Tornado aloft is a funnel cloud.
Nope. A funnel cloud is simply an area of condensation caused by a tornado vortex lowering the pressure to the right amount to condense cloud droplets. In some tornadoes, the pressure fall is great enough (and so is the relative humidity of the air surrounding the vortex) that the condensation funnel fully condenses to the ground. In others, it does not. In either case, they are still both tornadoes.
Funnel clouds and debris clouds are accessories to tornadoes. In other words, the tornadic vortex
causes them.
As for tornadoes touching down, lifting, and skipping, please read:
http://cimms.ou.edu/~doswell/a_tornado/atornado.html
In particular:
"I want to take a moment to gripe about the word
touchdown in association with tornadoes. I believe that "touchdown" is inappropriate to describe the actual process of tornadic winds commencing at the surface. There is nothing coming down, in the sense that a solid tube would fall out of the sky. What actually goes on when a vortex is present in the atmosphere is that the vortex either (a) is already present at the surface, or (b) wraps around itself, like a smoke ring. If you find this confusing, please see my
Vorticity Primer, where this concept is described in some detail. The laws of Fluid dynamics tell us that (a) and (b) are the
only two options. As noted
elswhere [in
formal form,
here], the intense part of the vortex
can build downward, but this is not the same as a tornado descending. What is actually happening is that the vortex at the surface increases its intensity (and decreasing its scale at the same time) to tornadic proportions, eventually producing winds capable of tornadic damage ... but the vortex itself is almost certainly already in contact with the ground. Strictly speaking, "the vortex" should not be equated to "the tornado," since the vortex can be present but with non-damaging windspeeds. Prior to the commencement of damaging winds at the ground, the surface vortex is weak and spread out ... as it intensifies, the winds increase and the size of the circulation contracts. The vortex also can intensify upward (as we think happens in the tornadoes that are called "landspouts" - see below). Rather than "touchdown" I would prefer to consider the observed process of the commencement of tornadic winds at the surface to be one of "spin-up" ... I hasten to add that "up" in this context does
not imply ascent, but rather an increase of spin intensity."
"By the way, in most of my experience, tornadoes do not skip. Rather, they may weaken or intensify and thereby create gaps in the damage, but their continuity is relatively high. I have not heard a lot of storm chasers discussing how the tornadoes they observe "bounce" and "skip" across country. Gaps in the damage path can arise because (a) there is nothing to damage, or (b) the circulation has weakened to the extent that no evidence of the tornado's passage is left. Should we consider the latter to signify that the tornado "skipped" or "lifted" during an otherwise continuous track? Even more radically, would we say the cessation in damage constituted a cessation of the tornado? In many such cases, it is clear from film or video that a visible funnel and even a dust and debris whirl (albeit perhaps only small debris) is continuous even though "damage" is not occurring. In such a case, the damage path would give erroneous input to the classification of the event, often leading to the notion of "skipping" as a means of avoiding having each gap in an otherwise linear path represent a gap between individual tornadoes. "
LOL.
