The Role of NWSChat in Integrated Warning Team Communications

A severe weather warning system detects or forecasts natural hazards and disseminates information through warning channels (such as sirens, television, text messages) so that the public may take protective action with the goal of minimizing deaths, injuries, property loss, and business disruption. The different parts of the integrated warning team, such as National Weather Service forecasters, media, emergency managers, spotters, all play interconnected roles in the warning system, detecting hazards, making warning decisions, managing the flow and content of information, and responding to the information. Official warning systems, such as the National Weather Service's severe weather warning and emergency managers' outdoor siren activation, exist along side informal warning systems where families text one another, use social media, and respond to environmental cues. The interaction of these official and informal warning with exogenous factors such as the natural, social, and built system, determines the socioeconomic outcome of the hazard.

Hazards researchers have developed a conceptual model for warning systems that includes three linked sub-systems for detection, management, and response. For severe weather warning, this concept can be mapped to: 1) a hazard detection sub-system that predicts if a hazard will occur with a level of certainty, lead time, spatial area, intensity, and predicted path, primarily involving NWS forecasters and spotters; 2) a management sub-system that communicates information about the hazard to the public, primarily involving emergency managers and media; and 3) a public response sub-system that encompasses all of the complex factors which influence individuals' decisions to take protective action. In such an interdependent system, the performance of one sub-system impacts the others, and the communications that link the sub-systems are critically important.

NWSChat is one of the principal communications tools for linking the detection sub-system and the management sub-system. NWSChat is an instant messaging system where NWS forecasters can share official warning information and their interpretation of an evolving hazardous weather situation with the rest of the integrated warning team. It is also a platform where NWS forecasters receive information from spotters and emergency mangers from the field, providing a critical source of information for forecaster decision making. Through a content analysis of NWSChat in the NWS Dallas Fort Worth County Warning Area for selected severe weather events from 2007 – 2014, we will discuss how weather risk is communicated among integrated warning team members, focusing on their different roles and interests, and the geographic specificity and certainty of communications. We will then show how this information can help determine if technical or communications interventions could improve integrated warning team and warning system performance. The introduction of very high resolution CASA radar data (X-band radars) to the detection sub-system in the DFW Metroplex and the impact on IWT communications will be used as an example.