Good Morning and happy St. Patrick’s Day. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Saturday, March 17th at 7:00 a.m. Today’s advisory is sponsored by Grizzly Outfitters in partnership with the Friends of the Avalanche Center. This advisory does not apply to operating ski areas.
Overnight the mountains near West Yellowstone picked up 1-2” of new snow while the rest of the advisory area remained dry. This morning temperatures are in the teens and winds are blowing 10-20 mph out of the S-SE. Today, skies will be partly to mostly cloudy and temps will warm into the 20’s to low 30’s. Winds will shift slightly and remain light to moderate out of the S-SW. The national weather service has lowered snow totals for the next storm system. By tomorrow morning the mountains near West Yellowstone will 4-6” while the rest of the advisory area will see 2-4”.
The snow that fell earlier this week was still sensitive yesterday, mainly in the Bridger Range. Alex skied north of Bridger Bowl and described conditions as “very reactive”. Storm slabs were breaking 10-12” deep, failing on a lower density layer of dendrites sitting over an ice crust (photo, photo). I don’t expect conditions to be quite as touchy today, but I would still approach all avalanche terrain with caution.
The new snow wasn’t as reactive in Beehive Basin yesterday, but my partner and I observed a few natural avalanches in wind loaded terrain (video). Today, all wind loaded slopes will remain suspect. Keep an eye out for recent wind loading near upper elevation ridgelines and watch for signs of instability such as cracking and collapsing. Avoiding wind loaded terrain and keeping slope angles less than 35 degrees will be a sure fire way to stay out of trouble.
Today, human triggered avalanches are possible and the avalanche danger is rated MODERATE.
The mountains around Cooke City and West Yellowstone don’t have the new snow instabilities that the northern ranges have. In general, the snowpack is mostly stable and the likelihood of triggering a slide is low (video, video). With that said, human triggered avalanches can’t be entirely ruled out. This means standard backcountry protocol applies, which entails: everyone carries proper rescue gear and knows how to us it, only one person at a time is exposed to avalanche terrain and always watch your partner from a safe location.
Although generally safe avalanche conditions exist this morning, the avalanche danger could increase by this afternoon if the next storm hits earlier and harder than expected. Keep an eye out for blowing and drifting snow and avoid steep terrain if instability is on the rise.
Today, human triggered avalanches are unlikely and the avalanche danger is rated LOW. The avalanche danger could rise to MODERATE by this afternoon with the addition of new and wind-blown snow.
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
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.
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.