This is one of the best examples of a cumulonimbus cloud that I've seen in ages. It has the full anvil shape. I looked up how tall such a cloud can be and a typical cloud might be 12km tall.
https://en.wikipedia.org/wiki/Cumulonimbus_cloud If my finger is worth one degree, the cloud subtends about 3.5 degrees. Tan(3.5) = 12km/distance to storm. That would put the storm at nearly 200km away. Conclusion: the cloud is not 12km tall. It must be a much shorter cloud.
