Dynamical Downscaling of Major U.S. Tornado Outbreaks

Dynamical downscaling is explored for purposes of reanalyzing historical U.S. tornado outbreaks using data from the 20th Century Reanalysis Project. While this reanalysis has been used in previous research to examine other extreme weather events (e.g., drought and hurricanes), no study has investigated its use for small-scale hazardous convective weather events. Of interest here is the relative utility of coarse resolution boundary condition initialization for purposes of replicating storm scale structure, evolution, and environmental conditions of these significant events. Specifically, modelled updraft helicity and composite reflectivity are used to approximate paths of tornadic supercells for numerous historical high impact convective weather events with few meteorological observations. This methodology could prove beneficial to other studies wishing to reanalyze various mesoscale weather phenomena that may be out of historical range of typical reanalysis datasets.