Good morning. This is Doug Chabot with the Gallatin National Forest Avalanche Advisory issued on Thanksgiving Day, November 27 at 7:30 a.m. Today’s advisory is sponsored by Cooke City Motorsports in partnership with the Friends of the Avalanche Center. Backcountry conditions exist within the ski area boundary of Bridger Bowl and this advisory is relevant to that area. All the other ski areas are closed to uphill travel.
AVALANCHE WARNING
We are continuing a Backcountry Avalanche Warning for our entire advisory area. Heavy snowfall with strong winds created widespread instability. Human triggered and natural avalanches are likely. The avalanche danger is rated HIGH in the Bridger, Gallatin and Madison Ranges, the Lionhead area outside West Yellowstone and 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 be updated or terminated by 6:30 a.m. on Friday, November 28.
AVALANCHE FATALITY
I am saddened to report that a snowmobiler died in an avalanche outside Cooke City yesterday. The victim, a 31 year old male from North Dakota, remotely triggered a slide on the southwest side of Henderson Mountain in the Miller Creek drainage. He was a very experienced rider and had been coming to Coke City for the last eight years. The victim remotely triggered the avalanche from a flat are and was buried about five feet deep when the steeper slopes above him released. He and his partner had rescue gear and the partner made a heroic effort to dig him out, uncovering his head in about 20 minutes. CPR was unsuccessful and Cooke City SAR responded within 10 minutes of the call-out and helped evacuate the victim. The avalanche broke on facets at the ground. The crown was 37 degrees steep and broke two to three feet deep, 300 feet wide and 500 feet vertical. Mark Staples was able to do a site investigation late yesterday afternoon and will write a detailed report in the coming days.
Early yesterday morning the snow stopped falling. Ridgetop winds blew westerly at 25-35 mph during the day and last night, lower elevation, mid-mountain winds increased from the south to 35 mph. Mountain temperatures have warmed into the upper 20s under partly cloudy skies. Today will remain partly cloudy and windy. No new snow is expected in the next 24 hours and temperatures will rise to above freezing in many areas.
Bridger Range Gallatin Range Madison Range
Lionhead area near West Yellowstone Cooke City
An avalanche warning and an avalanche fatality should grab everyone’s attention. A poor snowpack structure is causing avalanches throughout our advisory area. Weak, sugary, faceted crystals at the ground are doing a lousy job of supporting the new, dense snow that fell in the past few days. The snowpack is like a loose cannon as it adjusts to this new load. Besides the avalanche fatality there were widespread incidents of natural and human triggered slides. I was at Bridger Bowl yesterday tagging along with the ski patrol and found very unstable snow. Every turn produced shooting cracks with loud whumphs which sounded like rolling thunder as I skied. With instability like this it is pertinent to stay out of avalanche terrain. Many folks skiing at Bridger Bowl erroneously thought it was safe because of their familiarity of the area, however, no avalanche mitigation has been done and the avalanche danger is the same as everywhere else: HIGH. To help explain the avalanche warning I added a few photos to the website and made a video.
The winds will be moving the new snow at all elevations creating wind drifts which will easily avalanche. Avoid avalanche terrain and runout zones today and be especially mindful about remotely triggering a slide. If the snow collapses the fracture will travel uphill and avalanche at its steepest point and bury you. Remote triggers are scary and deadly.
If you get out please let us know what you find. Pictures, snowpits, and a general narrative of conditions are super helpful. Drop us a line at mtavalanche@gmail.com.
Sharing our advisories and photos. Yesterday we launched the ability to share the best parts of our website. Social media icons on the page allow you to share individual pictures and the daily advisory.
Have a Smartphone or Tablet? The Friends of the Avalanche Center just published two FREE apps so you can get the latest avalanche information, videos and photos: iOS 8 GNFAC App; Android app
AVALANCHE EDUATION:
Take a look at our Education Calendar for all our classes being offered.
MSU - Introduction to Avalanches with Field Course
The workshops are held on Wednesday and Thursday evenings, with a field course on Saturday. Different topics are presented each evening. Topics include: avalanche terrain recognition, the affect weather has on avalanche hazard, the development of the mountain snowpack, decision making skills, and basic search and rescue procedures.
December 3, 4 and 6 or 7, 2014: https://www.ticketriver.com/event/13089
Snowmobiler Introduction to Avalanches with Field Course
Five hours of lectures are followed by a full day field course. Topics covered include: avalanche terrain recognition, the affect weather has on avalanche hazard, the development of the mountain snowpack, decision making skills, and basic search and rescue procedures.
West Yellowstone: Dec 18 and 19, 2014: https://www.ticketriver.com/event/12955