August 18, 2022 - Multiple Fires in Idaho Forests

Fires in Idaho

Dry weather, low humidity, gusty winds, and lightning strikes sparked multiple fires in the forests of central and southern Idaho in July and August 2022. The Moderate Resolution Imaging Spectroradiometer (MODIS) on board NASA’s Aqua satellite acquired a true-color image of fires and smoke in Idaho on August 16.

Each red “hot spot” marks an area where the thermal bands on the MODIS instrument detected high temperatures. When combined with typical smoke, as in this image, such hot spots mark actively burning fire. At least ten different fires were burning in the grass, timber, and heavy forest across the region on that date. These include, roughly from north to south, the Moose Fire, Pretty Fire, Petes Fire, Indian Ridge Fire, Dismal Fire, Wolf Fang Fire, Porphyry Fire, Woodtick Fire, Norton Fire, and Four Corners Fire. Each will be briefly described. The smaller fires are not visible in the image while the largest may have more than one hot spot, as fires often spread on several fronts.

The Moose Fire, sitting in the northeast, is the largest fire. It started July 17 about 17 miles north of Salmon, Idaho. This blaze likely has been caused by humans and is under investigation. As of August 17, more than 1,000 personnel are working to suppress the fire, which has charred about 78,084 acres and is only 34 percent contained. Rafts are being used to shuttle firefighters and equipment across the Salmon River to work the fire. Also nearby are the Pretty Fire and Petes Fire. The Pretty Fire started on August 15 near the intersection of Panther Creek Road and Salmon River Road. It was contained on August 16 and has not grown. On August 16, a lightning strike ignited Petes Fire near Moyer. As of August 17, it was only about 5 acres in size. Rising temperatures and low relative humidity, along with temperatures in the mid-90s, spur fire growth.

The Indian Ridge Fire was started by lightning strike on July 7 in the Indian Creek drainage in Idaho’s Selway-Bitterroot Wilderness. As of August 17, it has grown to approximately 4,000 acres. It is burning five miles from the Idaho/Montana border and is approximately 30 miles southwest of Darby, MT. Area and trail closure is in effect. The fire is burning in very steep, rugged, and remote terrain with heavy surface fuels and dead standing timber making access for firefighters difficult and dangerous. According to InciWeb Incident Information System, fire managers are using a point protection strategy on this fire, aimed at preventing any critical wilderness infrastructure from being negatively impacted by the fire. In a threatened campground, crews wrapped signs and tables with flame resistant foil and installed sprinklers on the road bridge.

Lighting strikes ignited two fires in the Frank Church-River of No Return Wilderness of the Payette National Forest during the second week of July. This area is south and west of the Indian Ridge Fire. The first fire, Mosquito Ridge, was confined to a single tree and was completely put out on July 25. The second fire is called the Dismal Fire and continues to burn in the headwaters for the Dismal Creek Drainage. As of August 17, this fire has reached 1,371 acres in size. It is a low-intensity fire primarily burning in underbrush under standing trees. The InciWeb report states “The Dismal Fire is being managed to allow for naturally occurring wildfire to accomplish its ecological role.” In addition, a point/zone protection strategy is being utilized to protect valuable areas at risk.

The Wolf Fang Fire, also started by lightning, was first reported July 13 about four miles northeast of the confluence of Big Creek and the Middle Fork of the Salmon River in the Frank Church-River of No Return Wilderness. As of August 17, the fire has reached 1,126 acres and is burning in spruce and fir is located in steep, rugged terrain. It is a low-intensity fire, exhibiting creeping and smoldering behavior in essentially inaccessible territory. With a focus on risk to responders and public safety, the fire is being assessed daily but no active suppression was reported.

On August 11, thunderstorms passed over the Payette National Forest, sparking the Porphyry Fire which burns west of Porphyry Creek high along the ridge from the South Fork of the Salmon River. To date, it has burned 485 acres and closures of parts of the forest are likely as the fire is continuing to expand. Currently the Porphyry Fire is under a suppression strategy with point/zone protection at noted values at risk, such as a burnout of fuels near a bridge that has been successful in protecting that structure. The steep and extremely rugged terrain is characterized as “unforgiving to firefighters”, so additional tactics, such as aerial assists, are being assessed to hold this fire to as small a size as safely possible.

The Norton Fire started on August 1 when thunderstorms tracked through the Salmon Challis National Forest. The lightning fire is located approximately seven miles Northwest of Lower Loon Creek in the Frank Church-River of No Return Wilderness. As of August 17, the fire had burned about 470 acres. An aggressive initial attack was attempted with 25 firefighters and two type 1 helicopters in an attempt to catch it early. However, due to firefighter safety, fire behavior, and difficult access to the fire, a direct attack strategy was changed to point protection. Fire managers continue to monitor fire activity using remote cameras and aircraft.

The Four Corners wildfire flared up about an hour before sunset on August 13, according to an InciWeb report. As of August 17, the blaze has burned about 3,500 acres near Lookout Peak in the West Mountain range west of Cascade on the Payette and Boise National Forests. While no cause has been definitively determined, it is thought to be a lightning holdover from thunderstorms that crossed the area on August 11. The strategy for this fire is full suppression, including aerial support. Boaters on the Cascade Reservoir are cautioned that water-scooping aircraft will be taking water from the reservoir. The water scoopers hold 1,600 gallons of water and it takes 12 seconds to fill the capacity while skimming over the reservoir, so boaters are asked to stay clear of the path of the aircraft.

Image Facts
Satellite: Aqua
Date Acquired: 8/16/2022
Resolutions: 1km (337.3 KB), 500m (226 KB), 250m (656 KB)
Bands Used: 1,4,3
Image Credit: MODIS Land Rapid Response Team, NASA GSFC