When I saw this vast, rolling structure whose summits seemed to reach the boundaries of the earth’s atmosphere, I knew I was almost surely looking at a cumulonimbus calvus, the next stage of development of the large cumulus congestus clouds I’ve been photographing.

As the congestus clouds build and swell, their tops begin to lose the clearly defined “cauliflower” look, becoming smoother, high, and more consolidated.

This is a big deal; it is the moment when the cumulus congestus becomes a cumulonimbus calvus.

This term derives from the Latin word for “bald.

The moment of transition is reflected in the photo above, the big cloud is still growing as indicated by the bulging protuberances and the blue sky breaking through above it, showing plenty of solar power still feeding the growth.

I am getting this weird feeling that the clouds are talking to me now. The next step is to start talking back.