Good morning. This is Mark Staples with the Gallatin National Forest Avalanche Advisory issued on Saturday, February 2 at 7:30 a.m. Montana Import Group, in partnership with the Friends of the Avalanche Center, sponsors today’s advisory. This advisory does not apply to operating ski areas.
Snow showers yesterday morning produced 2-4 inches in most areas. This morning temperatures were in the teens F and westerly winds were blowing 10-15 mph with gusts 20-30 mph. Today will be mostly sunny with temperatures in the low 30s F. Westerly winds will blow 10-25 mph.
Bridger Range Gallatin Range Madison Range
Lionhead area near West Yellowstone Cooke City
Today will have perfect conditions for human triggered avalanches – recent heavy snow, lurking weaknesses in the snowpack combined with sunshine and good powder. What worries me is that many slopes are stable, and signs of instability may not be obvious before triggering an avalanche.
However, mother nature gave us some good clues yesterday.
- Ace Powder Guides spotted 10 recent natural avalanches on S facing slopes on Kirkwood Ridge near West Yellowstone. These were 70-100 feet wide and broke about 1.5 feet deep.
- Gallatin N.F. Snow Rangers remotely triggered a small slide along Beaver Creek on a SE facing slope. It was 12 inches deep and about 25 feet wide.
- Two slides were remotely triggered on a W facing slope in Beehive Basin. Both were about 1-1.5 feet deep and 50 feet wide.
- The Moonlight Basin Ski Patrol spotted a small slide on Fan Mtn. in a “seemingly shallow faceted area” with a heavy load of new snow.
- Eric spotted a natural avalanche (photo) on Mt Blackmore and experienced collapsing and cracking on SE facing slopes in areas that previously had a thin snowpack (video).
- Two days ago on Mt. Ellis, Eric experienced widespread collapsing and cracking (photo).
- I saw one small slide near McAtee Basin involving just the new snow on a N aspect, then experienced collapsing and cracking on a S facing slope along Buck Ridge (video).
- A skier near Cooke City observed shooting cracks in the snowpack at lower elevations and significant wind drifting at higher elevations (photo).
There are several avalanche problems today. At higher elevations in many places the snowpack is deep and strong, and the avalanche problem is fresh wind slabs and drifts. Fortunately these are usually easy to see and avoid. Another trickier problem is weak facets under the new snow. These facets exist on many slopes that previously had less than 2.5 feet of snow due to low elevation or wind scouring. They also exist on slopes that were sheltered from strong wind events in January and developed a thin layer of near surface facets.
These avalanche problems are confusing and tricky. The simple solution is to avoid any fresh wind slabs and drifts. Also, assume every slope has weak facets under the new snow until you have enough evidence to convince yourself they will be absent from the slopes where you hope to ski or ride. This is not an impossible task but will require careful observations.
Many slopes can easily produce human triggered avalanches today and many will not. These are dangerous avalanche conditions that require careful snowpack evaluations to ski or ride in avalanche terrain. For today the avalanche danger is rated CONSIDERABLE.
Eric 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.
Avalanche Accident
A skier was caught and fully buried in an avalanche in the Centennial Mountains along the Montana/Idaho border. His partners were all in safe locations watching him descend, all had rescue gear, and uncovered him in about 3 minutes – good job! He was injured as the avalanche carried him through trees fortunately he did not sustain serious injuries. Watch this video from the skier who was caught. See photos of the crown and debris.
February 16: 11th Annual King and Queen of the Ridge
The 11th Annual King and Queen of the ridge Hike/Ski-a-thon fundraiser is Saturday, February 16. The event supports avalanche education. Enter as an individual or a team. Collect pledges for the number of hikes you can do in five hours. Kids and families are encouraged to hike too! Prizes will be awarded to the most hikes (1st, 2nd, and 3rd); most money raised, most laps for a team, most money raised for a team. More Information / Registration Form
In Bozeman, on Wednesday, February 6, REI is hosting a 1-hour Avalanche Awareness lecture for Women. Space is limited and registration is required: http://www.rei.com/event/47916/session/64605
The Friends are teaching a free Companion Rescue Course in Big Sky, at Grizzly Outfitters, on Friday, February 8 from 6-8 p.m., followed by a field session the next day from 10 a.m. to 2 p.m. Space is limited and pre-registration is required: https://ticketriver.com/event/5830-companion-rescue-clinic-for-skiers-&-boarders