The Wapiti Fire near Stanley creates its own weather during the heat of the afternoon(U.S. Forest Service}
The worst may be over for the Wapiti fire burning west and north of Stanley.
The huge clouds rising out of the Wapiti Fire the last week of August displayed the fierce behavior of the fire with which westerners have become accustomed. For Stanley Mayor Steve Botti, a retired National Park Service fire ecologist, it was “surrealistic.”
“It’s hard to describe what we saw last week,” said Botti. “The immensity of the pyro cumulus cloud was amazing.”
Pyro cumulus clouds, caused by the rising heat of wind-blown fires in thick dry fuel, form when a hot fire causes an updraft, carrying the warm dry air up to a layer of air with water vapor it pushes higher to form a cumulus cloud. If fire heated cloud rises high enough it become a pyrocumulonimbus, which can generate thunderstorms, rain and even lightning.
In extreme cases, like in the Park Fire this year is California, the storm can generate a fire tornado.
I have seen where a fire was hot enough to create its own weather and then later watch the convection cloud collapse on itself. It’s a case of basic thermodynamics. Hot air rises, you get updrafts. When the fire no longer produces enough heat you get downdrafts.
Botti has been involved in wildland fire for 51 years. Since he retired, he has been active in the Sawtooth fire collaborative, which has sought to make the fires in the valley less fierce and the homes safer.
“We had a real crisis period for two or three days with possible evacuation of the town,” Botti said.
Firefighters controlled burnouts around subdivisions west of Stanley, which protected them to a degree. When a spot fire from one of the burnouts burn from the north near lower Stanley, the residents were evacuated. Botti called retired Idaho Department of Fish and Game warden Gary Gadwa, who was inside the Frank Church River of No Return Wilderness up on the Pinyon Peak Fire lookout, 20 miles north of his home in lower Stanley. The fire he said was two hours away from burning into his yard.
“He must have felt helpless,” Botti said.
But firefighters got onto the blaze with all the people and equipment they could muster and saved the town. Botti is hopeful that the emergency is over.
Fire seasons have gotten longer and fire behavior has become fierce across the world as global warming has made the American West, Eastern Russia, Australia and other areas hotter and drier over the last 30 years. Older firefighters saw few pyro cumulus clouds prior to 1988 when the huge fires in Yellowstone created frequent columns of smoke and water vapor that reporters compared to atomic bomb mushroom clouds.
I just wrote about the Big Blowup in 1910 when 3 million acres burned in a few days. When I started covering fires in the 1980s, the old timers talked about the Sundance Fire that created a huge pyro cumulus cloud Sept. 1, 1967. It burned 55,000 acres of forestland near Priest Lake that day, setting the upper bar for a generation of firefighters until Yellowstone.
Now such fires are an annual event. The season lasts longer, and smoke fills up areas throughout the West for much of the summer. The Wapiti fire is going to burn into the fall.
“Pray for rain or snow that’s the only thing that’s going to stop this,” Botti said.
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