Although tornado production in supercells may be largely dependent on storm scale and meso-beta scale processes (eg, Markowski et al, 1998a and 1998b), larger scale environmental parameters have long been associated with supercell and tornado potential (eg, Davies-Jones 1993, Lemon and Doswell 1979). Without nationwide, real-time observational data on the smaller scales, forecasters must continue to depend on broader influences on thunderstorm character and morphology when evaluating the potential for severe weather. This includes applications of mesoscale prediction models that are operationally run many times daily.

In that theme, we used hourly Rapid Update Cycle 2 (RUC-2) model soundings to independently assess the utility of various published supercell and tornado forecasting parameters, and to compare them for various subsets of tornadic and nontornadic supercells. Because these variables are available to most forecasters, and because the RUC-2 is generally a robust and timely tool for evaluating the sounding environment near supercells (Thompson and Edwards 2000a), it can be used to evaluate the utility of these parameters.