• CB Clusters appear as relatively large separate cells in satellite images.
• In the IR, VIS and WV images CB Clusters are generally white, indicating thick, multi-level clouds, but in the initial phase of development separate grey cells are visible, indicating relatively low tops.
• Very often the surrounding atmosphere is characterised by the development of other convective cells.
• In well-developed situations, the cirrus shields of single CB cells merge, leading to a very white smooth cloud shield in the IR and a somewhat transparent appearance in the VIS image.

In most cases cumulonimbus clouds of considerable dimension exist within a group of smaller convective cells (see Meteorological physical background).
In the mature stage the anvils of the large CBs extend downstream from the actual cells, which appear as a transparent grey to white layer in the IR image. The satellite image shows frontal cloudiness from a dissolving Cold Front over western and northern France. In central France and in the north-eastern part of Spain convective activity is visible in two phases: an initial stage over north eastern Spain and a mature stage over central France. Both are visible in VIS. In the IR image only the mature stage is distinct. In the Water Vapour image the cluster is only visible when it is well developed, as can be seen over central France. The cluster over north eastern Spain however is hardly visible.

Appearance in AVHRR imagery

• Cb Clusters are easy to detect with AVHRR images, as the better resolution helps to see the individual cells better.
• Combination image 124 is very powerful in showing these cells. As the cells grow and the cirrus anvils spread, the intensely white cores stay identifiable within the bluish cirrus filaments.
• 124 image combinations usually give a better visual appearance than daytime 345 image combinations due to better contrast between convective areas within the cloud and surrounding cirrus clouds. Cb Clusters are also very striking in 345 image combinations due to strong contrast between white clouds and dark red cloud-free land areas.

In the satellite images numerous separate well developed Cb cells are located over western Russia, White Russia and Ukraine (the northwestern corner of the Black Sea is located in the bottom right corner of each image, while Estonia is located in the top left corner).

The Cb cells can easily be identified as being mainly separate clouds systems. Some merging of the clouds is taking place just northwest of the Black Sea. The NOAA 124 images show the thick Cb cores within the surrounding bluish cirrus anvils. At the same time the Cb cells in the NOAA 345 images are very distinct white in otherwise reddish surroundings, but the details are partly lost due to the saturated whiteness everywhere within the cells.

Similar differences can also be seen in the individual VIS and IR images.