Good morning. This is Doug Chabot with the Gallatin National Forest Avalanche Advisory issued on Tuesday, February 22, at 7:30 a.m. The Cliff Gullett Memorial Fund in cooperation with the Friends of the Avalanche Center, sponsors today’s advisory. This advisory does not apply to operating ski areas.
Yesterday morning another one to two inches fell in most ranges, but snow showers outside West Yellowstone dropped five inches of new snow. Winds are increasing out of the west to southwest and are currently blowing 20-35 mph with temperatures in the single digits. A storm is slated to arrive early this afternoon and last into Thursday. In the next 24 hours I expect six to eight inches of new snow in the mountains with strong westerly winds and temperatures only rising into the high teens before dropping to the low single digits tonight.
The Bridger, Madison and Gallatin Ranges, the Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
We’ve had a snowy week. Since last Wednesday 1.5 to over two feet of snow has fallen throughout southwest Montana. West to south winds have drifted this snow and created instabilities. Yesterday, natural slides from wind-loading were noted on Buck Ridge and also on Lone Peak. The Big Sky and Moonlight Ski Patrols found touchy soft slabs which were easily ski cut. A snowmobiler in Taylor Fork also triggered a wind slab and skiers on Mt. Blackmore stuck to sheltered slopes since slabs were building throughout the day (photo). The Bridger Bowl Ski Patrol saw plumes of snow cross loading slopes at mid elevations, so don’t get fooled into thinking wind slabs are only near the ridgetop.
The recent avalanche activity has been limited to the new/old snow interface. But a layer of small-grained facets is still an issue on isolated and seemingly random slopes. This layer is buried under two to three feet of snow. In Lionhead yesterday, it caught me by surprise when I got it to fracture in my last snowpit of the day (video) (photo) (snow pit profile). We could not get it to break in Taylor Fork last week, nor in Beehive Basin on Sunday, but Mark and others did find it up Hyalite in the northern Gallatin Range on the 17th. This layer is strengthening, but some slopes, especially those with the added stress of wind drifts, could still fracture.
Ridgetop and lower elevation winds are still drifting and cross loading slopes. These are likely spots where skiers and snowmobilers can trigger an avalanche today. There’s also the added possibility of slides breaking into deeper layers on a few select slopes—not a pretty thought. For today, the avalanche danger is rated CONSIDERABLE on all wind-loaded terrain. Slopes without a wind-load have a MODERATE danger. Knowing that there are still a few slopes with a deeper instability means I’ll be digging at least three feet down to look for it. Sure, it’s more work, but like flossing, it’s preventative behavior.
I will issue the next advisory tomorrow morning at 7:30 a.m. If you have any snowpack or avalanche observations, drop us a line at mtavalanche@gmail.com or call us at 587-6984.
3rd Annual Montana Ale Works Fundraiser
Tuesday, March 1 at 6:00 p.m. in the Railcar at Ale Works in Bozeman
Cost: $25 to benefit the Friends of the Avalanche Center
Details: Chef Roth at Montana Ale Works is creating tapas style servings that will be paired with select beer from Lone Peak Brewery. More information HERE.
Pinhead Classic
The 30th Annual Pinhead Classic on is Saturday, March 5th. “Gangsters and Flappers” is this year’s costume theme, so come dressed up to race, socialize and wind great prizes. Registration is $30 but get you all sorts of cool stuff. All proceeds benefit the Friends of the Avalanche Center. Check out the website http://pinheadclassic.com for details.