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GNFAC Avalanche Advisory for Mon Feb 23, 2015
Snowpack and Avalanche Discussion
Bridger Range Northern Madison Range
Northern Gallatin Range
Eric Knoff on top of Palace Butte in Hyalite on a windless, cold, winter day. Perfect. Photo: GNFAC
This small slab was triggered by a skier near Mt Blackmore in the northern Gallatin Range on Sunday 2/22/15. Although small, this type of slide can be dangerous, especially if triggered in steep, high consequence terrain. Photo K. Lalli
This natural avalanche was observed near Mt Bole up Hyalite Canyon. This slide likley released during or immediately after the storm that dropped nearly 20" of new snow in the northern Gallatin Range. Photo GNFAC
Forecast link: GNFAC Avalanche Advisory for Mon Feb 23, 2015
GNFAC Avalanche Advisory for Sun Feb 22, 2015
Snowpack and Avalanche Discussion
Bridger Range Northern Madison Range
Northern Gallatin Range
Yesterday, skiers and riders were out in force taking advantage of the deepest snow the northern mountains have seen in weeks. Fortunately, the GNFAC did not receive any reports of natural or human triggered avalanches. This is a good indication the new snow has bonded well to the old snow surface in most locations.
GNFAC Avalanche Forecast for Sat Feb 21, 2015
Snowpack and Avalanche Discussion
Bridger Range Northern Madison Range
Northern Gallatin Range
In the last 48 hours, the Bridger Range and northern Gallatin Range received 1.0 and 1.3 inches of snow water equivalent respectively totaling over a foot of snow, and the mountains near Big Sky received 0.5 inches of snow water equivalent. Some places like Hyalite in the northern Gallatin Range could easily have 2 feet of new snow today.
"Triggered two small avalanches in wolverine bowl today. One started from sluff we kicked off while descending from the ramp into the bowl. The second was triggered by my friend on a 40 degree SE convex slope. The crown was no deeper then 1 ft, but it broke over 150ft wide. Not enough debris to be scary, but with another foot of snowfall I would worry. Both slides broke on a soft crust at the new/old interface." Photo: P. Dixon
GNFAC Avalanche Advisory for Fri Feb 20, 2015
Snowpack and Avalanche Discussion
Bridger Range Madison Range Gallatin Range
Lionhead Area near West Yellowstone Cooke City
This morning’s new snow should bond well to the old snow. The Bridger Range had similar snowfall amounts to Big Sky, but a much higher water content (0.6 inches of water compared to 0.2 inches). Fortunately the Bridger Range has a strong snowpack with no persistent weak layers (video).
If skiing or riding today I would do three things to assess stability: