February 11, 2022 - 3:00 pm
February 11, 2022 - 4:00 pm
CategoriesConvective Meteorology (Mesoscale Dynamics)
Convective Meteorology (Mesoscale Dynamics)
Low Level Stability Analysis of Observed Supercell Environments
Friday, February 11
Lapse rates have long been used to quantify the stability of the environment and aid in the prediction of thunderstorms. Low level lapse rates (0-1 km and 0-3 km) specifically have become a tool in understanding the finer processes that distinguish the environment of tornadic supercells from nontornadic supercells. Several previous studies have attempted to analyze both tornadic and nontornadic supercell environments through simulations and case studies though limited regular point soundings near supercells and in the inflow region of supercells have made larger studies more difficult to conduct. The largest dataset of this type to date was analyzed by Coniglio and Parker (2020) who utilized 430 Great Plains supercell inflow soundings from multiple field campaigns over a 25 year period to analyze supercell environments.
This study expands the Coniglio and Parker (2020) sounding climatology to include soundings from field campaigns in the Southeastern United States. More than 650 soundings within the inflow regions of 210 supercells were binned by distance from the closest supercell. Then low level lapse rates over different depths (100 m, 250 m, 1000 m, and 3000 m) were calculated to analyze the stability of supercell environments. The distribution of lapse rates at each depth was compared between the tornadic and nontornadic supercells as well as the Great Plains and Southeastern soundings. Initial results show that the 0-100 m near storm environment of tornadic supercells is slightly more stable than that for nontornadic supercells and that the differences in stability between nontornadic and tornadic supercells decrease with greater distance and sampling depth. Furthermore tornadic supercell environments favor adiabatic lapse rates in the lowest 100 m, although thereâ€™s large variability in lapse rates near the ground as expected.