How big are cumulus clouds

Cumulus - heap cloud or cumulus cloud

The cumulus cloud is the typical heap or cumulus cloud - mostly at an altitude of 600 to 2000 meters.

It has a smooth horizontal cloud base and usually has its own shadow, i.e. the cloud base is visibly slightly darkened. Above that one finds the white, cauliflower-like swellings that are sharply raised against the background. Cumulus clouds are expediently divided into three subclasses according to their vertical extent:

Cumulus humulis (humilis = Latin: flat, low):
A cumulus cloud with a small vertical extent

These flat cumulus humilis clouds are not the typical summer cumuli that form due to local overheating, but rather cumuli that were able to form in a moist, unstable layered cold air mass on an evening in December 2000.


Cumulus mediocris (mediocris = lat. moderate, mediocre):
Correspondingly, a cumulus cloud of medium vertical extent

This picture shows a Cumulus mediocris viewed from an airplane. The clouds can be viewed particularly well from high-flying jets, as air pollution is many times lower at high altitudes than in the lowest kilometer of the earth's atmosphere. The picture was taken in 1997 on a flight to the sunny island of Mallorca.

Cumulus congestus (congestus = Latin: massive, strong):

A cumulus cloud with an even greater vertical extent, the upper limit of which extends far into the medium-high area. Since the top of the cloud consists mainly of water droplets and not ice crystals, its edges are sharply defined everywhere.


With the kind support and approval of: Dipl. Met. Björn Beyer
Photos: Dipl. Met. Björn Beyer