Good morning. This is Mark Staples with the Gallatin National Forest Avalanche Advisory issued on Saturday, March 16 at 7:30 a.m. The Cold Smoke Awards in partnership with the Friends of the Avalanche Center sponsors today’s advisory. This advisory does not apply to operating ski areas.
This morning ridgetop temperatures were in the low 20s F. Lower elevations had temperatures in the high 20s F. Winds were blowing westerly at 10-15 mph in most areas. Today will be cooler than yesterday, and temperatures will be in the high 20s F to low 30s F with some sunshine and clouds. Winds will continue at 10-15 mph generally from the W. There is a chance for snow today and a better chance tonight. By tomorrow morning, 1-3 inches will accumulate in most areas. Snowfall will continue tomorrow.
Bridger Range Madison Range Gallatin Range
Lionhead area near West Yellowstone Cooke City
This time of year avalanche conditions can vary as much as the weather and change equally as fast. The good news is that temperatures dropped below freezing last night. These cold temperatures refroze the snow surface and will limit wet avalanches today but not eliminate this problem completely.
Yesterday, wet slab avalanches were observed on the west side of the Bridger Range (photo) and in a few places near Moonlight Basin and Big Sky. Smaller wet avalanches were observed including a few that Gallatin N.F. Snow Rangers intentionally triggered along a road in the northern Gallatin Range (video). At mid to low elevations in areas the snowpack became completely wet yesterday and only refroze at the surface this morning.
At higher elevations (roughly above 9K feet) the snowpack became wet in the surface layers only and refroze very well last night. These areas will have few avalanche concerns today; however, weak layers of faceted snow are still lurking in the snowpack. Eric found such a layer buried about 2 feet deep near Cooke City on a south aspect at 9600 feet.
Today, be wary of mid to low elevation slopes where the snowpack was completely wet yesterday. Avalanches remain possible on these slopes even if the surface is frozen because deeper layers of snow may remain wet and weak. At higher elevations with a deeper, stronger, and colder snowpack, look for buried faceted layers 2-3 feet deep and conduct a few quick stability tests. For today the overall avalanche danger is rated MODERATE.
Eric 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.