An easier, simpler, and much older technique for simulating volumetric bodies (in this case, clouds) is to use multiple transparent layers of geometry. The nodal texture editor makes this effect all the more convenient, and can give surprisingly good results!

Lightwave includes a vortex distortion plugin, but unfortunately it’s a clumsy setup and especially difficult to use with other displacements. Here’s how to create the effect using nodes, and take it beyond the simple vortex.