As a temperature inversion embraced the Flathead Valley this week, mirages of ghostly snow-covered buttes shimmered on the horizon above the valley clouds.
"It's a really strange feeling to look at these familiar mountains and not recognize them," Brian Schott, a Whitefish writer and photographer, said in an e-mail. "I've seen this once before but never for such a sustained period and so dramatically affecting the mountains in all directions."
Schott provided photos that he shot of the Cabinet Mountains while skiing Whitefish Mountain Resort above the inversion. Temperatures have climbed into the 40s on the mountain while remaining in the 20s below, he said.
The name for the optical illusion is the fata morgana effect, named for King Arthur's sorceress sister.
The mirage is somewhat similar to the water that appears to be shimmering in the distance on dry highways, only to disappear. Such illusions are called inferior mirages because they come from light refracted from above. Superior mirages refract images from below. The fata morgana effect is a superior image.
According to the Weather Doctor Web site, a "superior mirage forms when cold air lies beneath relatively warmer air, a condition known to meteorologists as a temperature inversion. In this condition, light rays refract, or bend, toward the colder (and denser) air - downward. This bending causes the image of the object to appear to us to be above its actual position because our brains assume the light rays have taken a straight path from the object to our eyes…
"In a Fata Morgana mirage, distant objects and features at the horizon appear as spikes, turrets or towers, objects with great vertical exaggeration rising from the surface."
The illusions are more common in the Arctic - they are called "halgerndingar" by Icelandic people - and have prompted the creation of myths.
Contact Brett French at firstname.lastname@example.org or at 657-1387.