Houston area has a pollution problem due to a combination of emissions from mobile and industrial sources as well as complicated meteorological phenomena of a coastal urban area. A Study of Houston Atmospheric Radical Precursors (SHARP) was carried out in spring 2009. Here we present modeling results of SHARP 2009 using the Weather Research Forecast model and the Community Multiscale Air Quality model (WRF-CMAQ). Process analysis tool is utilized to analyze photo-chemical processes leading to ozone production and chemical transformations along trajectories linking a site at the Houston Ship Channel and the University of Houston Moody Tower site. Furthermore, WRF-CMAQ results will be shown to elucidate the relative importance of radical sources in the Houston atmosphere.