This is an archived article that was published on in 2016, and information in the article may be outdated.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

Cooler temperatures were helping crews made progress Monday against two active wildfires in Utah, though thunderstorms proved a mixed blessing.

Box Elder County Fire Information Officer Joan Hammer said the Broad Mouth Fire was 42 percent contained and had burned 20,614 acres. About 205 firefighters and a fleet of fire retardant- and water-bearing air tankers and helicopters were helping hem in the blaze near the Utah-Idaho border town of Plymouth.

No additional structures had been lost since the fire's initial consumption last week of a cabin, camping trailer and a shed. The fire had, early on, threatened a couple area ranches and the Spirit Ridge Rifle Golf Club, but has since been spreading slowly north toward the Pocatello Valley, through remote grass, rangeland and timber.

The Box Canyon Fire, about 20 miles east of the Summit County town of Oakley, had burned 2,468 acres of conifer, aspen and grass on steep, rocky terrain. No containment was in sight.

Gusty winds from generally dry thunderstorms over the weekend was blamed for about 100 acres' growth, but most of that was within the perimeter of the blaze where dead logs and the dry forest floor continued to smolder.

About 90 firefighters, aided by water-bearing helicopter flights, worked to shore up natural fire breaks and digging new lines ahead of anticipated fire growth routes.

Ledgefork Campground and the boat launch at Smith and Morehouse remained closed to the public.

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