Investigating the Ability of the Three-Ingredient Method Using CM1 Simulations

One method for predicting tornadogenesis in quasi-linear convective systems (QLCS) is called the three-ingredient method (3IM). The three ingredient method states that if the following ingredients are present, then tornadogenesis is likely to occur. Those three ingredients are: a portion of a QLCS in which the system cold pool and ambient low-level shear are nearly balanced or slightly shear dominant, where 0-3 km line normal bulk shear magnitudes are equal to or greater than 15 m/s (30 knots), and a RIJ or enhanced outflow causing a surge or bow in the line. 3IM first emerged as a result of Schaumann and Przybylinksi’s paper in 2012, where they discovered that QLCS tornadogenesis is likely to occur when those three specific criteria are met. Since this initial study was released, multiple other papers have analyzed the capabilities of 3IM in detail using observations. The present project will focus on testing each of the proposed ingredients using Cloud Model 1 (CM1), to assess if the simulations can reproduce the operational utility of 3IM. Specifically, the simulations test varying shear profiles and different cold pool strengths. The simulations feature a horizontally stretched grid that has spacing as low as 100m and as high as 1000m, the full dimensions of the simulation are 288 km by 144 km with a height of 17.25 km. Initial results corroborate the findings from previous papers, showing more frequent and intense tornadolike vortices when the cold pool and shear are balanced. However, more results will be presented, using individually controlled cold pool strength and shear magnitude.