Jonathan Yuhas Weather Wonders – Sun Dogs

Once a month, Jonathan will be visiting the Ruttger’s Blog and educating us on different weather wonders. This month, after Chris Ruttger shot this amazing picture of the Sun Dogs, we thought it was the perfect question for Jonathan…how do Sun Dogs occur?

Take it away, Jonathan!


Hey Everybody!

First of all when you see Sun Dogs, you know it is cold (the air temperature has to be less than 10 degrees).

Here is how and why Sun Dogs occur:

1. Tiny water droplets are always in the air even when temperatures are well below 32 degrees – these droplets are super-cooled water and are what cause clouds, fog, frost and snow when in high amounts.

2. When temperatures are cold below 10 degrees some of the tiny super cooled water droplets start to freeze into ice crystals – the colder it is, the more of the super cooled water droplets freeze and the more likely for Sun Dogs.

3. Color in the atmosphere is created by the way things bend light rays. In the Winter and right around sunrise for about 2 hours and within 2 hours of sunset the sun angle is at a low angle above the horizon. This causes the sun rays to bend more, forming more colors of orange, yellow and violet (the sun is yellow/orange at sunrise/sunset and white at noon).

4. For up to 24 hours after a snowfall with colder temperatures and bright sunshine the atmosphere is loaded with ice crystals. If the wind is blowing the light snow around it kicks up more ice crystals into the atmosphere so when the sun is first up and setting you can see what are called Sun Dogs. They are called Sun Dogs because the false appearing suns on both sides of the main sun look like a dogs tail.

So to sum it up:

They are caused by high amounts of tiny ice crystals that are usually in the form of tiny water droplets on warmer days, bending the light rays of the sun when it is at a low angle around sunrise and sunsets. Temperatures need to be below 10 degrees for Sun Dogs and the colder the more likely you are to see them.

Thank you, Jonathan! If you have a question that you would like to ask Jonathan and see answered here, you can email us at