Field record · storm
Cumulonimbus storm cloud
Large vertically developed towers may spread into an anvil aloft. Thunder or lightning moves the observation into a safety context.
factscale · deepstructure · tower
How it forms
Deep convection carries moist air upward; mature thunderstorms contain liquid and frozen precipitation, strong vertical motion and charge separation that can produce lightning.
What separates it from a neighbor
Distinguished from ordinary cumulus by much greater vertical depth and thunderstorm processes.
Representation boundary
Scale cues matter: use horizon/ground reference or layered altitude bands so the vertical extent is not flattened.
Evidence boundary. This page separates a sourced formation explanation from the editorial “visual character” phrase above. A single image or casual observation may not contain enough context to classify a real phenomenon confidently.
Sources used for this record
WMO International Cloud Atlas — Definitions of cloudsinstitutional standard
Approximate cloud levels and genera.
Open source ↗NOAA NESDIS — Types of Cloudsgovernment education
Cloud appearance, composition and broad weather context.
Open source ↗National Weather Service — Understanding Lightning Sciencegovernment science and safety
Thunderstorm electrification, lightning and thunder; includes safety framing.
Open source ↗