The slopes of Mount Jumbo continued to pose a danger for Missoula residents – on and below the mountain – on Saturday, when avalanche experts tested the snowpack’s stability.
On contract with the city, forecasters from the West Central Montana Avalanche Foundation found 4 to 5 feet of unstable snow in some places on the publicly owned mountainside.
The danger, they said, is “very dependent on people staying off the mountain.”
And while Mount Jumbo has been closed to all public access for several days, the avalanche experts found fresh ski tracks on the slope Saturday afternoon.
They found a number of small, naturally occurring slides that had happened in the last 24 hours. Those slides were about 1 foot deep and ran onto the valley floor and into backyards on Lilac Avenue and Holly Street, in the lower Rattlesnake Valley.
While the smaller slides did not endanger homes, they could have buried a person.
Travis Craft, director of the avalanche foundation, said he and his coworkers not only found new snow loaded into gullies and potential avalanche zones within reach of neighborhoods at Jumbo’s base, but they watched as winds blew even more snow into potential start zones.
On the mountain’s ridge, they experienced gale-force, easterly winds of 30 to 40 mph.
In a video released to the public, Craft showed the hardened slab of snow that lies beneath the layer deposited by Friday night’s intense winds, what he termed “a recipe for an avalanche.” He also shot footage of active wind loading.
Conditions remain very similar to those that led to a fatal avalanche down Mount Jumbo five years ago on Feb. 28.
Craft said avalanche conditions should not get worse without a change in the weather. That said, conditions remain dangerous.
According to the National Weather Service, Missoula’s forecast is for frigid temperatures, but little to no new snow overnight on Saturday.
Craft advised residents at the base of Mount Jumbo from Missoula Avenue to Elm Street to stay out of their backyards and to call 911 if they see snow slides.
Residents should also call 911 immediately if they see people on Mount Jumbo. The entire mountain is closed.