A Fire Rainbow over West Virginia (2021 Aug 30)
- Image Credit: Christa Harbig
Explanation: What’s happening to this cloud? Ice crystals in a distant cirrus cloud are acting like little floating prisms. Known informally as a fire rainbow for its flame-like appearance, a circumhorizontal arc appears parallel to the horizon.
For a circumhorizontal arc to be visible, the Sun must be at least 58 degrees high in a sky where cirrus clouds present below — in this case cirrus fibrates. The numerous, flat, hexagonal ice-crystals that compose the cirrus cloud must be aligned horizontally to properly refract sunlight in a collectively similar manner.
Therefore, circumhorizontal arcs are somewhat unusual to see.
The featured fire rainbow was photographed earlier this month near North Fork Mountain in West Virginia, USA.
Christa Harbig Says
Ghost Fire in the Sky…
We were on 33 today, headed to Franklin, WV, just after 1230.
Chris and I were out on a photo safari for the day. He was driving, when I glimpsed what I thought was a rainbow from the corner of my eye, and turned to look. This is what I saw….
I am not sure what its real name is… I’ve been calling it ghostfire. It was amazingly beautiful in an unearthly, bizarre sort of way.