady easterly steering flow to emulate realistic storm translation towards land. The numerical experiments distinctly isolated the impact of surface type—comparing land-sea contrasts and including or omitting radiation effects—to unravel the multifaceted drivers of rain rate amplification.
Interestingly, the findings suggest that the land-sea thermal contrast and surface friction play pivotal roles in intensifying rainfall rates prior to landfall. The presence of land surfaces alters atmospheric stability and moisture convergence patterns, leading to enhanced condensation and precipitation within the storm’s core and rainbands. Moreover, the omission of radiation schemes in some simulations demonstrated that radiative effects modulate, but do not solely control, the observed precipitation increases.
To quantify atmospheric stability—a key factor shaping tropical cyclone rainfall—the study utilized moist static stability (MSS), defined by the vertical gradient of equivalent potential temperature between the 700 and 850 hPa pressure levels. This parameter effectively captures combined thermal and moisture gradients, which influence convective vigor and rainfall potential in tropical systems. The computation of equivalent potential temperature incorporated temperature, humidity, and pressure fields, allowing for a nuanced evaluation of stability conditions steering precipitation changes.
These findings hold profound implications for disaster management and climate adaptation strategies globally. As tropical cyclones intensify their rainfall delivery prior to landfall, flood risk and associated hazards such as landslides and infrastructure damage will escalate. Accurate forecasting of these intensification patterns is essential for early warning systems, evacuation planning, and resource allocation in vulnerable coastal communities.
This comprehensive investigation bridges observational analysis and numerical modeling to unveil the evolving nature of tropical cyclone precipitation in a warming climate. The research establishes a new baseline for understanding storm-associated rainfall changes and underscores the necessity of incorporating land-atmosphere interactions and radiation processes in predictive models. Policymakers and meteorologists alike will benefit from these insights, which pave the way for enhanced resilience against the mounting threat of increasingly wet and destructive tropical cyclones.
Future research directions spotlight refining model parameterizations related to land surface characteristics and aerosol impacts on radiation, which could further clarify regional disparities in storm precipitation changes. Additionally, extending the temporal scope beyond 2020 using emergent satellite missions and ground-based networks promises to capture ongoing trends amidst accelerating climate shifts. Enhanced interdisciplinary collaboration between climate scientists, hydrologists, and emergency planners is crucial to translate these scientific findings into practical solutions.
The study exemplifies the transformative power of integrating vast, heterogeneous datasets with cutting-edge numerical simulations to decode complex environmental phenomena. By peeling back the layers of tropical cyclone precipitation dynamics prior to landfall, it offers a vital lens into the future risks tropical societies face and signals a clarion call for heightened preparedness as climate change reshapes the storm landscape.
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Zhong, Q., Gan, J., Tu, S. et al. Global increase in rain rate of tropical cyclones prior to landfall. Nat Commun 17, 114 (2026). https://doi.org/10.1038/s41467-025-68070-z
Image Credits: AI Generated
DOI: https://doi.org/10.1038/s41467-025-68070-z
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