Chemical, biological, radiological, or nuclear (CBRN) releases pose significant environmental and human exposure risks, especially in urban areas with high population densities. The complex nature of a cityscape brings substantial challenges when determining pollutant dispersal within the urban canopy because wind profiles become altered and turbulence is generated in street canyons and in wake of buildings. This can affect downwind and ground level concentrations after a hazardous release. To better understand complex flow conditions, the Department of Homeland Security (DHS) and Defense Threat Reduction Agency (DTRA) initiated a series of controlled field studies called Jack Rabbit II (JRII) in 2015 and 2016. Sequences of 10-20-ton releases of chlorine gas were dispersed within an array of CONEX shipping containers to mimic buildings or other roughness elements. Boundary layer wind flow characteristics were also collected using sonic anemometers, but the data have largely not been analyzed. The goal of this study is to present a preliminary analysis of the JRII wind flow dataset to inform urban adjustments in Gaussian dispersion models. Modifications to the local wind profile and turbulence terms could lead to improved boundary layer parameterizations in dispersion models, which are important for efficient and precise emergency preparation and response.