Andy Dean (SPC) provided valuable assistance in filtering the severe events and Jason Levit (NWS headquarters) laid the initial groundwork for filtering the severe events. David Cleaver (SPC) helped develop computer code to display some data in GIS. This work also benefitted from multiple discussions with Steven Weiss and Dr. Russell Schneider (SPC). The authors express their gratitude to Les Lemon, Jim LaDue, and Paul Schlatter of the Warning Decision Training Branch for reviewing and discussing our radar interpretation for several difficult convective mode cases. The thorough reviews by Matt Bunkers, Les Lemon, and one anonymous reviewer helped clarify and strengthen our presentation.
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Level III archived data were used when level II data were missing, or when a site with only level III archived data provided superior resolution of an event.
We refer to EF-scale damage ratings for all tornadoes, though the enhanced Fujita scale was not implemented until February 2007. The F-scale tornado damage ratings in prior years correspond to the same numerical rating on the EF scale for the same type of damage, though the EF scale includes more specific damage indicators.