Date of Award
2024
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Atmospheric and Earth Science
Committee Chair
Lawrence Carey
Committee Member
Kevin Knupp
Committee Member
Sean Freeman
Research Advisor
Kevin Knupp
Subject(s)
Tornadoes--Forecasting, Severe storms--Forecasting, Dopper radar, Convection (Meteorology)
Abstract
On 01 April 2023, a severe QLCS impacted Northern Alabama during the PERiLS field campaign under High-Shear/Low-CAPE (HSLC) conditions, with CAPE below 1000 J/kg and 0-6 km wind shear exceeding 25 m/s. This study examines the mesoscale variability and tornadogenesis within the QLCS. Ceilometer and Radar Wind Profiler data indicated lowering cloud bases and shifts in the boundary layer winds. Surface analyses revealed a cold pool strength of -9◦C at the tornadogenesis location, with significant spatial variability. Storm Relative Helicity values decreased from nearly 900 to 350 m2/s2 by 0800 UTC. A lightning jump around 0756 UTC coincided with a strengthening updraft and increased Vertically Integrated Liquid values of 15-18 kg/m2. Dual-Doppler analyses on a 70 km baseline retrieved vertical motion of 11-13 m/s without a background wind field from a sounding, but radar resolution limited some observations.
Recommended Citation
Huggins, Joshua L., "Assessing the mesoscale variability and rapid tornadogenesis in the high-shear/low-CAPE, surging QLCS in Northern Alabama on 01 April 2023" (2024). Theses. 708.
https://louis.uah.edu/uah-theses/708