Weather Blog

'Fire rainbows' out to mark summer's inauguration

'Fire rainbows' out to mark summer's inauguration
Photo of fire rainbow taken by Janis Orland of Ashford, Wash. on June 20, 2012.

Summer's coronation around Western Washington was marked with several special guests -- most notably a glistening Mt. Rainier and quite a few sightings of "fire rainbows" and sun halos.

The rainbows are caused by ice crystals in the thin, distant clouds being at just the correct angle to refract the sunlight into the colors of the prism.

These fire rainbows are rare sights in the mid-latitudes, because they can only occur when the sun is 58 degrees or higher above the horizon. For the Northwest, that pretty much relegates any sightings to roughly around 6 weeks either side of the summer solstice. So sure enough we are in prime "fire rainbow" season for the next several weeks.

The sun halos work the same way -- getting the clouds just at the right angle to the sun to refract sunlight into a prism.

So any time you see those wispy clouds around, keep your eyes peeled!

(And welcome, summer!)