Fire rainbows are the rarest of all naturally occurring atmospheric phenomena. For a fire rainbow to occur, cirrus clouds must be feet in the air with the precise amount of ice crystals, and the sun must hit the clouds at 58 degrees. (a/k/a Sun Doggies)
Fire rainbows are not actually rainbows and have no connection with fires. The true name for this exquisitely beautiful optical effect is “circumhorizontal arc”. The phenomenon can only be viewed under certain precise conditions: the cirrus clouds that ac
MAMMATUS clouds are most often associated with the anvil cloud & severe thunderstorms. They often extend from the base of a cumulonimbus but may also be found under altocumulus, altostratus, stratocumulus, & cirrus clouds as well as volcanic ash clouds^
IT'S A SONIC RAIN BOOM! Circumhorizon Arc (aka Fire Rainbow) - an ice halo formed by ice crystals located in cirrus clouds. Light passes through the hexagonal crystals and if seen at the right angle forms a rainbow cloud.