At 00:56 08 April 2016, BobW wrote:
If there's genyoowine rotor upwind of "your wave
generating feature" it's coming from another, upstream, feature.

If you sail close in to a headland in tidal waters you could well find
eddies in front of the headland. Sort of 'under' the general flow.

Flying a ridge over a quarry filled with water in high winds I have seen
'cats paws' banging on the water. This is surely a rotor effect upwind of
the ridge just like the eddies seen above. I would not, however want to try
to soar on them!

Jim