These studies consistently identified convective generating cells and precipitation fall streaks at the top of otherwise stratiform warm frontal and comma head clouds (Browne 1952; Marshall 1953; Gunn et al.
The billowed reflectivity pattern, together with the lack of fall streaks emanating from the updrafts, suggests that shear near cloud top was mixing particles within the cloud-top layer.
Fall streaks emanated from the base of the wave layer and merged above the bright band.