A waterspout tornado stretched up into the sky over a Thai beach.

Footage shows dark, thick clouds covering the sky as the water vortex whirls in the ocean at Mu Ko Similan National Park in Phang Nga, Thailand, on November 9.

Two types of tornado form at sea - tornadic waterspouts and fair-weather waterspouts. Tornadic waterspouts form from thunderstorms, just like land tornadoes, while fair-weather waterspouts are typically smaller and less powerful without the need for storms.

Both types of waterspout tornadoes are created when there is a strong difference in air pressure between the surface of the water and the air above it. This difference in pressure creates an updraft, which draws air from the surface of the water into the atmosphere. As the air rises, it cools and condenses, forming a cloud. The cloud can then rotate, forming a waterspout.

It is rare for waterspouts to cause severe damage. However, in August 2023 two tourists were killed and six injured when a waterspout tornado hit their boat on an estuary river in Phetchaburi, southern Thailand.