List of cloud types
Clouds of the genus stratus form in low horizontal layers having a ragged or uniform base. Ragged stratus often forms in precipitation while more uniform stratus forms in maritime or other moist stable air mass conditions. The latter often produces drizzle. Stratus that touches the Earth's surface is given the common name, fog, rather than a Latin name that applies only to clouds that form and remain aloft in the troposphere."Cloud types are sorted in alphabetical order except where noted".
The division of genus types into species is as shown in the following table. The species are sorted from left to right in approximate ascending order of instability or vertical extent. The genus types are arranged from top to bottom in the same ascending order of instability within each étage. (1)=Stratiform types, (2)=Cirriform types, (3)=Stratocumuliform types, (4)=Cumuliform types, (5)=Cumulonimbiform types.
Vert=Vertical or multi-level, MV=Moderate or deep vertical, TV=Towering vertical.
Cloud physics
Cumuliform and cumulonimbiform heaps and deep stratiform layers often occupy at least two tropospheric levels, and the largest or deepest of these can occupy all three levels. They may be classified as low or mid-level, but are also commonly classified or characterized as vertical or multi-level. Nimbostratus clouds are stratiform layers with sufficient vertical extent to produce significant precipitation. Towering cumulus (species congestus), and cumulonimbus may form anywhere from near the surface to intermediate heights of around 3 kilometres. Of the vertically developed clouds, the cumulonimbus type is the tallest and can virtually span the entire troposphere from a few hundred metres above the ground up to the tropopause. It is the cloud responsible for thunderstorms.