Cumulonimbus incus

Cumulonimbus incus
A cumulonimbus incus cloud, showing the characteristic anvil-top shape the cloud type displays
Abbreviation	Cb inc.
Genus	Cumulonimbus (heap, cloud/severe rain)
Species	Capillatus (fibrous)
Appearance	Large flat-top cloud
Precipitation cloud?	Yes, often intense

A cumulonimbus incus (Latin incus, "anvil") also known as an anvil cloud is a cumulonimbus cloud which has reached the level of stratospheric stability and has formed the characteristic flat, anvil-top shape. It signifies the thunderstorm in its mature stage, succeeding the cumulonimbus calvus stage. Cumulonimbus incus is a sub-form of Cumulonimbus capillatus.

Hazards

A cumulonimbus incus is a mature thunderstorm cloud generating many dangerous elements.

• Lightning; this storm cloud is capable of producing bursts of cloud to ground lightning.
• Hail; hailstones may fall from this cloud if it's a highly unstable environment (which favors a more vigorous storm updraft).
• Heavy rain; this cloud may drop several inches of rain in a short amount of time. This can cause flash flooding
• Strong wind; gale-force winds from a downburst may occur under this cloud.
• Tornadoes; in severe cases (most commonly with supercells), it can produce tornadoes.

Classification

Cumulonimbus clouds can be powerful. If the correct atmospheric conditions are met, they can grow into a supercell storm. This cloud may be a single-cell thunderstorm or one cell in a multicellular thunderstorm. They are capable of producing severe storm conditions for a short amount of time.