To first order, the wind pressure is proportional to the air density,
so altitude should have some effect. I haven't looked up the relationship
between pressure and density, but it seems they should be proportional
at equilibrium, so the wind pressure should be roughly proportional to
the air pressure.
However, a problem I've been interested in for some time is, what about
the density of air plus rain during a storm? It seems that the density
of the wind-blown water must count for something, especially in heavy
squalls. This hasn't come to the top of my list, but I would guess this
is a source of additional antenna forces that can't be ignored.
Sorry I don't have a more elegant answer re altitude, but the expression
for wind force is first order in air density for sure.
73 de Dave, W6QHS
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