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© Gary Robbins
If you looked at the sky this afternoon about 4 p.m. you might have noticed a beautiful phenomenon that's common but doesn't seem that way because it last so briefly. Its official name is iridescence, although I refer to the phenomenon as "mini rainbows" because large portions of the edges of clouds briefly exhibit many of the colors of the rainbow, in a more muted tone. Today's clouds were shaded pink and blue and teal.

You can "compare this (phenomenon) to a prism," says Stefanie Sullivan, a forecaster at the National Weather Service. "Sunlight passes through the clouds at different wave lengths, bending the light at different angles so you can see the whole spectrum of colors instead of just white."

Today's iridescene appeared in cirrus clouds that were moving east at about 35 mph at an altitiude of 20,000 to 25,000 feet. "This happens fairly frequently," Sullivan says. "But you don't always see if because the sun has to be at just the right angle and the cirrus has to have the right ice crystals."

It was plenty cold up where the cirrus was moving today - minus 15 degrees to minus 20 degrees, says Sullivan. On the ground, however, temperatures warmed to the 60s and low 70s, and will get even hotter tomorrow as dry, weak offshore winds blow haze out to sea, as they did today. Just before sunset, you also could have seen a thin line of white clouds that looked like they were half way up the western side of Santa Catalina Island. You would have been looking at haze and the inversion area, or a region where warmer air was sitting atop cooler air.