Smoke rolls over the Sabino Canyon area Wednesday as the Big Horn Fire grows to nearly 75,000 acres. An especially smoky day is expected over portions of Tucson and the community of Oracle.

 Bighorn Fire, Incident Command Team via Facebook

A hot day with more wind and low humidity will make fighting the Bighorn Fire a challenge, officials said Wednesday morning.

The wildfire started June 5 by lightning was estimated to be nearly 75,000 acres today and was 33% contained.

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Crews today will be working on trying to "stall" fire in the Sabino Canyon area, said Tim Reed, deputy incident commander for the Northern Rockies Incident Management Team. He said the fire continues to back down the mountain near the canyon. Crews igniting more fire lines in the Sabino Canyon area today could result in smokier skies over portions of Tucson.

"There's still a lot of work to be done," Reed said about firefighting efforts near Sabino, "but there's been good progress."

Burnouts are expected to be set today in the Oracle Ridge area. "The goal for today is to increase the fire-line on the edge to be able to handle any wind today," Reed said.

"We're feeling pretty good about where we're at," Reed said of firefighting efforts around the town. "If we have a good day today, the stage will be set for success."

Around Summerhaven, crews will continue to move the fire away from "values" and toward the Catalina Highway to connect with firefighting efforts there.

Reed said the eastern flank of the fire is moving toward remnants of the Burro Fire, the 2017 wildfire here that burned more than 21,000 acres.

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