GNFAC Avalanche Advisory for Fri Jan 29, 2010

The Madison Range, southern Gallatin Range and the Lionhead area near West Yellowstone:

Both natural and human triggered avalanches have continually occurred in the mountains near and between Big Sky and West Yellowstone since mid December.  This avalanche activity peaked after a significant snow storm on January 6th, but continues with a snowboard triggered avalanche near Big Sky on Tuesday, a large skier triggered slide in the southern Madison Range on Wednesday, and a small snowmobiler triggered slide yesterday near Big Sky.  The avalanche on Tuesday occurred on a slope that slid 2 weeks earlier.  The skier on Wednesday triggered the avalanche from a 30 degree slope that propagated a fracture uphill to a 35 degree slope that broke on facets near the ground.  The avalanche yesterday near Big Sky occurred on a small slope and released as the rider approached the toe of that slope.

Some slopes have stable snow but these are rare.  Recent avalanche activity demonstrates the sensitive and unpredictable nature of the snowpack.  Careful stability evaluations, cautious route finding, and conservative decision making are essential.  Today the avalanche danger is rated CONSIDERABLE on slopes steeper than 35 degrees and MODERATE on less steep slopes.  Watch out for low angle slopes connected to steeper terrain.  Fractures can easily propagate uphill triggering avalanches like the one on Wednesday.

The Bridger and northern Gallatin Ranges, mountains around Cooke City and the Washburn Range:

Stability has improved in the mountains near Bozeman and Cooke City, and many skiers and snowmobilers have found reasonably stable slopes and good riding conditions.  Despite this improvement, buried facets remain in the snowpack and avalanches are a real possibility.  Yesterday in the northern Bridger Range just north of Ross Peak, a snowmobiler triggered an avalanche about 3 ft deep and 75 ft wide.  He and his partner were cautiously making small climbs one at a time.  On the second pass he observed a small tree begin to twitch telling him the slab was breaking.   He made a quick exit off the slope and was not caught.  Skiers just north of Bridger and near Ross Peak found some stable slopes for skiing but also observed fresh wind slabs that they avoided.

Today human triggered avalanches remain possible especially on slopes with recently wind drifted snow and the avalanche danger is rated MODERATE.

Eric will issue the next advisory tomorrow morning at 7:30 a.m. If you get out in the backcountry let us know what you find.  You can reach us at 587-6984 or email us at mtavalanche@gmail.com.

Monday, February 8: MONTANA ALE WORKS BENEFIT DINNER

Mark your calendars: Montana Ale Works is hosting a benefit dinner for the Friends of the Avalanche Center on Monday evening, February 8^th.  Chef Roth Jordan has assembled an amazing five course menu themed "Mountains of the World" with foods from Chile, Montana, France, New Zealand and Germany.  Dinner is limited to 40 seats with the first course served at 6:30 p.m.  Tickets to this event are $75, all inclusive, and available at Montana Ale Works.  More information is available on our calendar or by calling 587-7700.

8^th ANNUAL KING AND QUEEN OF THE RIDGE

The 8^th Annual King and Queen of the Ridge will be held at Bridger Bowl on Saturday, February 13^th.  ALL proceeds go to the Friends of the Avalanche Center who use the money to promote avalanche education in southwest Montana.  Last winter we taught 62 classes reaching over 4,300 people.  You can help raise money to continue this education in 2 ways:

1). Get pledges and hike the ridge.  You don't have to do 20 laps - you can get flat pledges and hike just once!  Or you can test your mettle and try and break John Yarington's record of 27 laps in 5 hours. 

2). Sponsor someone.  If you don't have someone to sponsor, consider sponsoring Mark, Eric or myself since we'll be hiking for dollars. 

You can go to http://www.bridgerbowl.com/events/view_event/15/  for more information and registration forms.

AVALANCHE EDUCATION CALENDAR

1. Big Sky

Moonlight Basin Avalanche Course: Join Moonlight Basin for a comprehensive, two-day and one evening avalanche awareness class.  Thursday, Jan 28^th 5-9:30 p.m. and Friday and Saturday, Jan 29 and 30, 8 a.m. to 4 p.m.  Contact: events@moonlightbasin.com or 406-993-6026

2. West Yellowstone, Holiday Inn

One-hour Avalanche Awareness Class - Saturday, January 30^th - 7 p.m. to 8 p.m.

3. Bozeman

Advanced Avalanche Workshop: The Friends of the Avalanche Center and ASMSU Outdoor Recreation are offering an Advanced Avalanche Workshop on the evenings of February 3 &4 with a field day on Saturday, February 6.  ADVANCED REGISTRATION IS REQUIRED.  For more information or to register contact: friendsofgnfac@gmail.com