New Threat Levels Added to Minimize Alarming Citizenry.

During October 2014, The National Weather Service Storm Prediction Center added two new threat levels to its weather outlooks, so people aren't surprised by bad storms on days with just a "slight risk" of tornadoes, hail or high winds. Forecasters can say whether slight risk days are "enhanced" or "marginal" or just plain "slight." Other categories remain, including "high" and "moderate." The Norman, Oklahoma-based center traditionally targeted local forecasters and broadcasters across the U.S. with their advisories, known as "convective outlooks," but the Internet makes that data available to anyone with a computer and basic scientific knowledge. There were also concerns from broadcasters fearing that their viewers were interpreting terms such as “slight risk” as “no risk.” The system now mimics scales for tornado damage, hurricane strength and the former Homeland Security terrorist threats.During October 2014, The National Weather Service Storm Prediction Center added two new threat levels to its weather outlooks, so people aren't surprised by bad storms on days with just a "slight risk" of tornadoes, hail or high winds. Forecasters can say whether slight risk days are "enhanced" or "marginal" or just plain "slight." Other categories remain, including "high" and "moderate." The Norman, Oklahoma-based center traditionally targeted local forecasters and broadcasters across the U.S. with their advisories, known as "convective outlooks," but the Internet makes that data available to anyone with a computer and basic scientific knowledge. There were also concerns from broadcasters fearing that their viewers were interpreting terms such as “slight risk” as “no risk.” The system now mimics scales for tornado damage, hurricane strength and the former Homeland Security terrorist threats.

Source, National Weather Service

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