I was browsing online looking for some images and I came across this picture from Upshot Knothole-Anne. This shot took place in the NPG I believe north of Las Vegas.
If you notice on the left there are columns of vapor rising skyward and from certain "fixed" positions on the desert floor. I would say tanks but I am not sure. This would happen to be my question. The detonation is only a few seconds into the mushroom cloud, the cloud hasnt even developed yet, and these smoke pillars are allready at the max heighth of the mushroom clouds top altitude. These pillars from vaporized paint on these vehicles or just anomolies? I havent seen anything like this in any other shot Ive seen.

The regular pattern of those smoke lines indicate they are no natural phenomenon In fact these are just that, smoke lines generated by a bunch of smoke missiles before the detonation to visualize the shockwave and how it spreads out.

IMO those cannot be vapour columns, as they are very constricted, and there is no deflection from the vertical (which should be there due to the shockwaves). They Dont look like photographic anomolies either.

Have not seen anything like this before.

they would have to be pretty huge smoke missles because you can see the launch points from the columns closest to the center of the picture. The altitude of the streams are at least 20k feet up. For scale, this is a 16kt shot. And what really puzzles me is that if they are smoke rockets, how come the concussion didnt dissintegrate the columns?

Yes those missiles were certainly big, but it's not like nuclear tests were conducted in a minimalist approach. Don't overestimate the strength of nukes either; we are talking about an extremely powerful explosion for sure but the shockwave will still travel at a limited speed (should be speed of sound?) and thus not reach the smoke lines immediately.

Look here for similar examples:



http://www.aracnet.com/~pdxavets/tumbler2.htm

At my duty station I had a bunkmate that was in EOD, and part of his training included knowlege of a nuclear device. He told me that the shockwave travels at approximately 1000 fps on a weapon of about 24kt. I dont remember how fast it goes per larger weapons. It also has to do with the altitude of detonation and location of where it was detonated.

1000 fps is slightly less than the speed of sound at sea level.

and if it is subsonic it is not a true shockwave, the vale I am used to hearing for shockwaves is 1000mph, which is well over 760 mph for sea level Mach.