Contrasting the Environments of Supercells that Produce Simultaneous and Violent Tornadoes

We have made great strides in forecasting tornadoes and the environments in which they form in the past few decades. Numerical weather prediction models have become more successful in portraying regions where severe thunderstorms are possible and suggesting potential threats associated with these storms, including large hail, damaging winds, and tornadoes. Some supercells, however, produce more than one tornado simultaneously. While all tornadoes pose a threat to life and property, simultaneous tornadoes can yield a greater threat. Using the tornado database (1995-2022) from the Storm Prediction Center, pairs of simultaneous tornadoes were identified. Next, storm mode was determined from archived radar imagery to ensure that the tornadoes were produced by supercells. Only tornadoes greater than EF/F-1 strength were considered. These criteria yielded 61 pairs of simultaneous tornadoes. Next, observed proximity soundings were obtained and several environmental parameters were calculated, including CAPE, CIN, bulk wind shear, and storm-relative helicity. Only tornado pairs for which a valid proximity sounding exists were considered further, reducing the sample size to 28 tornado pairs. Violent (F/EF-4+) tornadoes were then selected from the archive such that the seasonal and geographic distribution matched that of the simultaneous tornadoes and proximity soundings were obtained and environmental parameters were calculated as before. The parameters were then averaged and compared between the two groups.