Using Ground-Based Mobile Profiling Systems to Explore the Impact of Terrain Heterogeneity on Boundary Layer Processes Related to the Development of Near-Surface Vorticity During PERiLS

Storm-scale processes in the atmospheric boundary layer remain among the most complicated problems in atmospheric science. Idealized simulations have provided a framework for how classic supercell dynamics contribute to the generation of near-surface vertical vorticity that is necessary for tornadogenesis. However, a large portion of observed tornadoes, particularly in the southeast United States, are produced by quasi-linear convective systems (QLCSs) that have different low-level dynamic characteristics than classic supercells. During the springs of 2022 and 2023, the PERiLS field campaign supported the deployment of a large array of observation platforms to explore QLCS and associated tornadoes in the Southeast. The PERiLS observation network included the Collaborative Lower Atmospheric Mobile Profiling System (CLAMPS), a remote sensing profiler that collects high temporal resolution observations of the atmospheric boundary layer. During PERiLS-2022, two CLAMPS systems were deployed in the Mississippi Delta region to probe the pre-convective boundary layer. One of these systems was positioned on the eastern periphery of the Delta, where there is a pronounced gradient in terrain structure and canopy coverage. This talk uses data from both CLAMPS to explore how terrain heterogeneity may prompt locally enhanced near-surface vorticity through modification of the low-level flow structure in the pre-convection environment.