Firefighters face two blazes north of Durango

Colorado's Missionary Ridge fire flanked by Valley flames

Cyclists on Colorado Highway 550 pass the smoke of the Missionary Fire north of Durango.

DURANGO, Colorado (CNN) -- Firefighters hung their hopes on the weather Wednesday as two wildfires raged in national forest lands north of Durango, but conditions in the atmosphere have proved to be unreliable allies.

"It should be a little better than before," said fire information officer Richard Robinson. "We don't think the winds are going to be as strong today."

"But," he added, "there's the possibility of isolated storms later today, and with that comes gusty winds. That's the bigger problem -- gusty winds and lightning strikes."

There were unconfirmed reports that up to six homes were burned Tuesday by the sudden flare-up of the Valley fire, a mile west of the 67,000-acre Missionary Ridge blaze on the other side of the Animas River valley.

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Robinson said firefighters "thought this morning they had a line around" the Valley fire, but the command center had not received confirmation.

"They worked real hard on it ... I'm pretty sure they got the line around it, but the question is whether it holds," Robinson said.

Firefighters went after the 400-acre Valley fire -- dwarfed by the much larger Missionary Ridge blaze -- aggressively when it flared Tuesday, and hoped to contain it before it did more damage. Nearly 200 firefighters were dispatched to the scene.

More than 1,200 firefighters were battling the Missionary Ridge blaze, which has torched 71 structures -- 45 of them homes. More than 1,200 homes in ten subdivisions remain evacuated. Thirty percent of the larger fire has been contained, officials said.

Ninety residences were threatened by the Valley fire.

Officials said they were uncertain early Wednesday whether the Valley fire had been caused by a spark from Missionary Ridge, but said they believed it was likely a new burn.

Near Denver, where the Hayman fire scorched 137,000 as it threatened southern suburbs, firefighters had contained 77 percent of the blaze and allowed occupants of 350 residences to return to their homes.

The 9,000-acre Million fire, about 100 miles east of Durango in the Rio Grande National Forest, was said to be 55-percent contained Wednesday morning.