What are winter rainbows or snowbows?
In the winter, the sky is filled with brilliantly coloured optical phenomena including haloes, light pillars, arcs, spots, patches, and coloured circles. During this season, these luminous arcs in the sky, rainbow-tinted halos, and sundogs are often confused with rainbows. A halo results from the refraction of sunlight by ice crystals. Most halos, except for a few rare varieties, are seen surrounding or otherwise near the source of light such as the sun, the moon or a streetlight.
