Surely most glider pilots can recall many similar cloud configurations over the years. I was seeing this sort of thing in the Cairngorms in the late 50's and in North Wales and in the Californian/ Sierras many times in the 70's and 80's. In one of the blogs there was a hint that it might be connected with, [dare I mention it???] tired old Global/Carbon/Shift/Pollution etc ad nauseam........
This must be because too many Meteorology academics have nothing better to do.......
As for the Dorset Doughnut......... Try Photoshop/Chemtrails/Crop Circles........