The Quick Urban & Industrial Complex (QUIC) dispersion modeling system is evaluated using street-level wind and concentration measurements taken during the Joint Urban 2003 Field Experiment held in downtown Oklahoma City. A number of improvements to the empirical-diagnostic wind solver to better account for high-rise buildings and dense urban areas will be discussed. Comparison to street-level wind measurements in the downtown area show much better agreement using the new schemes. Point-by-point comparisons with concentration measurements for the Westin release show reasonable agreement as well. Sensitivities to the ambient wind speed, wind direction, and stability will be discussed.