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The National Weather Service (NWS) communicates threats to partners and constituents via a product called the impact based warning. The goal of this process is to focus on providing more information to media and emergency managers, facilitating improved public response and decision making; and meeting societal needs in the most life-threatening weather events. The impact based warning will have “event tags” at the bottom of each severe thunderstorm and tornado warning. The additional tornado event tags will have tornado threat information attached to them as a quick means to provide users and partners with potential high impact signals that prompt faster risk assessment and protective action.


Currently, all Weather Forecast Offices serving the contiguous United States are utilizing the impact based warning format. More information concerning the look of the warnings is available in the Examples section


For more information concerning the impact based warning project, please contact:

Jim Keeney
Severe Weather Program Lead