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A Hazard Multiple: Overlapping Tornado and Flash Flood Warnings In A National Weather Service Forecast Office In The Southeastern United States


The U.S. weather warning system is designed to help operational forecasters identify and issue alerts for hazards that assist people in taking life-saving actions. Assessing risks for individual hazards, such as flash flooding, can be challenging for individuals, depending on their contexts, resources, and abilities. When two or more hazards co-occur in time and space, such as tornadoes and flash floods, which we call TORFFs, individual risk assessment and available actions people can take to stay safe become increasingly complex and potentially dangerous. TORFF advice can suggest contradictory action–that people get low for a tornado and seek higher ground for a flash flood. The origin of risk information about such threats is the National Weather Service (NWS) Weather Forecast Office. This article contributes to an understanding of the warning and forecast system though a naturalistic study of the NWS during a TORFF event in the Southeastern United States. Drawing on literature for the Social Amplification of Risk Framework, this article argues that during TORFFs, elements of the NWS warning operations can unintentionally amplify or attenuate one threat over the other. Our results reveal three ways this amplification or attenuation might occur: 1) underlying assumptions that forecasters understandably make about the danger of different threats; 2) threat terminology and coordination with national offices that shape the communication of risks during a multi-hazard event; and 3) organizational arrangements of space and forecaster expertise during operations. We conclude with suggestions for rethinking sites of amplification and attenuation and additional areas of future study.

Article / Publication Data
Available Metadata
Accepted On
May 06, 2020
Early Online Release
July 06, 2020
Fiscal Year
Peer Reviewed
Publication Name
Weather and Forecasting
Published On
August 01, 2020
Publisher Name
American Meteorological Society
Print Volume
Print Number
Page Range
Submitted On
October 18, 2019


Authors who have authored or contributed to this publication.

  • Jennifer Henderson - lead Gsl
    Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder
    NOAA/Global Systems Laboratory