A beautiful vision in the sky awaited the residents of the lovely settlement Isle of Palms in South Carolina several weeks ago. On an August Sunday they managed to see the phenomena called ‘fire rainbow’ – a colorful twisted cloud, which appeared in the sky and stayed there for an hour. The experts say that the technical term used for such event is called circumhorizontal arcs. These arcs appear in high-level cirrus clouds which are made up of tiny ice crystals.
The meteorologist Justin Lock stated that “In order to produce the rainbow colors the sun’s rays must enter the ice crystals at a precise angle to give the prism effect of the color spectrum”. In order for that to happen, the sun must be at an altitude of at least 58 degrees above the horizon.