A small-scale, persistent lowering from the rain-free base of a thunderstorm, particularly of a supercell thunderstorm, and normally found on the inflow side of the storm (to south or south-west, in the northern hemisphere). Wall clouds range between 1 and 8 km in diameter and often display rapid upward motion. In addition, some exhibit cyclonic rotation, and these often develop into tornadoes. Also known as a lowering. The term is occasionally used instead of eye wall.
Subjects: Meteorology and Climatology.