Understanding Tornado Warnings: An Analysis of Trends in Risk Communication and Lead Time Performance

The Weather Research and Forecasting Innovation Act of 2017 aimed to support performance improvements related to the National Oceanic and Atmospheric Administration’s (NOAA) weather forecasting and prediction of high-impact weather events, and mandated the creation of a Tornado Warning Improvement and Extension Program (TWIEP). The TWIEP’s goal is “to reduce the loss of life and economic losses from tornadoes through the development and extension of accurate, effective, and timely tornado forecasts, predictions, and warnings, including the prediction of tornadoes beyond one hour in advance.” This presentation uses a combination of methods (i.e., quantitative, literature reviews, qualitative, semi-structured interviews, site visits, etc.) to explore if NWS’s policies and usage of risk communication in tornado forecast, predictions, and warnings have affected actions to reduce the loss of property and life with an emphasis on vulnerable communities.

This presentation will discuss tornadoes’ impact to society and behavioral outcomes with a focus on NWS’s tornado forecasts, watches, and warnings. We found the NWS has invested in increasing communication, particularly risk communication with core partners during the provision of impact-based decision support services (IDSS), in the periods after tornado watches but before tornado warnings are issued. While there have been reports of significant increases in risk communication between NWS staff and core partners, the effects for decision-making are not well understood. We provide recommendations to address the findings of this report.