Llyn y Fan Fawr - more foam rays

I posted recently about lines of foam forming on Hayeswater perpendicular to the wavefronts and thus effectively acting as rays. Here it is again, this time from the Black Mountain in South Wales. Again the wind was driving briskly down the length of the lake from left to right. It rucks the water up into waves perpendicular to the wind direction but the foam lines up with the wind direction. I'm trying to come up with a theory as to why.