The Alpine Lake fire 40 miles west of Riverton, Wyoming had been relatively quiet for the last ten days until it made some very significant runs on Friday and Saturday. On those days it showed extreme fire behavior, was plume-dominated, and spread six miles to the east adding about 11,000 acres, bringing the size to 34,630 acres. The Red Flag Warning that was in effect for the area turned out to be accurate, as the fire was influenced by extremely low relatively humidity. On Saturday the highest RH recorded at the Wind River weather station (12 miles southeast of the fire) for the 24-hour period was 17 percent at 11 p.m. Between 4 a.m. and 3 p.m. the RH was in the single digits, with the lowest reading of 6 percent occurring at 4 a.m. It remained quite low Saturday night and Sunday morning, finally getting as high as 25 percent at 7 a.m. on Sunday before it started decreasing again.
This weather contributed to the extreme fire behavior and rapid spread of the fire all day Saturday and continuing late into Saturday night.
We talked with Karl Brauneis, a former US Forest Service employee who is assigned as an Information Officer to the fire, which is burning on Bureau of Indian Affairs land.
Mr. Brauneis told us that since the fire started on August 7, the result of a lightning strike, it was managed by four to five people plus a helicopter and a helitack crew until they experimented with a Type 2 Incident Management Team for a short time beginning on September 7. He said the IMTeam was “too heavy” and “too muscled up” for the fire and was released. But after the fire activity increased later, they brought in a smaller Type 3 IMTeam, with Mike Hosstetler as Incident Commander.
Mr. Brauneis said the topography is extremely rugged, the area has no logging or grazing activity, and there is no wildland-urban interface. He described it as a “pre-Louis and Clark landscape”, meaning there is no development or any human-made improvements that have to be protected. Those factors, he explained, make it nearly impossible and not necessary to suppress the fire. When it burns down from the 8,000 to 10,000 foot elevations to the sage and grass on the lower slopes, which it is beginning to do now, they will be able to take suppression action. At that time the firefighters will engage the fire more aggressively, protecting the Saint Lawrence Basin and the Saint Lawrence Basin Ranger Station.
In fact on Saturday air tankers were used for the first time on the fire and included retardant drops from Tanker 911, a DC-10, as well as some single engine air tankers. They expect to use air tankers again on the fire today.
The video below was uploaded by KTWO News on September 7.