A Polarimetric and Microphysical Analysis of the Stratiform Rain Region of MCSs

Models often struggle resolving the stratiform region behind the main convective line in mesoscale convective systems (MCSs), an issue often attributed to deficient microphysical parameterizations in models. Increasing in situ observations of such stratiform precipitation is crucial to improving model parameterizations, and connecting such in situ measurements with ground based radar observations has the potential to improve understanding of how various polarimetric fingerprints in the stratiform region are to be interpreted, especially if it can be done using operational radar data and without needing special radar scans. In this study, in situ microphysical data collected during both the Midlatitude Continental Convective Clouds Experiment (MC3E) and Plains Elevated Convection at Night (PECAN) are compared with operational WSR-88D radar data, using a novel column vertical profile (CVP) technique. Such CVPs are made by taking data collected using traditional volume scans—such as are done by WSR-88D radars—and averaging and interpolating the data such that they are displayed in a time-height format. Similar to quasi-vertical profiles (QVPs), CVPs are unique in that they are representative not of the entire distance in range and 360° in azimuth around a radar, but of only a sector of set size in range and azimuth, facilitating more exact comparison of radar data to microphysical data. Data of particular interest collected by in situ probes include particle habits, number concentration, and ice water content, which could lend insight into the causes of various polarimetric fingerprints seen in both QVPs and CVPs.