FLAGSTAFF, Ariz. — Firefighters took advantage of cooler, calmer weather Friday to get an upper hand on a blaze burning in a scenic Arizona canyon as Memorial Day travelers were forced to alter travel plans because of the fire.
Hotshot crews marched along a winding highway that is a key front in their effort and set fire to the ground to rob the wildfire of fuel and keep it from crossing the road. Helicopters dropped explosive chemicals in the steepest parts of the canyon that firefighters can’t reach. Crews were also busy widening a line that would keep the fire from burning toward residential areas.
‘‘There might be a huge spike in size, but we want the public to know we’re controlling the fire,’’ fire spokesman Dillon Winiecki said. ‘‘We are fighting it on our own terms.’’
The human-caused Slide Fire started Tuesday and by Friday had burned more than 11.5 square miles in and around Oak Creek Canyon, a scenic recreation zone along the highway between Sedona and Flagstaff that normally would be filled with tourists as Memorial Day approaches.
Slide Rock State Park is among the destinations that are closed. It is one of the most-visited tourist spots in Arizona, with swimming holes and natural water slides that draw tens of thousands of people during summer months.
Weather conditions for the fire over the next several days look favorable, with increased humidity and a chance of rain. Firefighters established containment lines around 5 percent of the fire nearest to where it started just north of Slide Rock State Park.
Crews were making good progress in keeping the blaze from getting closer to communities south of Flagstaff, incident commander Tony Sciacca said. Their work includes putting a sprinkler system around a fish hatchery in the canyon that can be turned on if the fire approaches, creating a buffer zone near a power line, and quickly knocking down any spot fires that escape the main blaze.
Some 900 firefighters were assigned to the fire Friday.
The fire was moving away from Sedona, but that didn’t ease concerns of business owners who worry the blaze will keep customers away from the premier tourist destination over the weekend.
The Sedona Chamber of Commerce has been fielding hundreds of inquiries via telephone and social media from people wondering if they should still visit during the holiday weekend and inquiring about the air quality, officials said.
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 along more than 200 miles of trails.
Evacuations remain in place for a 2-mile stretch north of Slide Rock, and Highway 89A between Flagstaff and Sedona is closed. The fire was 3 to 3½ miles away from the residential areas of Forest Highlands and Kachina Village.