Good morning. This is Doug Chabot with the Gallatin National Forest Avalanche Advisory issued on Wednesday, March 30, at 7:30 a.m. Native Optics, in cooperation with the Friends of the Avalanche Center, sponsors today’s advisory. This advisory does not apply to operating ski areas.
A very moist system from the Pacific has begun dropping snow in the mountains. At 6 a.m. five to seven inches has fallen on a northwest flow. Winds started to increase out of the west yesterday afternoon and are averaging 20-25 mph with gusts of 35 mph. Mountain temperatures are in the high teens and will rise into the mid 20s as ridgetop winds shift to the northwest. This storm will continue into Thursday. By tomorrow morning I’m expecting 12+ inches of additional snow in the mountains.
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
Weather stations are reading a uniform five to seven inches over southwest Montana. The snow density is measuring 5-8% powder on most sites, which is a nice consistency to ski, but also light enough to be blown around. 20-30 mph winds are a perfect speed to load leeward slopes. With winds and snowfall continuing unabated today, I expect the likelihood of avalanches to rise steadily.
A large avalanche was noted on the east face of Sacagawea Peak in the Bridger Range yesterday. It looked as though a falling cornice may have triggered it, and likely broke during the storm Sunday night. Yesterday I toured north of Bridger Bowl and found good stability in my snowpit, although I noted a thin layer of facets breaking a foot deep under the new snow (snowpit). With today’s storm I expect avalanches to be breaking there as well. Given the rapid, steady loading, natural avalanche activity will increase. With poor visibility today, be extra careful traveling in avalanche terrain—both in the runout zones and also on the ridgelines where monstrous cornices are teetering and easily broken. Both spots are bad news today.
This morning the avalanche danger throughout our advisory area is currently rated CONSIDERABLE on all wind-loaded slopes and MODERATE elsewhere. I anticipate the avalanche danger to rise further as the storm continues. Another six inches of snowfall would push the danger to CONSIDERABLE on all slopes.
Mark will issue the next advisory tomorrow morning at 7:30 a.m. If you have any snowpack or avalanche observations, drop us a line at mtavalanche@gmail.com or call us at 587-6984.
Ride in honor of Steve Green
This Saturday, April 2nd, is a memorial ride on Buck Creek Ridge in honor of Steve Green who died in an avalanche last April in McAtee Basin. Meet at 9:30 a.m. at the Buck Creek parking lot near the Corral. Click HERE for more information.
Last Advisory
The last avalanche advisory of the winter is Sunday, April 10th. That will be our 145th advisory of the season—more than any other in our 21 year history.