Stratiformis is a species of cloud, which you can think of as like a pattern or characteristic of one of the main cloud types, or genera. It is associated with the three genera that take the form of clumpy layers: the low-level Stratocumulus, mid-level Altocumulus, and high-level Cirrocumulus. We add the stratiformis term after any of these formations when the layer of clumps, known as cloudlets, extends over most, if not all, of the visible sky.

These clouds spotted by Steve Fiano (Member 45,493) as the Sun rose over Danzante Bay, Loreto, Mexico look to be mid-level ones. This would make them Altocumulus stratiformis. ‘In the space of three minutes, the clouds went from deep blue, to red, to gold, to gray,’ said Steve. ‘Out in the south Baja town of Loreto, I saw the gold dust that faded away.’