Examining Extreme Rainfall Forecast and Communication Processes in the South-Central United States

Abstract

Abstract Extreme rainfall events are hazardous and costly. They have increased in parts of the United States, and climate models project that trend to continue. Effective communication of potential threats and impacts associated with extreme rainfall events is one of the foci of a weather forecaster’s job and aligns with the National Weather Service (NWS)’s mission to protect life and property. This research investigated how NWS forecasters processed and communicated information about extreme rainfall events that occurred in the south-central United States between 2015 and 2019. The study also explored forecasters’ perceptions of the relationship between the events and climate change and whether those perceptions impacted the forecasts, including how forecast information was communicated. Semistructured interviews were conducted with 21 NWS forecasters about how they internally processed and externally communicated model outliers and anomalous rainfall events. Thematic analysis of the interview data identified components of sensemaking and decision-making conceptual frameworks as well as principles of forecasting. These components were then combined to create an extreme event forecast communication process model to illustrate the findings. Although forecast and communication processes are complex and vary between offices and forecasters, the communication process model presents a high-level conceptualization of how forecasters translate highly technical and disparate material into usable information for their audiences within the context of rare meteorological events. Significance Statement This study presents an extreme event forecast communication process model that helps to explain how National Weather Service forecasters process and communicate extreme rainfall events. Forecasters were interviewed about their experience with extreme rainfall events. Effective communication of such events is important because they can lead to significant, and sometimes deadly, impacts. In the future, the extreme event forecast communication process model might provide a framework for best practices and be incorporated into forecaster training materials. Additional research is needed to determine whether the model applies to regions outside the south-central United States.