Since most of the primary atmospheric Pollutants are emitted inside the roughness sublayer (RSL) and consequently the first chemical reactions and dispersion occur in this layer, it is necessary to generate detailed meteorological fields inside the RSL to perform air quality modeling at high spatial resolutions. At neighborhood scale (1 km horizontal grid) the meteorological fields are strongly influenced by the presence on the vegetation and building morphology of varying complexity. This requires development of more detailed treatment of the influence of canopy structures in the models and using additional morphological databases as input. As a result of this a detailed urban and rural canopy parameterization has been developed inside the Penn State/NCAR Mesoscale Model (MM5) to simulate the meteorological fields within and above the urban and rural canopies. It is called DA-SM2-U. This paper applies the DA-SM2-U version of MM5 to Houston, Texas in order to study the influence of the morphological parameter resolution on the meteorological fields to know it a detailed resolution of these parameters is required for simulating at neighborhood scales. This paper gives a brief description of the DA-SM2-U model and the procedures used to create the morphological parameters on Houston. The first results of the influence study of the representation of the city of Houston on the structure of the urban boundary are presented.