9 December 2007 Good Morning. This is Ron Mangled Meniscus Johnson with the Gallatin National Forest Avalanche Advisory issued on Sunday, December 9 at 7:30 a.m. The Bridger Bowl Ski Area, in cooperation with the Friends of the Avalanche Center, sponsor todays advisory. This advisory doesnt apply to operating ski areas. MOUNTAIN WEATHER A dusting, at best, of new snow fell in the mountains of southwest Montana during the past 24 hours. This morning at 4:00 am mountain temperatures were between 0 and 10 degrees F. Ridgetop winds, which had been easterly during the past 2 days switched to the north-northwest early this morning and were blowing 10-20 mph. Today skies will be partly cloudy, northwesterly ridgetop winds will blow 10-20 mph, mountain temperatures will reach the teens and Pittsburg will beat New England 21 to 17. Late tonight clouds will increase as a weather disturbance moves into southwest Montana. Tomorrow snow is likely. Northwest flow aloft will enhance snowfall amounts over the northern mountains. SNOWPACK AND AVALANCHE DISCUSSION The Bridger Range and northern Gallatin Range: Yesterday ski patrollers at Bridger Bowl noted that recent easterly winds had scoured the east side of ridge crests and thin wind slabs had formed on the west side of the Bridger Range. The wind slabs didnt readily fracture but still warrant caution especially on steep slopes. Today a MODERATE avalanche danger exists on recently wind-loaded slopes. Non wind-loaded slopes have a LOW danger. The northern Madison Range: Yesterday several folks enjoyed good skiing in the mountains just north of Lone Peak, near Big Sky. They reported good snow stability on non wind-loaded slopes. Their stability tests revealed a layer of faceted snow near the ground. No clean fractures occurred on this layer and they didnt notice any collapsing or cracking of the snowpack. Ski patrollers at Big Sky did notice the snowpack collapsed and cracked near treeline. Their observations mean that faceted snow near the ground remains a concern and avalanches are possible on non wind-loaded slopes. Recent avalanche activity on wind-loaded slopes on Lone Peak and Pioneer Mountain indicate these slopes warrant extra caution. Today a CONSIDERABLE avalanche danger exists on wind-loaded slopes, while non wind-loaded slopes have a MODERATE danger. The southern Gallatin and southern Madison Range, the Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range: Faceted snow near the ground in the mountains around West Yellowstone and faceted snow in the middle of the snowpack in the mountains around Cooke City produced widespread avalanche activity early last week when they were rapidly loaded with several inches of snow water equivalence. Its been at least four days since a significant load of snow fell in these areas and the snowpack is less likely to produce natural avalanche activity. However, weaknesses associated with buried layers of faceted snow commonly persist and human triggered avalanche remain a concern. Today a CONSIDERABLE avalanche danger exists on all slopes in the mountains around Cooke City and West Yellowstone.