KACHINA VILLAGE, Ariz. — Hundreds of firefighters are working to protect communities from a wildfire chewing up a scenic Arizona canyon, but some business owners worry that the blaze will keep customers away from the premier tourist area over the important holiday weekend.
The human-caused Slide Fire started Tuesday and by Thursday night had burned more than 11 1/2 square miles in and around Oak Creek Canyon, a scenic recreation zone along a highway between Sedona and Flagstaff that normally would be teeming with tourists as Memorial Day approaches.
Firefighters established containment lines around 5 percent of the fire by late Thursday and were making good progress in keeping the fire from getting closer to communities south of Flagstaff, incident commander Tony Sciacca said Friday.
"Everything is holding this morning," Sciacca told reporters during a briefing.
Weather conditions for the next several days look favorable, with increased humidity and a chance of rain, though rain also could lead to rock falls off steep canyon slopes denuded of vegetation, he said.
The Sedona Chamber of Commerce has been fielding hundreds of inquiries via telephone and social media from visitors wondering if they should still visit during the holiday weekend and about the air quality, officials said.
Many Sedona business owners also have taken to social media to remind people the resort town is open for business, but it hasn't kept some from changing their plans.
Pink Jeep Tours, which offers tours of Sedona's famous red-rock landscape, has already had some cancellations and is seeing fewer bookings for a holiday weekend.
Chamber of Commerce President Jennifer Wesselhoff said smoke from the fire has been visible from about 3 a.m. to 9 a.m., but the skies clear up as soon as the sun emerges. She said visitors can still go hiking in most areas after 9 a.m. and not see any smoke.
The fire grew tenfold from Wednesday and from 7 1/2 square miles earlier Thursday. There have been no reports so far of injuries or structures burned.
The fire still was 3 to 3 1/2 miles away from the residential areas of Forest Highlands and Katina Village, where 3,200 residents remained under pre-evacuation warnings.
Officials were mindful of the fire's dangers, as they looked at giant flames shooting up the walls of the canyon and saw how hot the fire was burning in the tinder-dry drought conditions.
"The fuels are just so dry, entire trees are turning to ash," said Dick Fleishman, a spokesman for fire managers.
A primary focus of firefighting efforts will be to pinch off the fire where it has reached the top of the canyon's northeast corner to keep it from burning north toward residential areas, he said.
Sciacca said 900 firefighters were assigned to the fire Friday, including 35 hand and at least 35 engine crews.
Firefighters are also taking extra steps to make sure they don't lose communication with crews in the steep canyons. They brought in "repeaters" that look like 20-foot-tall antennas and placed them on overlooks to maintain radio contact with firefighters below. Radio communication issues were a problem last year in a fire in nearby Prescott that killed 19 firefighters who were part of a Hotshot crew.
"If the fire makes any unfavorable movement, we know about it and I can alert them," said firefighter Rich Sack of the Carson Hotshots in Taos, New Mexico, as he held a radio and intently kept an eye on the fire.
Fleishman said thunderstorms could bring much-needed rain and moisture to dampen the blaze, but also lightning strikes that could start additional fires and powerful downdrafts that could push the blaze erratically in all directions.
"That's what happened with the Prescott guys last year," he said.
As smoke billowed over their homes, many residents of Kachina Village and Forest Highlands got out of town Wednesday rather than wait for an evacuation order.
The fire has closed the main road between Sedona and Flagstaff forced the evacuations of 100 threatened businesses and homes in a 2-mile stretch north of Slide Rock State Park, a popular recreation area because of its natural rock water slides.
In southern Arizona, a wildfire on the Tohono O'odham Indian Reservation was fully contained Thursday after charring more than 200 acres. The fire southwest of Tucson was reported Tuesday night. Officials say no structures were damaged and no residents were evacuated.
Associated Press writers Paul Davenport, Walter Berry and Terry Tang in Phoenix contributed to this report.