About Cloud Classifications

Clouds are officially classified according to a ‘Linnean’ system, which uses Latin terms, like the systems used for naming plants and animals. The terms are based on the cloud heights and their appearance.

Most clouds fall into one of the ten main groups, known as ‘genera’. You can see the cloud genera by clicking ‘The Main Types’ button at the top of the page. Most of these main types of cloud are divided into ’species’. Many clouds can also be described in terms of one or more possible ‘varieties’. A cloud can only be of one species at a time, but can be of more than one variety. You can see what some of the many species and varieties look like by clicking on the ‘Species & Varieties’ button at the top of the page.

The table here shows all the official classification terms, and how they can be combined. (We know this would be better as a ‘clickable’ table, and we’ll try and give it links at some point.)

As an example, the cloud shown below is described as ‘Altocumulus stratiformis perlucidus’.

This is because it is of the genus Altocumulus (which means a mid-level cloud, usually composed of a layer of clumps, or cloudlets), it is of the species stratiformis (which means it stretches over most of the sky) and it is of the variety perlucidus (which means there are gaps between the clumps of cloud).

Accessory clouds and supplementary features are distinctive cloud elements that can be seen attached to, or near to, the clouds in the main groups. You can see what these look like by clicking the ‘Accessory Clouds & Supplementary Features’ button at the top of the page.

Those cloud formations and names that don’t easily fit within the official naming system are found by clicking the ‘Other Clouds’ button at the top of the page.