The Engineering Research Center (ERC) for the Adaptive Sensing of the Atmosphere (CASA), funded by the National Science Foundation, is integrating a broad spectrum of end-users into the development of remote sensing technology at all levels of design. One such important and yet often-overlooked end-user group is the public. Our research focuses on enhancing our general understanding of group response to tornado warnings. In particular, we seek to understand how group (e.g., coworkers, friends, family, neighbors, or community organizations) structure and interaction impact the warning response process. Role conflict theory and emergent norm theory provide insights into collective behavior and how it could be applied to the public's response to warnings. Previous research on warning response highlights the importance of communication and the role that social conformity plays during periods of emergencies or disasters. We seek to further explore these issues by using data from in-depth interviews (n=52) conducted in Louisiana, Missouri, and Tennessee following tornado warnings. This data was collected as part of a quick-response study by the Disaster Research Center (DRC) at the University of Delaware. Our research identifies and analyzes the stages in the warning response process and explores trends in group structure and interaction.