Once Bitten, Twice Shy

So, Jean sends me this image via E-Mail (also posted at Snopes), with the following explanation:

THIS IS A FIRE RAINBOW - THE RAREST OF ALL NATURALLY OCCURRING ATMOSPHERIC PHENOMENA.

THE PICTURE WAS CAPTURED THIS WEEK ON THE IDAHO/WASHINGTON BORDER. THE EVENT LASTED ABOUT 1 HOUR

CLOUDS HAVE TO BE CIRRUS, AT LEAST 20K FEET IN THE AIR, WITH JUST THE RIGHT AMOUNT OF ICE CRYSTALS AND THE SUN HAS TO HIT THE CLOUDS AT PRECISELY 58 DEGREES.

I was quite suspicious of this E-Mail, naturally, because I had never heard of 58 degrees being associated with anything in the sky.

Snopes says it’s OK, though, although Snopes does post false material on occasion, on purpose, in order to keep its readers on their toes, as I learned to my great chagrin last year regarding the 'Poseidon-Adventure-Silent-Movie-Shown-On-The-Titanic' false legend.

More importantly, the real authority, Robert Greenler’s “Rainbows, Halos, and Glories” confirms the existence of the phenomenon of the circumhorizontal arc, with the caveat being that the sun’s elevation angle has to be higher than 58 degrees (rather than the sun hitting the clouds at precisely 58 degrees). Normally, the sun wouldn’t be this high in the sky in Idaho, but it becomes a possibility near noon, near the summer solstice.