I saw the beauty queen on TV tonight. So sad!
The sheep thing is wrong but darn funny!
The tornado is scary. I think Brian is right. Actually, there has to be a continuous updraft first that creates rotation. Then there's some kind of downdraft/wind shear that brings the rotation to the ground. I'm not sure if the updraft means that the tornado actually starts at the ground. It's probably not a tornado at that point (just rotating upwardly moving air), so technically probably not. Right? Not till the downdraft pushes the rotation to the ground is it considered a tornado.
Well, here, this explains it as best as they can right now:
Many aspects of the tornadogenesis process are poorly understood, if at all. However, based on our limited observations, especially those obtained in VORTEX and subsequent efforts, we have begun to see some common processes occurring. These are briefly summarized here so that we can attempt to relate them to things that can be observed and forecast at scales larger than the storm.
The first step in tornadogenesis is the development of a rotating updraft. We believe this can occur on a variety of scales, from the typical radar-observed “mesocyclone†that occurs on a scale of several kilometers, down to scales closer to that of a tornado itself and not readily observed on Doppler radar, except at very close range. At this stage, we have rotation aloft… a precursor of tornado formation (although it sometimes is there only a few minutes before a tornado forms!).
Then, a downdraft must develop within the rotating column of air. It seems that this downdraft is usually at the upshear periphery of the mesocyclone. There is no other way to get rotation to the ground (except through turbulent diffusion of rotation from aloft which is a highly unlikely process). The details of how this downdraft is thought to transport rotation toward the ground are left to another page*. Not only does the downdraft bring the rotation downward, there is good evidence that in some cases it actually intensifies the overall mesocyclone as well. At this stage, we now have rotation extending to the ground, but we do not yet have a tornado.
In the third stage, some of the downdraft air that descends in the outer portion of the rotating region spreads upon reaching the ground. It may spread inward toward the axis of rotation, as well as outward away from the axis. To the extent that the inward-spreading air contains buoyancy, CAPE, and does not contain CIN, it can then accelerate upward near the axis of rotation. The associated convergence and stretching leads to the development of a tornado.
As for videos, I've got nothing.
Lali