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:
“Once more unto the breach, dear friends, once more,
Or close the wall up with our English dead.
In peace there’s nothing so becomes a man
As modest stillness and humility,
But when the blast of war blows in our ears,
Then imitate the action of the tiger.
Stiffen the sinews, conjure up the blood,
Disguise fair nature with hard-favoured rage.”
—William Shakespeare (1564–1616)
“These boys who love their mother
who loves men, who passes on
her sons to other women;
The cloud across the sky. The windy pines.
the trickle gurgle in the swampy meadow
this is our body.”
—Gary Snyder (b. 1930)