The Bighorn Fire in the Catalina Mountains has grown to 37,000 acres and has been burning for more than two weeks.

 Kelly Presnell / Arizona Daily Star

Crews were planning Friday night to conduct controlled burns south of Oracle in their efforts to stop the northward advance of the Bighorn Fire.

Favorable weather conditions were allowing crews to start the burns directly south of the community of Oracle and work in both east and west directions, said Rocky Gilbert, a fire operations chief for the team fighting the wildfire. The work was expected to last well into the night.

Gilbert said residents in the Oracle area would likely see an increase in smoke and fire, but it will be from controlled burns not the actual Bighorn blaze. The effort is part of a defensive strategy to help protect Oracle and the town of San Manuel from the fire, which has doubled in size this week and is still threatening several communities.

On Mount Lemmon in the Catalina Mountains, crews have managed to build containment lines and conduct burnouts around the northern and southern edges of Summerhaven that should help protect the village from any advancing fire, Gilbert said.

This video was taken on June 17 with the camera pointed to the northwest near the Mount Lemmon Fire District. Video courtesy of Southern Arizona Timelapses.

Some controlled burning was being done Friday in the Bear Wallow area to protect homes there, he said.

The fire, which started with a lightning strike June 5, has burned 37,000 acres and is 40% contained. There are about 900 people working the blaze.

On the southern edge, fire activity picked up in Ventana and Esperero canyons, creating a large amount of smoke Friday afternoon that was visible from Tucson. The sharp increase in fire behavior was expected, Gilbert said.

Crews will likely be sent into those areas Saturday to begin defensive measures against the fire and to protect the communities in the Foothills, he said.

Evacuations remain in place for Mount Lemmon, from Summerhaven down to Willow Canyon. There are also evacuations in place around the Peppersauce Canyon area in Pinal County. The community of Oracle remains in the “set” status under the state’s “Ready, Set, Go” evacuation system.

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