Using the National Weather Service's impact-based decision support services to prepare for extreme winter storms

In recent years, the National Weather Service (NWS) increased its focus on providing decision support services to the emergency management community and other core partners to help them understand its forecasts and take appropriate actions in the face of upcoming extreme events. In 2011, the Weather-Ready Nation Strategic Plan began to formalize the NWS approach to impact-based decision support services (IDSS). NWS recognizes IDSS as a primary service and is working to fully and more effectively provide it to federal, state, local, and tribal decision-makers. To do so, it is important that NWS understands how users are benefiting from existing IDSS, even as they look to improve it. This article aims to provide emergency managers (EMs) with an understanding of the efficacy of IDSS. The authors define IDSS and describe the IDSS products and services available during each stage of the emergency-management cycle: preparedness, mitigation, response, and recovery. To demonstrate the role of IDSS for the emergency management community, the authors use a case study analysis to compare two winter storms in the New York City area with similar characteristics but differing in their implementation of IDSS: the December 2010 winter storm (no formal IDSS) and the January 2016 winter storm (formal IDSS). In comparing the winter storm case studies, the authors find that formal IDSS provides EMs and other core partners with accurate, actionable, and consistent weather information and support that allows them to respond to winter storms in a way that reduces impacts to lives and livelihoods.