A few days ago, we received this incredible picture from Ann Connolly showing a pretty cool cloud formation over the Great Sacandaga Lake:
Of course she wanted to know… what type of cloud is that?!?
We think it’s a cumulus congestus, which is actually a fairly common type of cloud. The picture, however, still impressive! This just happens to be an incredible shot of an unusually symmetrical example. Let’s break down what the name means…
Your basic, puffy white cloud is called cumulus humilis . They form via convection, meaning the ground heats up and warms the air closest to the surface of the earth. That air becomes more buoyant and rises. At a certain height, if conditions are right, the water vapor in the air condenses into droplets and forms a cloud.
If there’s enough rising air, the cloud can begin to look a little more impressive. It’ll grow vertically into what we call cumulus congestus. These can begin to produce rain, as well.
Now if there’s even more rising air, the cloud can grow even taller. This can continue until the top of the cloud reaches a level called the tropopause. In most cases, that is as high as it can go.
The rising air then spreads outwards instead of upwards, forming a classic “anvil” shape. This stage is called cumulonimbus, and it’s the classic thunderstorm cloud.
In conclusion: Ann captured a spectacular example of cumulus congestus on camera. They are the stage in-between a fair-weather cumulus cloud and an intense thunderstorm. While they form all the time in the summer, it’s not often that they look as spectacular as this one.
Thanks for sharing, Ann!