New Video: 'Firenado' Forms In Beaver Creek Fire

WALDEN, Colo. (CBS4) - The Beaver Creek Fire has burned more than 36,000 acres since it started nearly two months ago. A firefighter captured a rare occurrence inside the fire lines-- a firenado.

Firenados or fire whirls happen when rising heat and turbulent winds combine to create a twister.

Crews have the Beaver Creek Fire burning near the Colorado-Wyoming border more than 40 percent contained. It has destroyed a cabin and several outbuildings.

The fire continues to grow, but slowly. Low humidity has helped fuel the fire but calm winds have helped fire crews in recent days.

What started the fire in June has not been determined. Officials believe the fire will be fully contained by October.

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