Structures of Cold Pools from PERiLS 2022 & 2023

The Propagation, Evolution, and Rotation in the Linear Storms (PERiLS) field campaign is one of the first to focus on sampling environmental and storm-scale processes associated with tornadic quasi-linear convective systems (QLCSs). QLCS tornadoes present operational forecasting challenges in the Southeastern United States, in part because they are less well-understood than supercellular tornadoes, and in part, because they frequently occur in environments with large low-level vertical wind shear and weak instability (commonly known as “high-shear, low CAPE”, or HSLC, environments). One way to address such forecasting challenges is to gain more knowledge about the environmental and internal processes that contribute to the severity of HSLC QLCSs. One in-storm feature specifically targeted by PERiLS is the cold pool. Cold pools play an important role in QLCS maintenance, being linked to the development of new convective cells as well as the mesoscale flow branches that lead to widespread regions of stratiform precipitation. Cold pools are also responsible for generating horizontal vorticity due to their baroclinity, which may play an important role in tornadogenesis. Understanding cold pools’ structures and properties on short time and space scales within QLCSs that form in an HSLC environment is a first step toward resolving the underlying processes that contribute to QLCS severity.

This study incorporates data from the first and second PERiLS field campaigns (March-April 2022 and February-May 2023) using mobile mesonets, surface pods, upper-air soundings, and Sticknets. We will characterize the heterogeneity and variability of the cold pools from 12 observed QLCSs (having both classical and non-classic structures).