The fire began around noon Saturday north of Jamestown, according to Gabi Boerkircher, spokesperson for Boulder Officer of Emergency Management.
Jamestown is in the foothills of the Rocky Mountains, about 14 miles northwest of Boulder and about 43 miles northwest of Denver.
The fire is being pushed southeast by winds, Boerkircher said.
“We’re asking people pretty much anywhere in that vicinity to be sure they’re making an evacuation plan,” Boerkircher said, adding that a local disaster declaration was signed around 1:30 p.m. local time in response to the fire.
Evacuations have been ordered for Jamestown and pre-evacuation orders are in place for areas south of the town, Boerkircher said.
No deaths or injuries have been reported and a cause of the Calwood Fire has not yet been determined, Boerkircher said.