Fire crews continued to work mostly within the perimeter of the Little Sand Fire near Pagosa Springs on Monday and built firelines along U.S. Forest Service Road 639.
The problems were manageable considering what firefighters are dealing with in southwestern New Mexico.
The goal is to keep the fire where it is north of the Piedra River near Pagosa Springs.
The lightning-sparked fire has burned 3,133 acres since May 13. No structures have been destroyed.
Some additional acres burned Tuesday because the fire was moving toward the Piedra River, carried by timber litter, a news release said.
But its not all outward growth, said Laura McConnell, the public information officer for the Rocky Mountain Type 2 Incident Management Team. In some places, the fire ran back up the hill into fuel.
At the south end of the fire, crews will establish an anchor to try to keep the fire from crossing the river.
Smoke in the air is likely to be seen in the Piedra Valley.
In western Colorado, firefighters made significant progress in extending and strengthening a line around the Sunrise Mine Fire near Paradox. The majority of the work was done on the southwest side of the fire.
Firefighters were aided by helicopter water drops.
The fire is burning on public land about four miles north of Paradox, some 100 miles northwest of Durango, near the Colorado-Utah border.
Lighter winds Tuesday allowed crews to improve fire lines, leading to 48 percent containment as of 8 p.m., according to Public Information Officer David Eaker.
The cause of the fire, which has burned more than 6,000 acres, is under investigation.
In New Mexico, two lightning-sparked blazes that merged in a mountainous forest in the states southwest are close to becoming the largest wildfire in state history, fire officials said Tuesday.
The Forest Service said the erratic blaze in Gila National Forest had grown to about 152,000 acres by Tuesday just 5,000 acres from breaking the state record. It is about 15 miles east of Glenwood, N.M., a small town with a few hundred residents.
More than 1,100 firefighters and nine helicopters from around the state were fighting the blaze. But officials said extremely low humidity will keep making efforts against the fire difficult.
The two lightning-sparked fires merged last week to form the giant blaze, which has destroyed 12 cabins and seven small outbuildings.
One fire was first spotted May 9, and the second blaze was sparked May 16, but nearly all of the growth has come in recent days fueled by relentless winds.
Officials also said a record-breaking dry air mass and persistent drought in the region contributed to the fires growth.
Those winds forced crews to the sidelines last week as the fire rapidly spread in an isolated area and charred several homes in the community of Willow Creek, which remains under evacuation. Smoke has spread across New Mexico and parts of Arizona, putting cities as far away as Albuquerque under health alerts.
Officials said areas around some of New Mexicos largest cities, including Albuquerque and as far southeast as Roswell, will see smoke by late Tuesday.
U.S. Sen. Jeff Bingaman said Tuesday the Federal Emergency Management Agency has approved New Mexicos request for fire-management assistance declaration for the Whitewater-Baldy Fire Complex burning in Catron and Grant counties.
firstname.lastname@example.org The Associated Press contributed to this report.