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Citation: Daub, B. J., and N. P. Lareau, 2022: Observed Covariations in Boundary Layer and Cumulus Cloud-Layer Processes. J. Appl. Meteor. Climatol., 61, 1497-1508, https://doi.org/10.1175/JAMC-D-21-0213.1. Summary: We examine variations in boundary layer processes spanning the shallow-to-deep cumulus transition observed at the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site in Oklahoma. A large sample (236) of days are observed with a range of convective outcomes: shallow, congestus, and deep convection. Boundary layer and cloud-layer properties are measured to test the hypothesis that deep convection occurs when the strength of the boundary layer turbulence [i.e., turbulence kinetic energy (TKE)] exceeds the strength of the energy barrier [i.e., convective inhibition (CIN)] at the top of the convective boundary layer. Results show that days with deep convective clouds have weaker updrafts and lower CIN values in comparison with shallow convective outcomes. However, the significantly lower CIN values on deep convective days allow for weaker updrafts to penetrate the energy barrier. These findings support the use of the CIN/TKE framework in parameterizing convection in coarse resolution models. (POC: Brandon Daub, Brandon.Daub@colostate.edu. Funding: Atmospheric Systems Research program in the Office of Biological and Environmental Research, Office of Science, DOE.)