"The fire continues to move through grass, brush, juniper and heavy timber stands," Hansen said.
Meanwhile, the threat had eased overnight to homes and businesses east of Hyrum, where the 2,200-acre Millville Fire was burning. No evacuations had been ordered, though Millville Canyon remained closed and Black Smith Fork Canyon was restricted to only through traffic as about 150 firefighters worked Monday to hem in the blaze.
Fire Information Officer Charity Parks said no structures had been lost and no injuries reported.
There was no estimate for when the Millville Fire might be contained, though Parks estimated crews had completed 10 percent of fire lines as of Monday night.
In Tooele County's Skull Valley, just east of the Goshute Indian Reservation, the 6,800-acre Patch Springs Fire continued to burn out of control. High winds that whipped the blaze through the weekend had eased by Monday, however, as some 75 firefighters scrambled to turn back the high desert inferno.
Several business, residential and storage structures had been threatened, but none had been lost as of Monday night.
Tinder-dry brush and juniper trees fueled the blaze, Fire Information Officer Joanna Wilson said.
"It stayed pretty active up until Sunday night, but overnight the temperatures went down and the humidity went up. This morning it looks pretty good," she said. "It did spread several hundred acres overnight, but we had no structural losses."
Crews also were keeping an eye on a the Mount Elmer Fire, which had burned about 10 acres in the Mount Naomi Wilderness Area near Logan. That operation was limited to monitoring the progress of the blaze, said Fire Information Officer Kathy Jo Pollock.