Bulk Microphysics of Mesoscale Convective Systems Inferred from Polarimetric Radar Observations

In 2013, the fleet of NEXRAD WSR-88D’s were upgraded to dual-polarization capabilities. This was a major revolution within the radar meteorology community which has been beneficial to both operational and research meteorologists. Unlike conventional single-polarization radar, dual-polarization allows for the identification of particle shape, size, orientation, and concentration within a sample volume due to the addition of new radar variables, specifically differential reflectivity (Z_DR), specific differential phase (K_DP), and the co-polar correlation coefficient (⍴_HV).

Traditionally, single case analyses have been the primary method of examining microphysical processes within precipitating systems. While these studies can provide insight into specific storms, they do not indicate if their results are robust features of all storms. In this study, we seek to leverage high-resolution polarimetric radar observations to understand the bulk microphysics and hydrometeor distributions within mesoscale convective systems (MCSs). We focus on using a large number of MCS events to examine hydrometeor distribution changes in relation to storm lifecycle, storm structure, storm environment, geographic location, and time of year. Secondly, we also make comparisons between observed hydrometeor characteristics and simulated polarimetric observations from an idealized model and identify how we can improve radar-based hydrometeor classification from these comparisons.