For the first time I have seen a mirage in the fog. It was like a heat haze mirage you might see on a road on a hot day. At first I thought my eyes were faulty. But the fog was being lightly blown by the wind. But the density of the fog changed from patch to patch. As the fog passed the tree on the other side of the road, the diffraction of the fog changed. The tree looked like it was suffering from a cheap horror movie effect.