photo #6336111

While on a bike ride in San Diego, California, US, David Bahr (Member 62,247) saw a dazzling display of Altocumulus cloudlets covering the whole sky above – and the sky below, for that matter, as they reflected in the rippling waters of Lake Murray. When Altocumulus dominates most of the sky like this, we define it as the cloud species stratiformis. This Altocumulus stratiformis also has gaps between its cloudlets, a form known as perlucidus, is arranged into rows, called undulatus, which appear to fan out from the horizon, known as radiatus. Perlucidus, undulatus, and radiatus are all varieties of Altocumulus. A cloud can be classified as more than one variety at a time. You can just add the terms as appropriate. Seems about right that a sky as expansive and dazzling as David’s should have an over-the-top name like Altocumulus stratiformis perlucidus undulatus radiatus.