I find the stationary clouds over hills easy to understand, because the fall and rise in the air temp happens purely as a result of the air flowing up the hill and then down the hill.
What I find more suprising is how fog can dissipate so markedly after passing over just say 100-200m of the land, in onshore wind of say 10-20kt.
In just some tens of seconds, the air must be warming up by a few degrees, and it can only be from radiation from the ground. It cannot be conduction.