The Little Devil Fire more than doubled Thursday, consuming an estimated 70 acres of the within the San Juan National Forest.

The National Forest Service for that district said Thursday afternoon that a heavy air tanker had been grounded because of wind, but single-engine air tankers and a helicopter have been working the fire.

Lightning -parked the blaze in a rugged area three miles north of the intersection of U.S. Highway 160 and Colorado Highway 150, said Ann Bond, a Forest Service spokeswoman.

A heavy air tanker arrived Thursday, joining a fleet made up of two state of Colorado single-engine air tankers and a helicopter in the fight, she said.

Two 20-person crews, a local Pagosa District crew and eight smokejumpers, are fighting the fire on the ground. Another 20-person crew is en route, and a hot-shot crew was expected to arrive Thursday evening, she said.

Bond said no structures are in danger, but crews are actively working to protect a power line.

The Forest Service was forced to close two roads Thursday as the fire spread in a remote area between Bayfield and Pagosa Springs.

Forest Road No. 627, known as Devil Mountain Road, and Forest Road No. 626, which accesses the Devil Creek State Wildlife Area, are shut off until further notice.

The fire was first reported Tuesday, but it likely smoldered on the forest floor for a while.

The weather forecast calls for hot, dry conditions to continue, at least until the weekend.

jromeo@durangoherald.com

Correction: An earlier version of this story incorrectly said the the Little Devil Fire is burning in the Devil Creek State Wildlife Area. It is burning in the San Juan National Forest.