A long, thin waterspout formed off the coast of Indonesia, shocking beachside residents who spotted the terrifying weather phenomenon.

The vorted was filmed twisting just past a neighbourhood in Tanjunpinang City in Riau Islands province on September 8.

Nakadha Riski, a resident, said: 'The vortex suddenly appeared and immediately grew in size. It looked like it was absorbing water and carrying it into the clouds.'

He added that strong winds were felt a few kilometres from the shore, but did not cause any damage.

Nakadha said: 'It moved far from the settlements and away from the mainland.'

Waterspout tornadoes form when wind merges from opposite directions near the water's surface, creating a small area of spin. Warm air at the surface causes the spinning air to rotate faster and it starts to rise – picking up water at the same time and forming the distinctive elephant-funnel shape.

As warm air rises, the cooler air moves in below and then rises, too. Sometimes the air spins so fast that it stretches and a funnel appears from the water to the thunderstorm cloud above.