Numerical simulations of supercells in convective boundary layers

Previous numerical simulations of supercells, completed within horizontally homogeneous environments, have successfully elucidated the dynamics responsible for their formation and evolution. Supercells in nature, however, are initiated and evolve in environments often characterized by a well-developed convective boundary layer (CBL) with marked observed horizontal variations in vertical wind shear as well as sensible heat and moisture fluxes. Yet unknown is the role these heterogeneities play in the morphology of supercells, and how supercells themselves alter the CBL.

The Advanced Regional Prediction System is employed to simulate a supercell within a well-developed CBL whereby coherent structures, such as horizontal convective rolls, interact and evolve with a supercell from its inception as a developing convective cell. Preliminary results indicating the effects of a highly variable CBL on deep, moist convection are presented.