THURSDAY, JANUARY 17 Good morning. This is Doug Chabot with the Gallatin National Forest Avalanche Advisory issued on Thursday, January 17th, at 7:30 a.m. Bridger Bowl, in cooperation with the Friends of the Avalanche Center, sponsor todays advisory. This advisory does not apply to operating ski areas. MOUNTAIN WEATHER At my last check at 7 am the Bridger Range picked up 3 inches last night while the rest of southwest Montana got 1 inch. Temperatures are hovering near zero, but will warm into the higher single digits today as strong winds continue from the west-northwest. Yesterday they blew at 25-40 mph and although they have calmed overnight, they will pick up again this afternoon. A moist, vigorous northwest flow is tracking over us bringing more snow. This type of system gives the Bridger Range extra lovin and Im expecting a foot of new snow by morning while the rest of our area gets 3-6 inches. SNOWPACK AND AVALANCHE DISCUSSION The Bridger Range: In the Bridger Range, ten inches of snow by yesterday morning, another three overnight and more today will create increased avalanche danger from strong northwest winds. Balaclava wearing skiers reported stiff winds scouring some slopes while loading others. With temperatures near zero the backcountry had a Denali feel to it. Mark toured into Frasier Lake and found a strong, well bonded snowpack. Consequently, we both expect avalanches to be confined to the new, wind blown snow where you could trigger slides. For today, the avalanche danger on wind-loaded terrain is rated CONSIDERABLE if its steeper than 35 degrees and MODERATE on lower angled terrain. Those rare slopes not affected by the wind will have great skiing and a LOW avalanche danger. The Gallatin Range and Madison Range: Sugary, faceted snow near the ground is still causing us concern in the northern Gallatin and Madison Ranges. An observer reported collapsing and cracking in the Hyalite area on Tuesday while skiers in Bear Basin yesterday got poor stability test results and stuck to low angled terrain. The Big Sky Ski Patrol got a large slide to release on faceted snow buried 2-3 feet deep. It was a few hundred feet wide and as the Snow Safety Director said, these (instabilities) arent everywhere, but its not obvious where it is either. Youll need to be extra sharp and extra cautious. There are slopes that are stable, but as these instances, as well as a snowmobile burial Saturday in Portal Creek show, there are slopes to be worried about too. The southern Madison and Gallatin Range, NOT including Lionhead, only got one inch of snow yesterday, but did have 6-10 inches from the day before. West to northwest winds ripped through these mountains creating fresh wind drifts which you could trigger. This area also has faceted snow 2-3 feet deep which is fracturing in stability tests and, more importantly, avalanching naturally and from human triggers. For today, the avalanche danger is CONSIDERABLE on all wind-loaded slopes and MODERATE everywhere else. The Lionhead area near West Yellowstone, the mountains around Cooke City, and the Washburn Range: The Lionhead area near West Yellowstone and mountains around Cooke City has only gotten 2-4 inches of new snow in the last 48 hours. These mountains have plenty of snow from previous storms to blow around, and given the steady winds, I expect youd trigger slides on steep, wind affected slopes. Faceted snow buried 2-3 feet under the surface is stronger than its northern neighbors, but I believe its still possible to trigger a slide on this layer. I investigated a small slide in Cooke City on Monday that broke on this, while surrounding terrain was more stable. So there you have it--you can still find pockets of unstable snow but these instabilities are not widespread. In fact, skiers near West Yellowstone reported good stability and great skiing on east aspects. For today, the avalanche danger is CONSIDERABLE on all wind loaded terrain steeper than 35 degrees. All other avalanche terrain will have a MODERATE danger.