- The Forsyth Fire was sparked by lightning 10 days before the fire was reported.
- Last week's strong winds spread the fire that was smoldering in a tree, destroying 18 structures and prompting evacuations.
- Firefighters face challenges with hot and dry conditions returning this week.
PINE VALLEY, Washington County — Firefighters say they have found the origin of the Forsyth Fire — they believe lightning hit a tree more than a week before the fire began racing toward the Pine Valley community.
Dixie National Forest officials shared photos of a scorched, hollowed-out tree within the forest Tuesday evening, where the fire's starting point was. An incident commander from the initial attack team spotted the tree the same day reports of a wildfire near Pine Valley came in last week, quickly leading to an evacuation of the area.
Investigators reviewed weather data and found that a thunderstorm had moved through the Forsyth Canyon area 10 days before the fire was reported, and that lightning had struck in the steep, remote section of the forest. This is likely when the tree caught on fire, but it wasn't noticeable at first.
Investigators found that the tree's base was struck, igniting an internal fire within its trunk. The heat began to vaporize the tree's sap and moisture.
"This intense heat ignites the wood from within, creating a slow, flameless form of combustion known as smoldering. This can continue within the tree for an extended period, even days or weeks, without an obvious flame," the agency wrote.
Last week's strong wind gusts likely carried the fire from inside the tree to the forest around it, which is when smoke became visible for the first time, and the fire was reported. By then, the mix of wind, heat and low relative humidity made it easy for flames to race down the canyon toward Pine Valley, where it destroyed 18 structures, including 14 primary or secondary homes.
Hundreds of residents remain under evacuation.
The fire has now burned about 8,900 acres and remains 0% contained, according to a Great Basin Complex Incident Management Team 7 update Wednesday. Mike Johnston, the team's incident commander, said some crews have been working within Pine Valley to make sure that buildings are protected in case the fire shifts back toward the community.
Hot and dry conditions are forecast for the remainder of the week, posing unfavorable conditions for firefighters. Close to 700 personnel are now assigned to battle the fire.
France Canyon Fire 15% contained
More than 750 firefighting personnel remain assigned to the France Canyon Fire, which is burning closer to Bryce Canyon in southern Utah. The state's largest fire of the season has burned over 27,000 acres since lightning sparked it on June 11.
Crews gained a little more control on Tuesday, increasing containment to 15%.
Garkane Energy cut some power supply on Wednesday morning so crews can conduct a controlled burn under the power lines in the area. The company said the fire got "dangerously close" to the lines, which raised concerns. Power is expected to be restored by the end of the day in the impacted areas.
