The sky over the Pinnacles National Park in California was lit by a “fiery rainbow”. This rare weather phenomenon is formed when light, passing through cirrus clouds, is refracted through flat ice crystals. The rays enter through the vertical side wall of the hexagonal crystal, leaving the lower horizontal side. This scheme provides a spectral separation of colors, which, like a rainbow, “ignite” a pinnate cloud.
Crystals should be oriented strictly horizontally, and the Sun should be above 58 degrees above the horizon. The phenomenon can not be observed from the surface of the earth to the north of 55 ° N. w. and to the south of 55 ° S. because so high the sun does not rise there (this can only be compensated by climbing a mountain). The combination of all these conditions makes the phenomenon extremely rare.
Recently, an amateur athlete who jogged in the Pinnakels Park, photographed a near-arcuate arc and sent pictures to the US National Weather Service.
Look at the misty rainbow.