“What is an anvil cloud?”
Hedrick Middle School
An anvil cloud forms from a strong updraft with enough moisture to form a cloud that builds to the tropopause. The layer of the atmosphere above the troposphere is the stratosphere and has warmer air than the troposphere. So when a cloud builds and is able to reach the tropopause the stratosphere acts like a ceiling preventing the cloud from building any more vertically so the cloud spread horizontally forming what looks like an anvil. If you have a strong enough updraft you can get an overshooting top which is able to pop through the tropopause into the stratosphere.