Winds threaten to fan Arizona flames
More than 900 firefighters battling Aspen fire
TUCSON, Arizona (CNN) -- High winds threatened to whip up a southern Arizona wildfire that had scorched more than 20,000 acres Tuesday as firefighters focused on a critical area where the flames threatened to sidestep firefighters' efforts to control them.
More than 900 firefighters were battling the Aspen fire around Mount Lemmon, north of Tucson, said Larry Humphrey, the incident commander for the interagency group fighting the blaze.
The greatest concern Tuesday afternoon was that high winds could push the fire around protective lines along the southeastern edge of the scorched area and into a Forest Service recreation area, Humphrey said.
The Aspen fire grew rapidly Monday and had scorched 20,850 acres as of midnight (3 a.m. Tuesday ET), he said. (Satellite image)
"We're expecting gusts this afternoon in the 40 mph range out of the southwest, so it's going to be another fun day for us," Humphrey said.
Firefighters have been able to limit the wildfire's spread by using aerial tankers and "burnouts," where they set fires to burn off fuel ahead of the advancing blaze. But Humphrey said high winds expected Tuesday could cause the blaze to "hook around" the fire lines.
"The way the winds are predicted, there's a fairly good chance we could lose it today down there," he said.
The Aspen fire was 15 percent contained Tuesday morning after growing rapidly Monday, said Rick Barton, a spokesman for the firefighters.
The week-old wildfire has destroyed more than 200 homes and businesses so far -- many of them in the vacation community of Summerhaven and nearby Loma Linda, which the flames swept through last week.
Smoke and flames from the mountaintop can be seen in nearby communities like Oracle, about 5 miles north of the Aspen fire, Humphrey said. But he said a patch of scorched terrain from a wildfire last year should keep the Aspen fire from threatening that town.
"We still feel confident we do not have to evacuate Oracle," Humphrey said.
More than 1,000 homes and a number of children's camps have been evacuated since the fire began June 17. Residents probably will not be able to return to their homes for at least a week, officials said.
The nearby Biosphere 2 research facility, which housed two teams of scientists in a sealed environment in the early 1990s, is within sight of the wildfire. But there is no immediate threat to the facility, which is now run by Columbia University, said Chuck Wood, the director of education there.
"We do have a good view out the window towards it," Wood said. "There's smoke and not nearly as much red flames as we saw yesterday. Yesterday was quite dramatic, with many trees bursting into flames and huge black palls of smoke above them."
Wood said Forest Service officials have told the university there is no need to evacuate, and some students have recently returned to the facility from trips around the state.
The cause of the wildfire is not known, since investigators are unable to approach the area where it is believed to have started.
Firefighters are facing their sixth straight day of extreme fire conditions, the longest stretch anyone involved in the firefighting effort can remember, Barton said.
Temperatures are expected to reach the upper 80s by Tuesday afternoon, with single-digit humidity. Forecasters predict sustained winds of 20 mph and gusts up to 40 mph, Barton said.
A total of 913 people, backed by 11 helicopters and 25 fire engines, are involved in battling the fire, he said.
Firefighters have been hindered by the steep terrain on the slopes of the 9,157-foot Mount Lemmon, which prevents them from using some heavy equipment. But the Aspen fire has run up against fire lines left behind from two wildfires last year, and roads built to battle those blazes are being used to move firefighters and heavy equipment, Barton said.