We thank Dr. Brian Fiedler for the use of his model, Drs. Harold Brooks and Erik Rasmussen for critiquing a draft of this paper, and Ms. Joan O’Bannon for drafting Fig. 14. Part of this research was inspired by a discussion with Dr. Richard Rotunno, whose comments along with those of the two other reviewers are appreciated. Participation in the Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX) helped the authors to reach their conclusions. This work was performed while one of the authors (R.J.T.) was a National Research Council-NOAA Postdoctoral Research Associate.
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