Virga appear with most species of Altocumulus. Altocumulus floccus frequently dissipates, leaving very white trails of ice crystal virga. If the Altocumulus floccus completely dissipates, the virga is identified as Cirrus altocumulogenitus.
Mamma, cavum, fluctus and asperitas are sometimes visible in Altocumulus.
The text enclosed in grey-shaded boxes, like this example, comprises Annex I to the Technical Regulations (WMO-No. 49) and has the legal status of standard practices and procedures.