Tornado on a Leash: Assessing Azimuthal Shear and Rotational Velocity in Violent Tornado Tracks

In a collaborative project that involves scientists and forecasters at the Storm Prediction Center and National Severe Storms Laboratory, this project aims to analyze a growing database of observed supercells and tornadoes to address the gaps in knowledge of various aspects (i.e., tornado-warning performance and background environment) of these storms. The overarching goal is to better understand supercell thunderstorm environments, evolution, tornado production, and warning characteristics. We used coding techniques (e.g., Python) to further analyze specific tornadic (and nontornadic) supercell cases to highlight the difference in environments, evolutionary paths, etc. Using radar data retrieval and analysis to help construct a supercell and tornado database, four specific supercell events were chosen to analyze. Deriving azimuthal shear (AzShear) of the MRMS Rotational Track product and plotting rotational velocity (Vrot) from the SPC Vrot Tool at the lower (~ 1.5 km) and mid-levels (~ 4.5 km), this study will discuss relationships between these variables for mesocyclonic and tornadic strength during long-lived and other supercells. AzShear and Vrot time series throughout the storm tracks are assessed, as well as the variability of these products with radar distance and elevation. This presentation will discuss the opportunity to compare Vrot and AzShear in order to encourage a more weather-ready nation, via a transition of increased knowledge of storm-scale processes to improved real-time predictability.