Good morning. This is Eric Knoff with the Gallatin National Forest Avalanche Advisory issued on Sunday, February 13, at 7:30 a.m. Hans Saari Memorial Fund, in cooperation with the Friends of the Avalanche Center, sponsors today’s advisory. This advisory does not apply to operating ski areas.
The GNFAC would like to extend a huge thanks to all who participated in the King & Queen of the Ridge yesterday. The event was a great success. Congratulations to the King – Alex Lussier who tied the record with 29 hikes and the Queen Nikki Kimball who put in an amazing performance with 25 hikes.
Freight train winds have been the main weather event over the past 24 hours. Currently, winds are cranking out of the WSW at 30-40 mph with gusts reaching over 50 mph in most mountain locations. Temperatures are in the mid 20s to low 30s F and will rise into the 40s by this afternoon. Skies will be partly cloudy today and winds will gradually decrease by this evening.
The Bridger Range, The Madison and Gallatin Ranges, the Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range:
The old saying 'If you don't like the weather in Montana wait 5 minutes' seems to be more accurate than ever. Temperatures have fluctuated wildly; ranging from well below zero this past Wednesday to near fifty degrees above zero yesterday. The one common element that has tied the last few days together is WIND!
Strong winds and fresh snow have created ideal conditions for snow transport and wind loading. Yesterday, multiple natural avalanches were observed around Cooke City; all resulting from a heavy wind load. Although these slides were confined to the new snow and not propagating long distances, they were large in number.
The mountains around West Yellowstone have received less snow over the past week, but a widespread weak layer buried 10-12 inches below the surface will make wind loaded slopes sensitive to the weight of a skier or rider (photo).
The mountains around Bozeman and Big Sky also have a buried weak layer which is being stressed by recent wind loading. Yesterday, a snowmobiler triggered a small wind slab in the second Yellowmule off Buck Ridge (photo). This slide was not large in nature, but similar slides could have dire consequences if triggered in steeper more exposed terrain. Today, the primary avalanche concern is wind slabs that may be resting over a layer of small grained facets. This layer is not present on every slope, but is widespread enough to warrant a major heads up.
Today, the avalanche danger is rate CONSIDERABLE on all wind loaded slopes. Slopes that have not received a wind load have a MODERATE avalanche danger.
I 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.