8 February 2008 Good morning. This is Ron Johnson with the Gallatin National Forest Avalanche Advisory issued on Friday, February 8, at 7:30 a.m. Yamaha and Team Bozeman, in cooperation with the Friends of the Avalanche Center, sponsor todays advisory. This advisory does not apply to operating ski areas. MOUNTAIN WEATHER Yesterday, 6-8 inches of snow fell in the mountains around Cooke City. The mountains around West Yellowstone got 4-6 inches. The Big Sky area picked up 2-4 inches of new snow, while the mountains around Bozeman were dusted by less than an inch. During the past 24 hours west-southwesterly to west-northwesterly ridgetop winds buffeted southwest Montana. Speeds were 30-50 mph. Similar winds conditions are expected today as another weather system moves across Montana. By tomorrow morning, the mountains around West Yellowstone will get 3-6 inches of new snow. Other areas will get 2-4 inches. Today mountain temperatures will reach the teens to low 20s F. SNOWPACK AND AVALANCHE DISCUSSION The Bridger Range: Yesterday skiers south of Bridger Bowl found stable snow and good skiing on non wind-blasted slopes. Ski patrollers at Bridger Bowl reported snow was blown around near the ridge crest and in the base area. Recently formed wind slabs will be prone to avalanche. Today, a CONSIDERABLE avalanche danger exists on wind-loaded slopes steeper than 35 degrees. Less steep wind-loaded slopes have a MODERATE danger. A LOW avalanche danger exists on non wind-loaded slopes. The northern Gallatin and northern Madison Ranges: Weak faceted snow near the ground persists in the northern Gallatin and northern Madison Ranges. Recent stability tests done on these crystals produced clean fractures especially where snow depths were less than about 3 feet. Yesterday, Karl and his partners investigated wind affected slopes near Cedar Mountain, south of Big Sky. Recently formed wind slabs easily cracked around their skis and they saw a couple of small avalanches on wind-loaded slopes. Ski patrollers at Big Sky, using explosives, triggered several avalanches on wind-loaded slopes. Today, all slopes with recently formed wind slabs have a CONSIDERABLE avalanche danger. Due weak snow near the ground, a CONSIDERABLE avalanche danger also exists on non wind-loaded slopes steeper than 35 degrees. A MODERATE danger exists on less steep non wind-loaded slopes. The southern Madison and southern Gallatin Ranges, the Lionhead area near West Yellowstone, the mountains around Cooke City, and the Washburn Range: On Wednesday, Mark Staples was near Bacon Rind Creek in the southern Madison Range and Doug Chabot was in the mountains just north of Cooke City. They both found a thin weak layer of small grained faceted snow buried 1.5-3 feet deep. This layer produced clean fractures when subjected to a variety of stability tests. Both lads saw recently formed wind drifts and slabs on numerous slopes. These cracked around their skis. The addition of yesterdays wind driven new snow elevated the avalanche danger, which today is HIGH on all wind-loaded slopes steeper than 35 degrees. A CONSIDERABLE danger exists on wind-loaded slopes less steep than 35 degrees. All other slopes have a MODERATE danger.