Dark gray and flat or really dark almost black and puffy
A tornado
The name given to a towering cloud that has not fully developed into a thunderstorm is a cumulus congestus cloud. These clouds are large, puffy clouds with vertical growth, indicating instability in the atmosphere.
A wall cloud is a large lowering of a rain free cloud base often associated with the rotating updraft of a thunderstorm known as a mesocyclone.
A wall cloud is a large, lowering cloud formation that extends beneath the base of a thunderstorm. It often has a wall-like appearance and can be rotating. Wall clouds are typically dark and turbulent, and can sometimes be a precursor to tornado formation.
The transformation from a thunderstorm cloud to a tornado can occur rapidly, typically within a matter of minutes. This process involves the development of a severe thunderstorm with rotation that can quickly strengthen and produce a tornado.
black and gray
cumulonimbus
The entire thunderstorm is a cumulonimbus cloud.
It is like a gray cloud all over the city
Cumulonimbus
A cumulonimbus cloud/thunderstorm cloud
by cloud
Communolimbus
A thunderstorm cloud is a type of rain cloud that produces thunder and lightning due to the presence of strong updrafts and downdrafts within the cloud. While rain clouds can produce precipitation in the form of rain, they do not necessarily have the same intense vertical movement and electrical activity as thunderstorm clouds.
cumulonimbus cloud
It is a thunderstorm.
A shelf cloud is produce by thunderstorm outflow, resulting from rain cooled air being force downward and outward in a thunderstorm. A shelf cloud may indicate that strong straight-line winds are coming A wall cloud is found in the mesocyclone, or rotating updraft of a type of thunderstorm called a supercell. This is an indicator that a tornado may soon form.