GNFAC Avalanche Advisory for Thu Mar 15, 2018

Not the Current Forecast

Good Morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Thursday, March 15th at 7:00 a.m. Today’s advisory is sponsored by Knoff Group Real Estate at Pure West and Spark R & D. This advisory does not apply to operating ski areas.

Mountain Weather

Overnight the Gallatin and Madison Ranges picked up 4-6” of new snow. The mountains around West Yellowstone, Cooke City and the Bridger Range received 1-2”. At 5 a.m. temperatures range from the 20’s to low 30’s F and winds are blowing 10-20 mph out of the SW. Today, snow showers will gradually diminish and temps won’t warm much as cooler air moves into the region. Snow shuts off this evening and no snow is expected tonight and tomorrow.

Snowpack and Avalanche Discussion

Overnight the Gallatin and Madison Ranges picked up 4-6” of snow totaling .4-.6” of SWE. This isn’t a huge amount of snow, but it is enough to increase the dry snow avalanche hazard. The new snow was deposited on a firm melt-freeze crust on all but north facing slopes. This will make dry loose avalanches (sluffs) possible in steep terrain. It’s also possible that skiers or riders could trigger small wind slabs in upper elevation terrain leeward to southwest winds. These problems won’t produce exceptionally large avalanches, but they could be hazardous in steep, high consequence terrain. Manage these problems by making smart and conservative terrain selections. Below freezing temperatures will eliminate the possibility of wet snow avalanches.

Today, human triggered slides are possible and the avalanche danger is rated MODERATE.

The mountains around Cooke City, West Yellowstone and the Bridger Range picked up 1-2” of high density snow. This will slightly improve riding conditions, but it won’t do much to elevate the avalanche danger. As temps drop below freezing today, the old snow surface on all but north facing slopes will be firm and locked up. Today, there won’t be much in the way of avalanche hazard other than large cornices. On Tuesday, I observed a few recent avalanches triggered by cornice failure in the mountains around Cooke City (video). Give cornices a wide berth along the ridgelines and limit your exposure time on slopes below (photo, photo).

Today, generally safe avalanche conditions exist and the avalanche danger is rated LOW.

If you get out and have any avalanche or snowpack observations to share, drop a line via our website, email (mtavalanche@gmail.com), phone (406-587-6984), or Instagram (#gnfacobs).

Upcoming Avalanche Education and Events

Events and Education Calendar

LIVINGSTON

March 20, Beer for a Cause Night at Katabatic Brewing, 4-8p.m. A dollar from every pint will be donated to The Friends of the Avalanche Center.

The Last Word

Alex and Eric wrote up a one-page accident report on the avalanche that caught a snowmobiler on Kirkwood Ridge in the southern Madison Range on March 7th that is worth looking at: accident report, video.