Public health officials seek to identify the most vulnerable communities to tailor emergency messages during wildfire smoke events. However, previous efforts typically report global estimates for a region or wildfire event. In a study funded by the University of California and the California-Nevada Climate Applications Program (CNAP), a CPO Regional Integrated Sciences and Assessments (RISA) team, researchers apply a new approach to better identify where and when major respiratory impacts develop during major wildfires near urban locations. They used a spatial within-community matched design analysis, coupled with a Bayesian Hierarchical Model, in the context of San Diego County wildfires in 2007. This study considers actual respiratory hospitalizations by zip code on a daily basis before, during, and after an exposure event. The authors’ approach captures variation in health impact as smoke plumes shift due to regional winds. The study confirms the high impact towards communities immediately downwind of the fire, but also finds disproportionate impact along the heavily populated coast where smoke exceeded health standards despite being diluted.