A video has emerged from the United States of a massive waterspout which formed off the coast of Florida.

The impressive clip, which was filmed in Dunedin on August 18, shows the giant twister swirling close to the town.

"I spotted the waterspout from miles away because it was so huge and ominous," the filmer wrote online.

"When I arrived at the location it struck hardest, police were everywhere, trees down, firetrucks, building damage and a few unfortunate injured people including one child," the filmer added.

Waterspouts are very rare in Florida, especially one this large and powerful. It formed over Caladesi Island, over the Intercoastal of Pinellas county, Clearwater/Dunedin Florida on this day and headed directly for the Marina and downtown Dunedin. One man nearly lost his boat, which was anchored in the intercoastal as it almost struck him head on. The man reports that his boat was being flooded with water and on its side and nearly sank. Fortunately we have shallow waters in the area or he might have lost his boat and his life. Nobody in this area of Florida have ever seen a waterspout like this. Speculations say that it signals an especially severe hurricane season approaching and already here this year. My name is Kelly Ziolkowski and I was driving on this day in Dunedin, heading to the downtown area. I spotted the waterspout from miles away because it was so huge and ominous, and clearly pronounced with a perfect tornadic shape, starting high up in the clouds and with a massive fury of spinning water and some debris on the ocean surface. It looked truly terrifying even from 5+ miles away. I could see that it was indeed headed directly to downtown Dunedin and that meant a lot of trouble and big damage could occur. As an enthusiast storm chaser and photographer, I started driving towards it immediately and did my best to film it from my Samsung S8+ smartphone in the process. I have unique footage of the massive waterspout, filming it from the North, watching it hit downtown Dunedin just south of where I was at. When I arrived at the location it struck hardest, police were everywhere, trees down, firetrucks, building damage and a few unfortunate injured people including one child.