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Does Wednesday's sun iris portend rain on Friday?

May 30 halo around the sun was caused by cirrus clouds, which often appear before a new weather front
Sun halo
This sun halo appeared to Bowen Islanders Wednesday afternoon.

If you had your eye on the sky Wednesday afternoon you may have seen what scientists call a 22° halo.

This ring around the sun (sometimes white, sometimes a rainbow) is caused by high cirrus clouds. For the ring to appear, the clouds must have little ice flecks of 20.5 micrometers or less. Light bounces through the ice, refracting, causing a ring like the one that graced the Bowen skies.

It’s called a 22-degree halo because the light is refracted at a 22 degree angle, so the ring appears to eyes that are at a 22 degree angle from the sun.

Because sun halos are formed in Cirrus clouds, which often arrive before a warm or cold front, they can be indicative of rain or other stormy weather. And indeed – rain is in the forecast for Friday!