Environmental Evolution of Long-Lived Supercell Thunderstorms
Dr. Casey Davenport
Assistant Professor, University of North Carolina-Charlotte
October 16, 2020 at 2:00pm
Remotely via Microsoft Teams
Long-lived supercells (> 4 hours) are relatively rare, but present significant risk for society as a result of their intensity and associated hazards over an extended time period. The persistence of a rotating updraft is tied to near-storm environmental characteristics; however, given the prevalence of mesoscale environmental heterogeneity near convection, it is unknown to what extent those near-storm characteristics vary over the lifetime of a supercell, nor how quickly the storm responds to such changes.
This study examines nearly 150 long-lived, isolated supercells, focusing on the evolution of their near-storm environments using model analysis soundings collected each hour throughout the storm’s lifetime. Diurnal and maturity-relative distributions of common forecasting parameters will be shown, along with comparisons among subsets such as marginally vs. very long-lived and severe weather production. The goal of such analyses is to enhance short-term forecasts of supercells by better anticipating storm evolution as a result of environmental variations.