A waterspout described as the “biggest of a lifetime” has been spotted off the coast of south Wales as strong winds hit the UK.

James Thomas, 47, an agent in the watersports industry, spotted the unusual phenomenon at Llantwit Major Beach in south Wales on Saturday morning.

“As I stood there watching, I thought to myself, this is probably the best example of a waterspout that I will ever get to see in my lifetime,” Mr Thomas told the PA news agency.

“Over the years I have seen quite a few of these over the Bristol Channel, but this was by far the biggest.”

Also known as funnel clouds or tuba, waterspouts form when a rotating column of wind draws in cloud droplets, according to the Met Office.

Mr Thomas said he spied Saturday’s weather spectacle while watching a surfing contest.

“It started off fairly small, and quite high in the sky, and as we continued to watch, it appeared to get darker and began angling itself towards the surface of the sea, as if it was coming towards us,” he said.

“I quickly realised it was a waterspout when I could see the rotating spray on the water’s surface, like a magnetic energy.

“I was shouting to all the competitors to look up and see this phenomenal natural occurrence.”

The sighting comes as the Met Office warned parts of the UK may have seen tornadoes on Sunday, as strong winds and rain batter the country.

Gusts of over 80mph have been recorded and yellow warnings for wind and rain are in place over large parts of the west and elsewhere.