Term

cumulonimbus

Daniel MarkFounder & Editor, Aviatopia
Published Mar 1, 2026Updated Mar 1, 20261 min read

A towering, anvil-shaped cloud associated with thunderstorms — producing severe turbulence, lightning, hail, heavy precipitation, and wind shear.

aviation-glossary

Quick Facts

Type
Cloud Type
Definition
A towering, anvil-shaped cloud associated with thunderstorms
Used By
Pilots, Dispatchers

Definition#

Cumulonimbus (CB) is a dense, towering vertical cloud extending from low levels to the tropopause or beyond, associated with thunderstorms. It produces heavy rain, lightning, hail, severe turbulence, wind shear, and potentially tornadoes.

Why It Matters Operationally#

Pilots are trained to avoid cumulonimbus by at least 20 nautical miles laterally. METARs encode CB presence, and SIGMETs may be issued for embedded or squall-line CB activity.

See Also

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