Have you seen a wonderful aura around the moon recently? Here’s why.

Although great to look at, halos are actually more common than rainbows.

Lunar halos occur when there are high and thin clouds across the sky. Clouds are filled with countless ice crystals, each shaped like a tiny hexagon. Like a million small lighthouses, the crystals refract light through each other. The light is refracted by 22 degrees, which is the radius of the moon’s corona.

This phenomenon is visible both during the day and at night, and Gulf residents looking up on a Saturday night were lucky enough to experience it.

The fluffy clouds are expected to be replaced by storm ones later on Sunday. Little rain is expected in the Bay Area throughout the night, and it is cool enough that snow is possible at higher altitudes.

“Since temperatures are expected at / near freezing above 4,000 feet, some of the higher altitudes have the potential to see some slight snow accumulation!” The Bay Area National Weather Service tweeted Sunday morning. “Tonight, we’ll be watching Santa Lucia and the Diablo Ranges closely.”