GNFAC Avalanche Forecast for Fri Nov 30, 2018

Not the Current Forecast

Good Morning. This is Eric Knoff with the Gallatin National Forest Avalanche Forecast issued on Friday, November 30th at 7:30 a.m. This Forecast is sponsored by Alpine Orthopedics and Lawson Dental. This forecast does not apply to operating ski areas.

Mountain Weather

This morning skies are clear and there’s no new snow to report. Temps are in the teens and winds are blowing 5-10 mph out of the E-SE with the exception of Bridger Range where they’re blowing 15-25 out of the E. Today, temps will warm into the 20s F and winds will gradually increase and shift to of the south-southwest. Skies will become cloudy this afternoon as a weak storm system approaches from the south. By tomorrow morning the mountains will likely see 2-4” of new snow.

Snowpack and Avalanche Discussion

The Bridger, Madison, Gallatin Ranges, and mountains around Cooke City

Minimal snow and wind the past few days has helped stability. On Wednesday, my partner and I skied around Beehive Basin and found generally stable conditions photo. This is consistent with other observations from the area. Without widespread persistent weak layers video, instabilities remain isolated to upper elevation slopes previously loaded by west-southwest winds.

Pockets of wind drifted snow will be stubborn and hard to move today, but still need to be assessed carefully. Watch for this problem below upper elevation ridgelines and cross loaded terrain features. As demonstrated by the skier triggered avalanche on Monday, it only takes a small slide to create a potentially dangerous situation video.

Although isolated areas of instability still exist, the snowpack is generally stable and the avalanche danger is rated LOW.

The snowpack in the Lionhead area outside West Yellowstone is shallow and weak.  On Monday, Alex found a 2’ deep snowpack consisting of sugary facets capped by 6” of new snow (photo). His video shows the crumbly nature of the facets and their inability to support much weight. Without new snow and wind the past few days, stability in this area has improved. However, a poor snowpack structure continues to raise red flags. Before committing to steep terrain, assess the snowpack carefully and avoid slopes where dense wind-blown snow rests over weak facets near the ground.

Today, human triggered avalanches are possible on wind loaded slopes which have a MODERATE avalanche danger. Non-wind loaded slopes have a LOW avalanche danger.

Upcoming Avalanche Education and Events

Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.

IDAHO

Tomorrow! Klim Winter Kick-Off and avalanche awareness, Rigby, Idaho

BOZEMAN

December 5, 1-hr Avalanche Awareness, 6-7 p.m. at REI, Bozeman

December 6, 1-hr Avalanche Awareness and Beacon Practice, 6:30-8 p.m. at Story Mill Park

December 11 and 12, Snowmobile Intro to Avalanches w/Field, Holiday Inn, West Yellowstone; more info here

December 12, 1-hr Avalanche Awareness for Snowmobilers, 6-7 p.m. at Yellowstone Motorsports, Bozeman

December 13, 1-hr Avalanche Awareness, 6-7 p.m. at Play It Again Sports, Bozeman

HELENA

December 12, 1-hr Avalanche Awareness, 6-7 p.m. at The Basecamp, Helena

COOKE CITY

Every Friday and Saturday, Rescue Training and Snowpack Update. Friday 6:30-7:30 p.m at the Soda Butte Lodge. Saturday anytime between 10-2 @ Round Lake.

The Last Word

Check out our new “Avalanches and Snowpits” menu item where we list all the reported avalanche activity.

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