International Cloud Atlas

International Cloud Atlas
Manual on the Observation of Clouds and Other Meteors
(WMO-No. 407)

Welcome to the official site of the World Meteorological Organization’s (WMO) International Cloud Atlas. This Atlas describes the classification system for clouds and meteorological phenomena used by all WMO Members. The classifications also describe meteorological meteors other than clouds – hydrometeors, lithometeors, photometeors, and electrometeors. Read More

Find a cloud
Hail and other
hydrometeors
Classification of clouds
Compare two clouds
Relation between
genera and species
Definitions of clouds
What cloud is that?
Photometeors
Different types
of deposits
Dust storms and
other lithometeors
Electrometeors
Observation of clouds
from aircraft
What is a
meteorological
meteor?
How to observe
clouds?
Previous Editions

Editorial note

The text enclosed in grey-shaded boxes, like this example, comprises Annex I to the Technical Regulations (WMO-No. 49) and has the legal status of standard practices and procedures.

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