Near‐Surface Maximum Winds During the Landfall of Hurricane Harvey. Issue 2 (16th January 2019) - Alford, A. Addison
Abstract: A mobile Shared Mobile Atmospheric Research and Teaching (SMART) radar was deployed in Hurricane Harvey and coordinated with the Corpus Christi, TX, WSR‐88D radar to retrieve airflow during landfall. Aerodynamic surface roughness estimates and a logarithmic wind profile assumption were used to project the 500‐m radar‐derived maximum wind field to near the surface. The logarithmic wind assumption was justified using radiosonde soundings taken within the storm, while the radar wind estimates were validated against an array of StickNets. For the data examined here, the radar projections had root‐mean‐squared error of 3.9 m/s and a high bias of 2.3 m/s. Mesovorticies in Harvey's eyewall produced the strongest radar‐observed winds. Given the wind analysis, Harvey was, at most, a Category 3 hurricane (50–58 m/s sustained winds) at landfall. This study demonstrates the utility of integrated remote and in situ observations in deriving spatiotemporal maps of wind maxima during hurricane landfalls. Plain Language Summary: Measurements of extreme winds during hurricane landfall are difficult to obtain due to sparsely populated observing systems that cannot capture the complete distribution of the wind field. The wind fields are needed to refine building codes in hurricane prone areas and to delineate damage caused by wind versus water during poststorm assessment, particularly for insured losses. By using three‐dimensional winds retrieved from two ground‐based Doppler radars, the maximum wind distribution of Hurricane Harvey was analyzed. The radar winds were projected to the surface and validated against a network of anemometers, yielding close agreement. The analysis showed that Harvey was, at most, a Category 3 (sustained winds between 50 and 58 m/s) strength storm at landfall. Additionally, perturbations in the eyewall similar to the parent circulation of tornadic storms led to the strongest flow observed near the surface. Key Points: Dual‐Doppler wind retrievals show that Harvey was, at most, a Category 3 hurricane at landfall Mesovortices in the inner eyewall of Hurricane Harvey produced the strongest flow observed in the storm Mobile Doppler radar and in situ surface and upper air networks can improve estimates of near‐surface winds during hurricane landfall