Multi-level cloud
Cloud that builds through the depth of the troposphere.
Multi-level — spanning several layers7
MammatusIISevere weather in the vicinity; often seen during or after thunderstorms
PyrocumulusVIIIMarks intense surface heat (wildfire or volcano); can build into storms
Crepuscular raysXVBroken cloud with a low sun; little weather significance
CumulonimbusXXVISevere weather imminent - thunderstorms, heavy precipitation, possible tornadoes
PyrocumulonimbusXXXIVAn extreme fire-driven storm - lightning, fierce gusts, even fire tornadoes
Anticrepuscular RaysXXXVIIBroken cloud with a low sun; little weather significance
Funnel Cloud & TornadoXLA severe rotating storm - destructive winds if it reaches the ground