This is an archived article that was published on sltrib.com in 2016, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

Crews on Wednesday were steadily closing containment lines around a week-old wildfire that had blackened 1,313 acres along the Utah-Wyoming border.

Fire Incident Commander Shane Greer said the Tokewanna Fire was 58 percent contained, though he cautioned that a continuing cycle of thunderstorms — accompanied by dry lightning — had an army of 500 firefighters concerned.

"Increased fire activity is possible ahead of a cold front that is forecast to pass over the fire," he stated. "Ahead of the front, warm temperatures, relative humidity values of 12 percent, and winds gusting to 25 mph will test containment."

While a Red Flag Warning for potentially explosive wildfire conditions was in place Wednesday for the region, residents of the 140 homes in the Tokewanna Estates subdivision, Blacks Fork River Estates, and surrounding areas were allowed to return. They had been evacuated on July 28 as flames destroyed eight homes.

Greer said the perimeter of the blaze, burning in timber and brush, stretched nearly 16 miles through the steep, rugged and forested terrain, some 15 miles south of Mountain View, Wyo.

Early on, flames had come within a mile of the Utah state line.

Wednesday's work focused on improving and expanding fire breaks on the ground, while air tankers and helicopters struck from above with tons of fire retardant and water.

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