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:
“When all this is over, you know what I’m going to do? I’m gonna get married, gonna have about six kids. I’ll line ‘em up against the wall and tell them what it was like here in Burma. If they don’t cry, I’ll beat the hell out of ‘em.”
—Samuel Fuller, U.S. screenwriter, and Milton Sperling. Samuel Fuller. Barney, Merrill’s Marauders (1962)
“Perhaps I stand now on the eve of a new life, shall watch the sun rise and disappear behind a black cloud extending out into a grey sky cover. I shall not be deceived by its glory. If it is to be so, there is work and the influence that work brings, but not happiness. Am I strong enough to face that?”
—Beatrice Potter Webb (1858–1943)