Powerful smoke gustnado forms during California bushfire

A large bushfire has triggered a spectacular smoke "gustnado" in north-western Los Angeles.

Video shared by Fox LA showed the plumes of smoke from a spot fire swirling in an upwards direction, and into a large vortex shape on Friday afternoon (local time).

It then appeared to dissipate slightly, as a firefighting helicopter drops water on the blaze causing the gustnado.

The dramatic weather event is not considered to be a tornado, but a “short-lived, ground-based swirling wind”, according to AccuWeather.

In the time since the gustnado was captured on camera, the small fire that triggered it has grown into a 25-acre bushfire in the Gorman region, a Los Angeles County Fire Department spokesman told Fox LA.

The fire is not threatening properties, the spokesman added.