These images show a rare 'flat tornado' that was spotted spanning nearly an entire coastline.

Picture shows the meteorological formation known as Morning Gloria in the sky over Sochi, Russia, undated. Note: Private photo taken from social media. (Newsflash/NX)

The unusual sight was spotted in the Russian resort city of Sochi, on 6th April.

The breathtaking images that show a horizontally elongated cloud, resembling a huge roll, attracted widespread attention and reportedly became a subject of discussion among atmospheric scientists.

These impressive cloud structures are of colossal size and are usually found in Australia.

They can stretch for 1,000 kilometres (621 miles) in length, reach a height of two kilometres (1.24 miles), and move with incredible speeds of up to 60 kph (37 mph).