Sometimes called an upside down rainbow, circumzenithal arcs are "reverse rainbows," centered around the sky directly overhead -- the zenith.

The arcs are called reverse rainbows because the colors are the opposite of those seen in a rainbow; violet is on the inside of the arc and red is on the outside.  

As opposed to a rainbow, where sunlight is refracted through raindrops, the colors in a circumzenithal arc are refracted through of six-sided ice crystals and are typically visible when it's colder outside.

This picture was snapped over Oella at about 8:10 a.m. The arc will disappear if conditions change or once the sun reaches an altitude higher than 32 degrees. 

So go look up!