Weather: Incredible 'ice halo' over Mt Cook Aero

The ice halo.
The ice halo. Photo credit: MetService / Twitter

An incredible photo has captured a stunning 'ice halo' over Mt Cook Aero.

When there are wispy high clouds in the sky made of ice, the sunlight passes through them and gets bent in another direction, which can create these incredible images.

"22-degree halos are created by refraction of light through randomly oriented hexagonal prism-shaped ice crystals," MetService explains.

"Light is refracted as it enters through one face of the hexagonal ice crystal, and is refracted once more as it exits through another face.

"Due to the geometry of the ice crystal, rays of light are deflected through angles between 22-degrees and 50-degrees but more rays are deflected at angles of around 22-degrees.

"This concentrates the light at this angle, creating a circle that is brighter than the sky around it."

It's the latest in what has been a series of stunning images in the area. On Friday, photographer Susan Blick snapped what looks like tui crossing over Mt Cook.

"Does it get anymore kiwi than this? A tui borne of Aoraki! Yep, that's Mt Cook it's perched on," she posted to Facebook.

"Tonight's high winds had the clouds dancing, but to form a deadset tui is something else.  And no I didn't have to 'tidy it up' at all, that's exactly as the cloud was bizarre."