Good Morning. This is Doug Chabot with the Gallatin National Forest Avalanche Advisory issued on Sunday, January 3, at 7:30 a.m. Javaman, in cooperation with the Friends of the Avalanche Center, sponsor today's advisory. This advisory does not apply to operating ski areas.
Since yesterday morning 2 inches of snow fell in Taylor Fork and the Bridgers while everywhere else got a trace to 1 inch. Winds have calmed significantly and are currently blowing out of the west at 5-15 mph with mountain temperatures in the high teens. Today we'll see mostly cloudy skies, light westerly winds and temperatures reaching the mid 20's. No snowfall is expected the next few days either.
The southern Madison and southern Gallatin Ranges, the Lionhead Area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
The southern mountains have an extremely weak snowpack. Over a foot of new snow fell Thursday and Friday prompting yesterday's Avalanche Warning. During the last few days, natural and human triggered avalanches were seen in the Taylor Fork, Lionhead and Cooke City areas. Some of these slides were triggered from adjacent slopes and also from the flats. Here's a photo of a slide released from the bottom of a hill at Lionhead. These are signs of very unstable conditions. Everything is sliding on sugary, faceted snow 1-2 feet deep. You may see a few naturals today and I expect you could easily trigger a slide. Getting an avalanche to release from flat terrain is scary and dangerous. Stay clear of runout zones and be aware of low-angled slopes that are connected to steeper terrain since avalanches can propagate over long distances. For today, the avalanche danger is rated HIGH on all recently wind-loaded slopes or any slope steeper than 35 degrees. Lower angled terrain has a CONSIDERABLE danger.
The northern Madison Range:
The snowpack near Big Sky is weak and unstable. These mountains have not gotten the snow load the southern mountains received, but are still avalanching with human triggers. Yesterday, a skier was able to release an adjacent slope on Yellow Mountain as he skinned uphill. Facets broke 18 inches deep and put debris 700-1,000 feet down the path. Check out a photo of the crown line. In Beehive Basin skiers got widespread collapsing too, a clear warning of avalanche potential. Anytime someone triggers an avalanche remotely, I get extra worried. These are dangerous times and I recommend touring on slopes less than 30 degrees (aka. avalanche terrain) while being hyper aware of not traveling under steeper terrain. For today, the avalanche danger is rated CONSIDERABLE on all slopes.
The Bridger and northern Gallatin Ranges:
It's still easy to find weak, faceted snow in the Bridger and northern Gallatin Ranges. On Thursday Eric, Mark and I couldn't help but find it on the east and west sides of the range near Bridger Bowl. Skiers yesterday triggered a wind slab on these facets north of the ski area. Although it was skier triggered, no one was caught. Yesterday on Mt Blackmore, skiers got clean shears with their stability tests one foot under the surface and opted to stay on mellow terrain. Two days ago other skiers saw evidence of avalanches on wind-loaded terrain in this area too. Unlike the southern areas which have a widespread and uniform instability, the mountains around Bozeman have lots of variability, which means you'll need to be thoughtful and meticulous in your snowpack assessments. Mount Ellis' slopes hold facets to the ground, much like the west side of the Bridgers while the snows near Hyalite Peak are more consolidated and supportable. For today our main avalanche concern is on wind-loaded slopes which have a CONSIDERABLE avalanche danger. Slopes not affected by the wind have a MODERATE danger.
Eric will issue the next advisory tomorrow morning at 7:30 a.m. If you get out in the backcountry give us a call or email with your observations. You can reach us at 587-6984 or email us at mtavalanche@gmail.com.
LIONHEAD WEATHER
Our weather station on Lionhead is now running and reporting weather at 4 a.m. and 4 p.m. We haven't installed the snow sensor yet, but you can check out temperature and wind speed.
AVALANCHE EDUCATION
1. BOZEMAN
Level 1: 7-10 January, Montana Outdoor Science School is offering a Level 1 Avalanche Course. Instructors are Angela Patnode and Jay Pape. For more information, contact Montana Outdoor Science School at 406-582-0526.
2. BOZEMAN
Level 1: American Avalanche Institute is offering a Level 1 Avalanche Course January 22-24, 2010 at Bridger Bowl. Get more information and register at: www.americanavalancheinstitute.com
3. FOUR CORNERS
Rescue Lecture: On Tuesday, 26 January, the Gallatin Valley Snowmobile Association is having it annual Chili Feed at 6:30pm in the Groomer Shack. At 7:00 there's a free Avalanche Rescue Talk. http://www.mtavalanche.com/workshops/calendar
4. BOZEMAN
Basic Avalanche Workshop: The Friends of the Avalanche Center and MSU are offering a Basic Avalanche Awareness Class the evenings Wed, Thur, 27 & 28 January with a field day on Saturday, 30 January. $25 donation. No sign up required. http://www.mtavalanche.com/education/classes/basic