Journal Article

A New Framework for Evaluating Model Simulated Inland Tropical Cyclone Wind Fields

Zhou, Linjiong, Morin, Matthew, Harris, Lucas, Marchok, Timothy, Chen, Jie, Gao, Kun

2023

Overview

Though tropical cyclone (TC) models have been routinely evaluated against track and intensity observations, little work has been performed to validate modeled TC wind fields over land. In this paper, we present a simple framework for evaluating simulated low‐level inland winds with in‐situ observations and existing TC structure theory. The Automated Surface Observing Systems, Florida Coastal Monitoring Program, and best track data are used to generate a theory‐predicted wind profile that reasonably represents the observed radial distribution of TC wind speeds. We quantitatively and qualitatively evaluated the modeled inland TC wind fields, and described the model performance with a set of simple indicators. The framework was used to examine the performance of a high‐resolution two‐way nested Geophysical Fluid Dynamics Laboratory model on recent U.S. landfalling TCs. Results demonstrate the capacity of using this framework to assess the modeled TC low‐level wind field in the absence of dense inland observations. Plain Language Summary Some of the biggest human impacts of tropical cyclone (TC) winds come after the TC makes landfall. A skillful prediction of the radial distribution of winds is essential for forecasting TC‐induced inland hazards. However, the forecast skill of numerical hurricane models on inland TC wind fields has rarely been evaluated since it is challenging to collect wind observations during landfall, and the network of regular weather observations is too spread out to capture the strongest winds associated with a TC. This inhibits the improvement of forecast models and limits our understanding of the TC's inland evolution. Our work combines available inland in‐situ wind observations over the southeastern U.S. with existing TC structure theory, and presents a new “optimal” estimate of the post‐landfall winds. Our framework is found to be useful for evaluating the post‐landfall TC winds in hurricane forecast models. In addition, the new evaluation technique can intuitively demonstrate how well the model simulates TC intensity and structure. Key Points We introduce a new framework for evaluating modeled inland tropical cyclone (TC) wind fields with observation‐based, theory‐predicted wind profiles The theory‐predicted wind profile well represents the observed radial distribution of inland TC wind speeds We propose simple indicators to summarize the model performance on inland wind field predictions

• Publisher: John Wiley & Sons, Inc,Wiley
• Subject: Cyclones / Distribution / Environmental monitoring / Fluid dynamics / Frameworks / Geophysical fluids / Human influences / Hurricane forecasting / Hurricane models / hurricane risk / Hurricanes / Hydrodynamics / Mathematical models / model evaluation / Modelling / Radial distribution / Scale models / Simulation / TC inland wind field / TC landfall / Theories / Tropical cyclone intensities / Tropical cyclones / Wind / Wind fields / Wind observation / Wind profiles / Wind speed / Winds