Abstract
This study investigates the impact of land‐surface roughness on surface winds during hurricane Wilma's landfall using high‐resolution simulations by the Weather Research and Forecasting model. Based on idealized experiments with enhanced land‐surface roughness, it is found that the overall storm intensity decreases with increase in land‐surface roughness during landfall. However, there is no apparent trend in reducing the maximum gusting winds when land‐surface roughness was increased. This result suggests that hurricane wind damage may not be assessed properly based solely on the overall storm intensity. The localized damaging winds are intimately involved with the hurricane boundary‐layer secondary circulations. When the downdraughts of the circulations are in phase with the strong hurricane momentum aloft, they can effectively transport momentum downward to result in localized damaging winds. Larger land‐surface roughness can strengthen boundary‐layer secondary circulations by creating stronger local convergence, and thus stronger downdraughts and localized damaging winds despite a weak storm intensity. Copyright © 2008 Royal Meteorological Society