A wall cloud (or pedestal cloud) is a large, lowering cloud formation that develops beneath the base of a cumulonimbus cloud that often forms tornadoes. It is typically beneath the rain-free base (RFB) portion of a thunderstorm, and indicates the area of the strongest updraft within a storm. Wall clouds are sometimes an indication of a rotating mesocyclone in a thunderstorm, and most strong tornadoes form from wall clouds. However, wall clouds do not always rotate.
Read more about Wall Cloud: Genesis, Structure, Supercell and Tornado Significance
Famous quotes containing the words wall and/or cloud:
“What harm cause not those huge draughts or pictures which wanton youth with chalk or coals draw in each passage, wall or stairs of our great houses, whence a cruel contempt of our natural store is bred in them?”
—Michel de Montaigne (1533–1592)
“When the lamp is shattered,
The light in the dust lies dead;
When the cloud is scattered,
The rainbow’s glory is shed;
When the lute is broken,
Sweet tones are remembered not;
When the lips have spoken,
Loved accents are soon forgot.”
—Percy Bysshe Shelley (1792–1822)