A cumulonimbus incus is a cumulonimbus cloud

Cumulonimbus cloud

Cumulonimbus is a towering vertical cloud that is very tall, dense, and involved in thunderstorms and other inclement weather. Cumulonimbus originates from Latin: Cumulus "Heap" and nimbus "rain". It is a result of atmospheric instability. These clouds can form alone, in clusters, or along a cold...

 which has reached the level of stratospheric stability

Tropopause

The tropopause is the atmospheric boundary between the troposphere and the stratosphere.-Definition:Going upward from the surface, it is the point where air ceases to cool with height, and becomes almost completely dry...

 and has formed the characteristic flat, anvil

Anvil

An anvil is a basic tool, a block with a hard surface on which another object is struck. The inertia of the anvil allows the energy of the striking tool to be transferred to the work piece. In most cases the anvil is used as a forging tool...

-top shape. It can cause a supercell

Supercell

A supercell is a thunderstorm that is characterized by the presence of a mesocyclone: a deep, continuously-rotating updraft. For this reason, these storms are sometimes referred to as rotating thunderstorms...

 and then a tornado

Tornado

A tornado is a violent, dangerous, rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. They are often referred to as a twister or a cyclone, although the word cyclone is used in meteorology in a wider...

.

A cumulonimbus incus is a sub-form of cumulonimbus capillatus.

Hazards

A cumulonimbus incus is a mature thunderstorm cloud and can produce many dangerous elements.

• Lightning
  Lightning
  Lightning is an atmospheric electrostatic discharge accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms...
  
  ; this storm cloud is capable of producing bursts of cloud to ground lightning.

• Hail
  Hail
  Hail is a form of solid precipitation. It consists of balls or irregular lumps of ice, each of which is referred to as a hail stone. Hail stones on Earth consist mostly of water ice and measure between and in diameter, with the larger stones coming from severe thunderstorms...
  
  ; small hail balls may fall from this cloud.

• Heavy rain
  Rain
  Rain is liquid precipitation, as opposed to non-liquid kinds of precipitation such as snow, hail and sleet. Rain requires the presence of a thick layer of the atmosphere to have temperatures above the melting point of water near and above the Earth's surface...
  
  ; the cloud may drop several inches of rain in a short amount of time. This could cause flash flood
  Flash flood
  A flash flood is a rapid flooding of geomorphic low-lying areas—washes, rivers, dry lakes and basins. It may be caused by heavy rain associated with a storm, hurricane, or tropical storm or meltwater from ice or snow flowing over ice sheets or snowfields...
  
  ing

• Strong wind
  Wind
  Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space...
  
  ; gale force winds from a downburst
  Downburst
  A downburst is created by an area of significantly rain-cooled air that, after reaching ground level, spreads out in all directions producing strong winds. Unlike winds in a tornado, winds in a downburst are directed outwards from the point where it hits land or water...
  
  may occur under this cloud.

Classification

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

External links

• Picture of a fully developed Cb inc