On Thursday, 12 November 2015 15:15:07 UTC+2, Chris Rollings wrote:
We have a bit of an advantage in the UK in that cloud flying is permitted
and that makes it a lot easier to get into thermal wave. I've done quite a
lot of it over the last 45 years. I've also discussed it with both Joachim
and Tom. My experience is that very weak (reduced sink usually) wave,
close the the up-wind side of the cumulus top, is there more often than
not. It might even be more accurate to call this "cumulus ridge lift".
Classic streets with upper wind, immediately above the inversion, at a
significant angle to this (doesn't have to be 90 degrees, 60 or so will
do), producing good usable wave (best I've ever seen was about 8 knots), is
quite rare in the UK but I've experienced a fair number over the years.

I've done it also, both before starting cloud flying and after. It is quite rare and lift is usually extremely weak. I remember some notable cases with approaching front and strong wind shear.

I wouldn't call it ridge lift BTW, at least if term means same as anabatic slope wind. They are purely thermally forced, which is completely different phenomenom.