In this study, high-resolution numerical simulations on the local wind system in an urban canopy are carried out by using two classes of numerical models, and the features of severe winds in various buildings are examined. Wind fields in an urban scale are simulated by using a mesoscale meteorological model, while turbulent flow fields within the urban canopy are calculated by using large-eddy simulation model that incorporates explicitly the effects of buildings and structures. In the LES calculations high-resolution GIS data are used, and thereby realistic surface roughness in the urban area is reproduced. This research demonstrates more local and gusty winds within the urban canopy than simulated only with a mesoscale model, which will improve the prediction accuracy of a severe wind disaster.
