MOFFAT COUNTY, Colo. (CBS4) – The Divide Fire has now burned nearly 20,000 acres in Moffat County.

The fire started on June 29 more than 20 miles north of Craig. It’s about 40 percent contained.

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Divide Fire on July 4. (credit: InciWeb)

More than 70 fire personnel are there fighting the fire.

Strong wind speeds have fueled the flames. Firefighters from Thornton Fire Department at the Divide Fire shared a picture of a fire whirl on Saturday.

Fire whirl at the Divide Fire. (credit: Thornton Fire Dept.)

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Meteorologist Chris Spears explains the phenomenon.

LINK: Divide Fire InciWeb Page

Wildfire Resources

– Visit’s Colorado Wildfire section.

Wildfire Photo Galleries

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– See images from the most destructive wildfires (Black Forest, Waldo Canyon, High Park and Fourmile), the deadliest (Storm King) and largest wildfire (Hayman) in Colorado history.