See 'firenado' rip through major California wildfire

Saturday, June 18, 2016, 7:26 PM - As the Sherpa wildfire in Santa Barbara County, California continues to grow, incredible video of a fast-moving "firenado" was caught on camera in Refugio Canyon Thursday evening.

Also known as a "fire whirl," they form as the result of hot, dry air rising quickly from the ground. Footage of the firenado can be seen below.

"Although the source of energy for a fire whirl is very different than for a tornado - the tornado gets it from storm cloud above, while the fire whirl's energy comes from the fire below - they form in roughly the same way," says The Weather Network meteorologist Scott Sutherland.

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"The atmosphere naturally sets up rolling 'tubes' of air above the ground, as friction slows down the winds closest to the ground, which then introduces a drag on the winds above, pulling them down slightly, and this cascades upward. When these kinds of tubes encounter a powerful updraft, like the ones flowing into the bottom of a thunderstorm or the ones created by the heated air from a roaring fire, the tube turns from horizontal to vertical and the updraft causes it to rotate faster and tighten up into these powerful spinning vortexes."

According to Sutherland, fire whirls can be smaller in nature but they can also strengthen to an EF2 or EF3 tornado.

They tend to last for only a few moments, which is why they are rarely caught on camera.

The brush fire in Santa Barbara County more than tripled in size Friday due to strong winds, rising temperatures and an extended drought. It has covered over 7,500 acres and is 45 per cent contained, according to Cal Fire captain Richard Cordova. Over 2,000 firefighters are currently battling the blaze.

The county declared a state of emergency as the blaze spread over the Santa Ynez Mountains. Mandatory evacuation orders are in place for El Capitan, Refugio, Venadito and Las Flores canyons north of Santa Barbara.

The cause of the wildfire is under investigation.

SOURCE: Yahoo News

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