This graphic provided by NOAA's Storm Prediction Center shows a severe weather outlook for April 27, 2011. The Storm Prediction Center is adding two threat levels to its U.S. weather outlooks so ... more 
This graphic provided by NOAA's Storm Prediction Center shows a severe weather outlook for April 27, 2011. The Storm Prediction Center is adding two threat levels to its U.S. weather outlooks so people aren't surprised by really bad storms on days with just a "slight risk" of tornadoes, hail or high winds. Beginning Oct. 22, 2014, forecasters can say whether slight risk days are "enhanced" or "marginal." Other categories remain, including "high" and "moderate." (AP Photo/NOAA) less 
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Associated Press | Photo By NOAA
Mon, Aug 11, 2014 11:12 PM EDT