Of all the colors that the weather can produce in the sky, rainbows are probably the most familiar, but they're not that common around here in winter. There are other colorful displays to look for, two of which are halos and sun dogs. These form when sunlight passes through a thin layer of ice clouds. The ice crystals act like tiny prisms, breaking the sunlight up into colors.

As the name implies, a halo is a complete ring around the sun. To create a halo, sunlight has to pass through a fairly uniform and extensive layer of ice clouds. To capture a halo on film, it's sometimes necessary to block out the sun using a building or a person, as seen in these photos.

If the clouds are more patchy, you may not get a full ring, but rather just a splotch of colored light on one or both sides of the sun. These are called sun dogs. Their name is based on their position, not their shape - you'll always find them in line with the sun, appearing to heel at the side of their master.

To get a sense for how far sun dogs and halos appear from the sun, cover the sun with your thumb, and stretch out your hand. The tip of your little finger will fall at roughly the right distance from the sun.