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While the Weather Research and Forecasting Innovation Act of 2017 calls for improving the prediction of tornadoes beyond one hour, research suggests that lead times in the one hour range may make the public less likely to respond with the same sense of urgency.
Recently, the Washington Post Capital Weather Gang wrote an interesting article about advanced tornado warnings. They reported that lead time for tornado warnings is down to about nine minutes as compared 13-15 minutes (2005 to 2011). At this point, gather yourself, breathe and resist the urge to conclude or tweet that forecasters are bad and getting worse. New modeling capabilities, radar technology and forecaster understanding may actually be enabling more skilled forecasts. So what gives?
Analyses reveal that strong emphasis on reducing false alarms may be driving the decline in lead time. In other words, lead time has suffered, but there are less instances of "cry wolf" (see figures below). Data also show that weaker EF0/EF1-rated tornadoes may be affecting the statistics (more on that later in the discussion). It is a complex discussion involving many factors.