A half-dozen forest and brush fires sparked by lightning raged through west-central Utah after tripling in size overnight. Authorities estimated that the fires had burned across 28,000 acres. "That fire . . . made a five-mile run in five minutes," said Linda Jackson, fire information officer for the Fish Lake National Forest in Cove Fort, Utah. Temperatures were only in the upper 80s but officials said high temperatures and dry conditions had fueled the blaze. The fires ignited late Thursday and were scattered over a 375-square-mile region of state and federal land about 150 miles southwest of Salt Lake City. About 1,000 firefighters fought the blaze, assisted by 10 fire engines, five helicopters, two air tankers and seven bulldozers.