Even though the Hewlett Fire in the Poudre Canyon grew to right around 640 acres yesterday, there was good news as the fire moved away from homes. Some unfortunate news also came out Tuesday though. Undersheriff Bill Nelson said it appeared the fire was man-caused. 

“There's no obvious natural cause for the fire." Nelson told the Larimer County commissioners on Tuesday. “I think it's probably accidental.”

Until the cause of the fire is confirmed, he did not release any additional details, and the U.S. Forest Service also hasn't released any information on the potential cause of the fire, which started about 1 p.m. Monday.

The now 640 acre fire is near the Hewlett Gulch Trail about 10 miles up Colorado 14 from Ted's Place. A thick layer of black smoke is visible from Fort Collins, and the Hewlett Gulch and Greyrock Trails remain closed.