I Quick question about explosions and displacement

[DarkBabylon]

Understanding waves typically don't displace atoms but momentarily and then they move back into place, my intuition tells me that if a pressure wave on a certain gas meets a slightly different gas but with a similar density, the different gas wouldn't move dramatically due to the pressure wave.
Is this correct or am I missing something (except the obvious math) which will say otherwise?

Specifically, can an explosion, such as that from a nuke, move a cloud?

 

[Drakkith]

Looking at the behavior of the smoke in the first few seconds of the following clip, I'd say "yes". Watch what happens when the blast wave hits them.



Edit: To clarify, I think the cloud would move some, but not much.