Wall Clouds and Mesocyclones

Wall clouds come in a variety of shapes and sizes. They form under the thunderstorm updraft core and can develop on any flank of a precipitation core. They are typically located within a mile or two of the most intense precipitation. The most dangerous wall clouds, which are associated with mesocyclones and supercell thunderstorm updrafts (updrafts that rotate), have warm moist surface based inflow and produce obvious rapid upward motion and rotation. However, rotation may not always be large scale nor always easily observed. The area of perceived rotation may vary in size from less than a mile in diameter to more than three miles in extreme cases.  The most dangerous wall clouds undergo rapid continuous change. Some wall clouds form from a flat rain-free base after a burst of outflow and scud from the precipitation area, while others form before a significant precipitation area is visible. A few produce tornadoes but, most do not.  You should be suspicious of a storm that produces a wall cloud. Even non-rotating wall clouds often immediately precede the production of  large hail and high winds by the parent thunderstorm.

	Looking west southwest  at a wall cloud that was located South of El Dorado, Oklahoma. This wall cloud developed along the flanking line, several miles south of an HP supercell that hammered El Dorado with softball hail.   This wall cloud was associated with a doppler radar indicated tornado vortex signature (TVS) and at least baseball size hail.
	Looking west at a wall cloud near Snyder, Texas.  This wall cloud and associated classic supercell thunderstorm did not result in a visible tornado. This cloud formation is a textbook example of a BSC (Big Scary Cloud).
	These two  images are of the same storm as what appeared to be a wall cloud approached my location.  Since the storm came in at night, it was difficult to determine if the wall cloud was rotating or exhibited any rapid upward motion. This storm had produced a tornado near Emporia, Kansas earlier, but as the second image reveals, this was merely a detached skud cloud rolling along under the gust front.
	This unusual rotating wall cloud in Wyandotte County, Kansas is actually spinning the wrong direction (clockwise). It was very short lived and seemed to break itself off before an organized vortex could be formed.
	This cloud formation is a rolling gust front. It was accompanied by brief heavy winds to 78 MPH and followed by baseball size hail near Desoto, Kansas.
	This LP double wall cloud spawned twin F2 tornadoes near Newkirk, Oklahoma. Both vortices remained on the ground for over 15 minutes and traveled several miles.