Tweeting the Heat: An Analysis of the National Weather Service's Approach to Extreme Heat Communication on Twitter

Abstract Heat communication interventions are an essential way that public safety organizations can reduce extreme heat consequences for at-risk groups. Although the aim of these interventions is typically behavior change, these organizations commonly assume that providing information about heat risks, impacts, vulnerable populations, and protective actions will lead individuals to protect themselves. However, behavior change is a complex process whereby messages must be crafted in ways that increase their persuasive effects. To examine the extent to which key assumptions about behavior change are present in public safety organizations’ heat communication interventions, we examine 250 heat-related tweets sent by seven National Weather Service (NWS) weather forecast offices (WFOs) in 2021. We find that these NWS WFOs use technical language or “jargon” to communicate about heat risks and impacts. In addition, we find that information about vulnerable populations and protective actions is not presented in a way that conforms to theory on behavior change. Based on these results, we offer recommendations to increase the persuasiveness of NWS WFO communication interventions that encourage the public to protect themselves during extreme heat events. Significance Statement Heat is the leading cause of death among all weather-related hazards. How heat is communicated to the public can help mitigate heat-related morbidity and mortality. However, heat communication interventions are often developed with several embedded assumptions about behavior change that negatively impact their effectiveness. By examining how a key public safety organization communicates about heat on social media, and the extent to which these assumptions are present, we offer recommendations to increase the persuasiveness of NWS heat communication on social media.