The Benefits and Challenges of Implementing Impact-Based Severe Weather Warning Systems: Perspectives of Weather, Flood, and Emergency Management Personnel

Abstract Warnings about impending hazards help to minimize the impacts and reduce the risk of the hazard through encouraging an appropriate and timely behavioral response. Many hydrometeorological agencies are moving toward impact-based forecast and warning (IBFW) systems, as encouraged by the World Meteorological Organization. Yet little research has been conducted on such systems from the perspectives of agencies who are or would be involved in their implementation. We investigated the challenges and benefits of IBFW systems as perceived by participants from agencies internationally and within New Zealand. Interviews and workshops were held with meteorologists and weather forecasters, flood forecasters and hydrologists, and emergency managers. We found that the benefits of implementing IBFW systems included a perceived increase in the understanding of the potential impacts by the public, added awareness of antecedent conditions by forecasters, a possible reduction in “false alarms,” and increased interagency communication. Challenges identified by the participants included whether the system should be designed for individuals or society, a lack of impact data, verification of warnings based on impacts, a conflict with roles and responsibilities, the potential for conflicting messages, and the increased burden on agencies providing information to forecasters with a perception of little benefit in return. We argue that IBFWs could be designed for individual members of the public, with an increased focus on understanding vulnerability and capacities, and that more impact data need to be collected and stored to inform future warnings. Increased interagency coordination would assist with rapid decision-making and the success of IBFWs.