When a cumulus grows into bigger clouds with large vertical extension, its name changes to cumulonimbus calvus or towering cumulus (see special Towering cumulus page). These can be found on very high altitudes and if it develops even more it will turn into a cumulonimbus capillatus. Massive cumulus clouds can be very beautiful, like here on 10000 metres.

Here the convective movement has built up the probable humilis and congestus clouds into a calvus cloud. If it continues to grow in the right hand portion it could turn into a capillatus cloud.

This cool cloud shows the beginning of the formation capillatus with its horizontal extension at the top of the cloud. Very fuzzy and soft it still looks like a 'kind' cloud.

Beautiful 'cauliflower' formations on high altitude, around 10000 metres.

Above this tropical turquoise blue water a system is building up. Still in the calvus stage but most likely to develop in to a massive thunderstorm with precipitation.

How about this nice formation where the top is sun lit. On ground it's already night time.

This awesome tropical cloud looks like it's growing from the ocean. Well, it basically is, growing into incredible heights. In the dark portion to the left it's raining, to the right the weather is fair. This shows how quickly weather can change in the tropics.

An apparent hazy day on ground but with plenty of calvus clouds in the area. These clouds will not yet give any precipitation.

Just before sunset the pinkish colour is visible on this calvus top at 10000 metres.

Beautiful moments at sunset.

One build-up over the sea between China and the Philippines.

A beautiful and massive isolated calvus cloud.