The water was not the only thing making waves off the Norfolk coast as a rare cloud phenomenon was captured by a lucky local.

A Kelvin-Helmholtz cloud was seen in the sky over the sea at Trimingham on Sunday evening.

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According to the Met Office, Kelvin-Helmholtz is one of the rarest cloud types, occurring when two different layers of air are moving at different speeds.

This causes winds to blow faster at the upper level than at the lower levels.

North Norfolk News: A Kelvin-Helmholtz cloud was seen in the sky over the sea at TriminghamA Kelvin-Helmholtz cloud was seen in the sky over the sea at Trimingham (Image: Joy Patrick)

The result is the appearance of a repeating breaking wave pattern, formed similarly to waves over the sea, which are created when the wind blows faster than the water moves.

Joy Patrick was lucky enough to capture the event from her window.

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"It really was fleeting," she said. "I was walking into my bedroom to close the windows and curtains and saw the cloud.

"I took the photo, went into the bedroom and when I came out it had totally disappeared.

"It was magical, I feel very privileged to have witnessed it."