Altostratus is a middle-altitude cloud genus made up of water droplets, ice crystals, or a mixture of the two. Altostratus clouds are formed when large...

The altostratus undulatus is a type of altostratus cloud with signature undulations within it. These undulations may be visible (usually as "wavy bases")...

Opacity-based varieties Altostratus translucidus (V-49) Altostratus through which the sun can be seen. Altostratus opacus (V-50) Altostratus that completely blocks...

precipitation that evaporates before reaching the ground. Genus altostratus (As) – Altostratus is a midlevel opaque or translucent nonconvective veil of gray/blue-gray...

front, where the altostratus is starting to fragment, resulting in patches of altocumulus perlucidus between the areas of altostratus. Altocumulus is also...

preceded by higher-level clouds such as cirrostratus and altostratus. Often, when an altostratus cloud thickens and descends into lower altitudes, it will...

detached, and of irregular form, found beneath nimbostratus, cumulonimbus, altostratus and cumulus clouds. These clouds are often ragged or wispy in appearance...

sheen in the sky or as a striated sheet. They are sometimes similar to altostratus and are distinguishable from the latter because the Sun or Moon is always...

away. A thickening and lowering of these high clouds into middle-stage altostratus or altocumulus is a good sign the warm front or low has moved closer...

stability and wind shear. As the front approaches, middle-étage gives way to altostratus and low-level stratocumulus with intermittent light precipitation if...