high density of ice crystals & columnar ascents in Cb
Hi there,
The following article may be of interest:
SKYbrary - High Level Ice Crystal Icing This one can give clues about ice crystals observed (or not) by conventional E.M. weather onboard radars like the ones on airliners and by several Lidars
AMS Online Journals - Studying Altocumulus with Ice Virga Using Ground-Based Active and Passive Remote Sensors Seems that these dry crystals are difficult to detect using E.M. radars.
Jeff