A Canadian cold front sliding south along the continental divide brought some relief from the heat and cleared out much of the smoke plaguing Montana Wednesday, but the wildfires raging along the Idaho/Montana border went unabated as gusty winds fanned the flames, testing both states’ fire lines.
In central Idaho the Moose Fire, burning in the Salmon-Challis National Forest north of Salmon, has now grown to 107,523 acres, making it the largest wildland fire currently burning in the United States. Firefighters reported extreme fire behavior Wednesday with individual and group tree torching and wind-blown embers igniting spot fires ahead of the existing flame front.
At 9 p.m. Wednesday the fire crossed the Ridge Road, triggering evacuations north of Salmon. The Moose Fire also threatens U.S. Highway 93, the main route connecting Salmon with southwestern Montana. Thus far fire crews have been able to keep the highway open, in some instances needing to remove burned debris from the roadway to keep it passable to both fire traffic and the public.
Increased cloud cover and even a potential for showers is forecast for the area through Friday, but fuels remain critically dry and any thunderstorms may produce strong winds contributing the fire’s behavior.
Any relief provided by the weather is expected to be short lived. From Saturday on temperatures in the area are forecast to gradually increase, and the Moose Fire’s activity is expected to remain moderate to high in the week ahead.
Trail Ridge Fire
The largest forest fire in Montana is burning along the Continental Divide, 22 miles northwest of Wisdom. The Trail Ridge fire grew by nearly 2,000 acres Wednesday as high winds pushed the flames to encompass more than 12,500 acres.
The fire is burning in a remote and rugged terrain just southwest of the Anaconda-Pintler Wilderness Area, with abundant standing dead trees and heavy ground fuels originating from a fire that burned in 2000.
Fire crews are working to identify potential control locations in the difficult terrain utilizing natural barriers, existing trails and roads, and are beginning to prepare containment lines along the west and north sides of the fire. No structures are currently threatened by the Trail Ridge Fire and none have been destroyed
Kootenai River Complex
Comprised of four distinct but closely adjacent fires, the Kootenai River Complex in the Selkirk Mountains northwest of Bonners Ferry, Idaho grew by more than 1,200 acres yesterday and has now consumed a total of 13,705 acres of timberland just south of the Canadian border and roughly 15 miles west of the Montana border.
Fire crews are working in tandem with heavy equipment to construct a fireline through some areas of slash debris left behind by a prior timber harvest. Forty-two structures are currently threatened by the Kootenai River Complex fires; however, fire crews have finished setting up pumps, hoses, and sprinklers for structure protection in the threatened areas. No structures have been destroyed at this point in time.
While temperatures in the region have moderated no precipitation is forecast for the area in the immediate days ahead. Helicopters will continue to deliver buckets of water along the east side on the fires if wind and smoke conditions allow.
Weather forecasters are hopeful that the incoming Canadian cold front will bring a significant chance for showers to the mountains and valleys along the continental divide on Friday. It will also bring increasing northeasterly winds and the potential for below normal temperatures for the first time in several weeks.
“We could also see light snowfall at the highest peaks in Glacier National Park by Friday morning," the National Weather Service forecast predicts. "Widespread freezing temperatures are expected for the higher valleys along the divide east of Highway 93 in western Montana. For valley locations along and west of Highway 93 lows Saturday morning are expected to be in the mid- to upper-30s with a good chance for seeing widespread frost."
However, the relief is not expected to last very long. A pesky ridge of high pressure is expected to re-establish itself over the Northern Rockies by Sunday. Temperatures are expected to warm again through the first half of next week to a few degrees above seasonal averages, but not as hot as what we’ve recently been experiencing.
This article originally appeared on Great Falls Tribune: Cooler temps bring relief, but Montana, Idaho wildfires rage