Why don’t we see a snowbow as we might see a rainbow?

Dear Tom,
Last month snow was lightly falling and its beauty was glittering in bright sunlight‎. Why don’t we see a snowbow as we might see a rainbow?

Emma Gates
Oak Park

Dear Emma,

The fact is that there are snowbows, the ice-crystal analogue to rainbows. They are a fairly rare phenomenon that forms when sunlight is reflected and refracted by ice crystals in the air (just as a normal rainbow is produced by the reflection and refraction of sunlight by raindrops). Snowbow colors are relatively faint because ice crystals are much poorer reflecting surfaces than raindrops. It’s possible to create a snowbow with a snow blower. On a cold day, when the sun is low in the sky, aim the discharge plume vertically. The low temperatures will allow the snow blower blades to chew the snow into tiny crystals, and a snowbow will appear opposite the sun.