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The Rapid Refresh model (Benjamin et al. 2007) operationally replaced the RUC on 1 May 2012. Its efficacy in the TC environment, both on its own and as an influence in SPC mesoanalyses, is yet to be determined.
The term “EF” is used for the damage ratings of all tornadoes herein, including those rated prior to the enhanced Fujita scale's implementation in February 2007, because of the correspondence in F- and EF-scale ratings intrinsic to the development of the latter (WSEC 2006).
Due to data outage, one event from this subset had no environment data except STP.
Due to a data outage, one event from this subset had no environment data except STP; two others lacked all but SCP and STP.
Because of a data outage, one event from this subset had no environmental information. Cases with most or partial missing environment data account for the presence of more total mode events than in the corresponding environmental analyses in section 3d and Fig. 7.
See Edwards (2012) for further discussion on the uncertainties involving eyewall-tornado reports in general.
Damage ratings, especially in the F-scale era, were not necessarily direct functions of actual tornado intensity (Doswell and Burgess 1988), but instead, mere indicators, and even then, only if a suitably robust target was hit to represent maximum tornado winds. Given the small, brief nature of TC tornadoes in general, and their occasional spatial juxtaposition with hurricane damage, undersampling issues raised by Doswell and Burgess may apply here. No violent (EF4 and EF5) tornadoes were found in the dataset. Further, since maximum EF-scale rating was used as the grid-box filter, the actual ratio of weak (EF0 and EF1) tornadoes to all tornadoes is higher than in the events presented here.
Finer-resolution automated analyses that are out of this study's scope recently have become available as material for similar testing, once TC sample sizes can grow for them, for example, the Space and Time Multiscale Analysis System (STMAS, after Xie et al. 2011) and Real-Time Mesoscale Analysis (RTMA, after De Pondeca et al. 2011). These do not offer as many fields as the SPC mesoanalyses (Bothwell et al. 2002), but can provide base-state variables and (with STMAS) some derived parameters.