Happy Valentine’s Day. This is Mark Staples with the Gallatin National Forest Avalanche Advisory issued on Friday, February 14 at 7:30 a.m. Grizzly Outfitters, in partnership with Friends of the Avalanche Center, sponsors today’s advisory. This advisory does not apply to operating ski areas.
AVALANCHE WARNING
The Gallatin National Forest Avalanche Center is continuing a Backcountry Avalanche Warning for the mountains around Cooke City. Heavy snowfall and strong winds have created highly unstable conditions. Natural and human triggered avalanches are very likely. The avalanche danger is rated HIGH in the mountains around Cooke City. Very dangerous avalanche conditions exist. Travel in avalanche terrain is not recommended and avalanche runout zones should be avoided.
This warning will either be terminated or updated by 6:30 AM on Saturday, February 15.
Yesterday another 6 inches of snow fell near Cooke City, 2-4 inches near Big Sky, 1-2 inches near Bozeman, and a trace of snow near West Yellowstone. With this snow came very strong winds which were blowing 30 mph gusting 50-60 mph from the W and SW. Gusts on Flanders Mountain in Hyalite Canyon reached 87 mph. This morning winds eased a little but should increase again and blow 15-20 mph from the SW and gust 30-50 mph. Temperatures were teens F this morning and will rise into the mid to upper 20’s F today. Snowfall will return late this morning. 5-7 inches should fall near Cooke City, 3-5 inches near West Yellowstone and Big Sky, and 1-2 inches near Bozeman.
Cooke City
Continued snowfall and strong winds will keep the snowpack near Cooke City close to its breaking point. On most slopes the new snow and wind-blown snow alone can produce avalanches. To make matters worse many slopes, especially ones on the southern half of the compass have a thin layer of weak facets on top of an ice crust. This layer is buried 2-3 feet deep and was responsible for an avalanche that my partner and I remotely triggered on Tuesday (photo). Near Round Lake a snowboarder was buried in an avalanche on Tuesday, and on Wednesday snowmobilers triggered a slide in that area.
Recent avalanche activity, more snow, and more wind are clear signs of very dangerous avalanche conditions. Avoid any slope over 30 degrees or the run out zones of these slopes (video). Today avalanches should occur on their own or will be triggered by a skier or rider and the avalanche danger is rated HIGH.
Madison Range Southern Gallatin Range
Lionhead area near West Yellowstone
The mountains from Big Sky to West Yellowstone have a weak layer of faceted snow buried about 2 feet deep. This layer is weakest and can be found mostly on open slopes sheltered from the wind. Triggering an avalanche on these slopes is likely (photo). Last weekend skiers and snowmobilers triggered slides on this layer both north and south of Big Sky, on Lionhead near West Yellowstone, and near Beaver Creek north of Quake Lake. This layer will continue to produce avalanches. Some slopes do not have this layer, and fresh wind slabs will be the main concern. With a sensitive weak layer on some slopes and fresh wind slabs on many others, human triggered avalanches are likely and the avalanche danger is rated CONSIDERABLE.
Bridger Range Northern Gallatin Range
Yesterday a skier near Mt Blackmore in the northern Gallatin Range was literally picked up and tossed onto his back by a gust of wind. These winds (photo) scoured many slopes and formed hard wind slabs on others. The snowpack has a weak layer 1.5 to 2 feet deep on some slopes and it is worth looking for this layer. However, on many other slopes it is either much stronger or non-existent. Today wind loaded slopes steeper than 35 degrees have a CONSIDERABLE avalanche danger. All other slopes have a MODERATE danger.
US: Six Avalanche Fatalities since Saturday
From the CAIC website: Avalanches have killed six people in the western US since February 8. Avalanches killed two people in Utah on 2/8 and 2/9. Two separate accidents killed two people in Colorado on 2/10. Two people were killed in a single accident on 2/11 in Oregon.
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.
KING AND QUEEN OF THE RIDGE
Saturday, February 15th is the 12th Annual King and Queen of the Ridge Hike/Ski-a-thon fundraiser to support avalanche education in southwest Montana. Collect pledges for one, two or the most ridge hikes you can do in the five hours of competition. 100% of the proceeds go to the Friends of Gallatin National Forest Avalanche Center. Kids and families are encouraged to hike too! Hike as an Individual or Team. Make a Pledge. Sign Up. More Info.
EVENTS/EDUCATION
February 20, BOZEMAN: Thursday, 6:30-8:00 p.m., REI, Women’s Specific Avalanche Awareness lecture. Pre-registration is required: www.rei.com/stores/bozeman.html
February 22, BIG SKY: Saturday, 10 a.m. – 2 p.m., Beehive Basin Trailhead, Companion Rescue Clinic. In partnership with Grizzly Outfitters. Space is limited and pre-registration is required. https://ticketriver.com/event/9964
February 22, WEST YELLOWSTONE: Saturday, 7:00-8:00 p.m., Holiday Inn, 1 –hour Avalanche Awareness for Snowmobilers lecture.
More information our complete calendar of events can be found HERE.