A Review of Near Storm Environmental and Storm Structure Characteristics of Thunderstorms that Resulted in False Alarm Tornado Warnings Across Central and Eastern Iowa
The NSE data were collected using the Storm Prediction Center's mesoscale analysis data which was originally based on merging an objective surface analysis and the latest 40 km RUC. The RUC has more recently been replaced with the Rapid Refresh (RAP) model. Examination of fourteen NSE parameters commonly used to assess tornadic potential found low level kinematic predictors such as 0-1-km shear and effective storm relative helicity in addition to mixed layer lifting condensation levels were superior discriminators between tornadic and FAR events. Events were finally filtered by storm type with a vast amount of the FAR events occurring with either quasi-linear convective systems or high precipitation supercell to bow echo transition cases. In addition, supercell mesocyclone characteristics including rotational velocity, depth and width were analyzed. These results are compared and contrasted using graphical displays and statistical techniques.