Rare ‘mother-of-pearl’ cloud spotted in Scotland

Sky-gazers across Scotland were treated to a rare sight on Sunday evening and Monday morning as Nacreous cloud was spotted.

As one of the highest clouds in our atmosphere, they form in very cold conditions and with their shimmering colours they are often referred to as “mother-of-pearl”.

One BBC Weather Watcher said “absolutely fantastic Nacreous cloud caught at tonight’s sunset with some gulls flying over. What a fantastic sight to behold”.

Nacreous cloud forms in very cold conditions over polar regions and within the stratosphere, around 12 to 19 miles high. Way above our normal clouds.

They are rarely spotted in the UK because of the very cold conditions needed.

Occasionally cold polar air, locked in place by strong winds high up in the atmosphere – called the polar vortex – weakens and allows this colder air to sink south to our latitude.

Nacreous clouds are mostly seen a couple of hours either side of sunset or sunrise and, being so high, they are still lit by sunlight which makes them appear even brighter in our evening sky.

Formed in air that is around minus 80 C, sunlight reflecting off tiny ice crystals in the cloud give it the pearly colours -the reason why they are also called mother-of-pearl.

On Sunday evening and Monday morning, BBC Weather Watchers from Moray, the Highlands and Aberdeenshire sent in their photographs.

Weather Watcher Helen said: “strange thing in the sky???”

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