Effects of the Low-Level Wind Profile on Outflow Position and Near-Surface Vertical Vorticity in Simulated Supercell Thunderstorms

• DOI: 10.1175/jas-d-17-0174.1
• Publication Date: 2017-12-15T21:42:22Z
• Authors: Felicia Guarriello; Christopher J. No...; Craig C. Epifanio
• Keywords: Mesocyclone; Supercell; Outflow; Thermal wind

Abstract Supercell thunderstorms are simulated using an idealized numerical model to analyze the effects of modifications environmental low-level wind profile on near-surface rotation. Specifically, orientation, magnitude, and depth vertical shear modified in several suites experiments compared control simulations with no prescribed layer. The overall morphology supercells is highly sensitive even shallow changes profile. Moreover, maximum vorticity varies as modified. results suggest this principally a consequence degree which favorable dynamic forcing negatively buoyant outflow superimposed upon circulation maximum. Simulations easterly weaker storm-relative winds over gust front promote forward-surging smaller separation between mesocyclone aloft other hodograph shapes. This promotes intensification these simulations. Similar trends function orientation observed for varying shear-layer depths bulk-shear magnitudes specific shapes strong rotation may vary different deep-layer profiles or thermodynamic environments from those here; however, study concludes that positioning necessary condition supercell tornadogenesis be modulated by