Utilizing differential reflectivity (ZDR) data from the WSR-88D radar in State College, Pennsylvania (KCCX), CBL depth and entrainment zone (EZ) properties are investigated across 30 days starting in summer 2022. These signals are compared to atmospheric observations collected by Windsond weather balloons launched from The Pennsylvania State University, University Park campus. Preliminary results confirm that the minima in quasi-vertical profiles (QVPs) of ZDR values during the daytime correlate well with Windsond-observed CBL depths. It is also found that QVPs of azimuthal variance of ZDR can provide further information on CBL and EZ characteristics, especially when the ZDR signal alone is unclear. Exploration of a large number of QVPs identifies several characteristic structures for the minimum ZDR channel that tracks the diurnal evolution of CBL top: narrow channels, wide channels, and uncapped channels. These ZDR and ZDR variance channel structures are investigated using both surface and Windsond observations, as well as simple CBL parameterizations to investigate the physical processes that lead to their formation.

