This is Doug Chabot from the Gallatin National Forest Avalanche Center with an early season Avalanche Information Bulletin issued at 12 noon on Friday, November 20. Northern Lights Trading Company, in cooperation with the Friends of the Avalanche Center, sponsor this bulletin. This information will be updated as conditions change. Uphill traffic is not allowed at Big Sky or Moonlight Basin Ski areas. Bridger Bowl has backcountry conditions since the ski area is not open.
No new snow has fallen since our last bulletin on November 12. Ridgetop winds were strong last weekend, but calmed throughout the week. Currently they are blowing west to southwest at 15-25 mph. Today a front is approaching from the southwest bringing cloudy skies. Tonight and tomorrow morning snowfall is expected with another storm arriving later Sunday. I'm expecting a total of 4-6 inches of new snow in the mountains by late Monday. Temperatures will dip into the teens and rise into the high 20s over the weekend and winds will continue to be breezy out of the west.
Last Thursday 12-16 inches of new snow fell, immediately followed by strong winds over the weekend. Skiers were out in droves in the Bridger Range and a few folks triggered small avalanches. One slide was down low in Slushman's Drainage when a skier triggered a steep, windloaded slope that buried him to his chest inside the gully. Another slide was triggered in a thin, rocky area off the ridge while a third avalanche was noted on the east side of Ross Pass. See photo at: http://bit.ly/6oowjj. Small avalanches can be just as deadly as big ones. Being swept over rocks, into trees, off cliffs or into deep gullies is hazardous to your health.
With new snow and wind this weekend, soft slabs will form at the ridgetop level. Wind affected areas will have the most unstable snow. If the forecast is wrong and we get more accumulation than anticipated, then expect more avalanche activity.
The mountains currently have 18-28" of a settled base. The least amounts are found around West Yellowstone with the higher depths in the Bridger Range, northern Gallatins and Cooke City areas. Once we get a bit more snow we'll start issuing daily advisories along with danger ratings.
AVALANCHE EDUCATION
Basic Avalanche Awareness at MSU (12 Hour Course):
Evening Sessions: December 2 and 3, 2009, 7:00pm to 9:30pm, at MSU in Leon Johnson Hall, room 339.
Field Session: December 5, 2009, 9:15am to 3:00pm, at Bridger Bowl Ski Area.
Cost for the entire workshop is $25.00 ($5 each evening and $15 for the field session). Registration is not required for the evening sessions, but is required for the field session, which can be done at either of the evening sessions.
Basic Avalanche Awareness for Snowmobilers (12 hour Course):
Bozeman:
Evening Sessions: Wed and Thursday, December 2 and 3, 2009, 7-9:30 pm; Team Bozeman
December 13 is an all day field session, exact location TBD. ($30 Donation)
No Registration Required.
A full listing of the avalanche classes offered in southwest Montana can be found on the education page of our website: http://www.mtavalanche.com/education
If you get out in the backcountry give us a call or send us an email with your observations. You can reach us at 587-6984 or at mtavalanche@gmail.com.