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“What is an Anvil Cloud?”
Alexander Lopez – Eagle Point
Anvil clouds, also known as “Cumulonimbus Incus” are a very common concurrence when thunderstorms are present. When cumulus clouds start growing and expanding, updrafts in the storm continue pushing the cloud particles into the upper atmosphere. At this point, winds begin to spread these particles around.
Something called wind shear is what causes the anvil shape. Wind shear is the changing of winds with height. Friction from topography at the surface causes winds to move slower than winds in the upper atmosphere. Therefore when the clouds grow tall enough to get affected by the faster winds, spreading occurs. This is what gives the cloud it’s anvil shape.