Fog in Danby Dale

We set off from Home in sunshine and ran into a thick Fog on the high moor, coming out of it at the junction for Botton where I took this shot of the Fog pouring down into the valley and being held back by the warmer air coming up from the sunlit valley bottom.
Passing there again after lunch the fog had hardly moved to the North and was being swept across the end of the Valley by a West Wind, and the little farm was still seeing some sunshine.
But up on Blakey Ridge the visibility was down to about 100 yards.