Scud (cloud)

Pannus
Scud clouds in a thunderstorm.
Abbreviation	Scud/Pan
Symbol
Genus	Altostratus, Nimbostratus, Cumulus, Cumulonimbus
Altitude	200-16,000 m (1,000-52,000 ft)
Classification	Family D (Vertically developed)
Appearance	Ragged frazzles, scud
Precipitation	no, but appears under precipitating clouds.

Pannus,^[1] or scud clouds,^[2] is a type of fractus cloud at low height above ground, detached, and of irregular form, found beneath nimbostratus, cumulonimbus, altostratus and cumulus clouds. These clouds are often ragged or wispy in appearance. When caught in the outflow (downdraft) beneath a thunderstorm, scud clouds will often move faster than the storm clouds themselves. If the parent cloud that scud clouds pair with were to suddenly dissipate, the pannus cloud accessory would not be able to be told apart from a fractus cloud formation.

When in an inflow (updraft) area, scud clouds tend to rise and may exhibit lateral movement ranging from very little to substantial.