Circumzenithal ArcAugust 16th, 2013 at 12:43 am by Bill Steffen under Bill's Blog, Weather
Check out this picture from Skywarn Storm Spotter Erin Wiseman-Parkin. Click on the picture to enlarge. Erin took this picture on August 4th in Cutlerville. This is a wonderful picture of a circumzenithal arc, a variety of halo. It’s not a rainbow (which you see when the sun is at your back). With a circumzenithal arc, you are facing more towards the sun. It’s in the shape of a smile or grin. The red color (longest wavelength) is on the outside of the arc. Sunlight (made of the 7 primary colors) is passing through the hexagon-shaped (6-sided) ice crystals of the cirrus clouds. This picture is special because of the interaction with the ice crystals of the cirrus clouds, giving the shape of the bird or angel. Here’s more pics. of circumzenithal arcs from google images.