What causes this perfect circle of clouds ?

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1 Answer
Apr 1, 2018

That is not a circle of clouds.

Explanation:

You are looking at weather radar which is looking at liquid or soild water, however radar is not sensitive enough to pick up cloud droplets. What you are looking at there is precipitation. This might not be the precipitation that is reaching the surface of the Earth but precipitation in the cloud. The clouds are going to cover much more area.

That being said, the main question is why is it a perfect circle? The answer is because that is the range of the radar. The precipitation doesn't necessarily end at that point, it is simply the point that the radar beam ends. That is why it is a perfect circle.