Good morning. This is Doug Chabot with the Gallatin National Forest Avalanche Advisory issued on Black Friday, November 28 at 7:30 a.m. Today’s advisory is sponsored by Grizzly Outfitters 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.
The temperature swings are giving me whiplash. At 5 a.m. most mountain locations were near or above freezing under mostly cloudy skies with west to southwest winds blowing 20-35 mph. Today temperatures will remain warm, clouds will increase, winds will remain the same and 1-2 inches of snow will fall in our southern mountains late tonight. An arctic cold front moves in tomorrow chilling us back into the single digits.
Bridger Range Gallatin Range Madison Range
Lionhead area near West Yellowstone Cooke City
The Avalanche Warning has expired, but the snowpack is a far cry from giving us a green light. The facets at the ground are weak and problematic. The mountains have up to four feet of snow sitting on them and over the last three days this weak layer collapsed and avalanched on many slopes. A snowmobiler was killed on Wednesday outside Cooke City when he remotely triggered a slide on this layer which buried him under five to six feet of debris (read a paragraph about the accident at the end of the advisory). Signs of instability like cracking, collapsing and natural avalanches are declining, but it’s still easy to trigger avalanches.
The snowpack structure is poor as weak facets struggle to support slabs of storm snow and windblown snow (snowpits). Everyone should dig a quick pit to see what we’re talking about. The facets are easy to find and a quick swipe of the hand shows their weakness. Today is a day to be conservative. Although prolonged above freezing temperatures can help stability, this is not our current case since the warming will be short-lived.
An unstable snow structure, recent avalanche activity and continued wind-loading point to a CONSIDERABLE avalanche danger throughout our advisory area today.
AVALANCHE FATALITY IN COOKE CITY
(Video, Five Photos, Snowpit)
A snowmobiler died in an avalanche outside Cooke City on Wednesday. The victim, a 31 year old male from North Dakota, remotely triggered a slide on the southwest side of Henderson Mountain off the Miller Road. He was a very experienced rider and had been coming to Cooke City for the last eight years. The victim remotely triggered the avalanche from a flat area which released steeper slopes and buried him under five to six feet of debris. 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 and will write a detailed report in the coming days.
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