Melting and Shedding of Graupel and Hail. Part III: Investigation of the Role of Shed Drops as Hail Embryos in the 1 August CCOPE Severe Storm

Abstract

The 1 August severe storm during the Cooperative Convective Precipitation Experiment (CCOPE) has been analyzed making use of T-28 aircraft data, CP-2 radar data, and a particle trajectory model in conjunction with a time-averaged Doppler-derived wind field. This analysis reveals that water drops are shed from wet hailstones in this storm, and that some of them are shed in favorable locations to grow back into hailstones. A particular region of the storm is identified as the most likely source region for shed drops, and particle trajectory calculations show that hailstones grown from this region fall out in locations consistent with the reflectivity structure of the storm. Some trajectories are shown to fall back through this same region while at the same time shedding, providing new hail embryos.